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Coated abrasive 涂附磨具 An abrasive tool consisting of a flexible backing material, such as a woven cloth, paper or vulcanized fibre, a bond material, such as a glue or synthetic resin, and grit.
一种研磨工具,由柔性背衬材料(例如编织布、纸或硫化纤维)、粘合材料(例如胶水或合成树脂)和砂砾组成。
Countersinking 埋头孔 The flaring out of the rim of a drilled hole to form a truncated conical depression to receive a screw having a conical head, thus giving a flush fitting.
从钻孔的边缘向外张开以形成截锥形凹陷,以容纳具有锥形头的螺钉,从而提供齐平的配件。
Design code 设计规范 (design standard) A standard or specification for any aspect of engineering design, issued by national organizations such as ANSI, ASME, BSI, DIN, and ISO.
(设计标准)工程设计任何方面的标准或规范,由ANSI、ASME、BSI、DIN和ISO等国家组织发布。
X–Y recorder X-Y记录仪 A device that plots a graph of a variable y against a variable x, both in the form of voltages.
一种绘制变量y和变量x的图形的设备,两者都以伏特数的形式。
Thread insert 螺纹嵌件 (threaded bushing) Either a thin cylinder with an internal thread (and sometimes also an external thread) or a helical coil of wire, pressed or screwed into a hole to accept a bolt or screw. Used in material too soft or a component too thin to be threaded, to change one form of thread to another or to repair a damaged thread.
(螺纹衬套)一种带有内螺纹(有时也有外螺纹)的薄圆柱体或螺旋形线圈,压入或拧入孔中以接受螺栓或螺钉。用于材料太软或部件太薄而无法螺纹连接,用于将一种形式的螺纹更换为另一种形式或修复损坏的螺纹。
Complete decarburization 完全脱碳 Decarburization with sufficient carbon loss to show only clearly defined ferrite grains under metallographic examination.
脱碳,具有足够的碳损失,以在金相检查下仅显示清晰定义的铁素体晶粒。
Surface treatment 表面处理 Any process, including chemical, electrochemical, mechanical, and thermal, designed to protect a surface against corrosion and wear or to alter its mechanical properties.
任何旨在保护表面免受腐蚀和磨损或改变其机械性能的工艺,包括化学、电化学、机械和热处理。
Blind rivet 盲孔铆钉 A rivet that enables a connexion to be made from one side only of an assembly.
一种铆钉,可以仅从组件的一侧进行连接。
Free joint 万向节 The joint on a robot arm and wrist that causes the greatest end-effector movement when a specified force is applied to the end effector, i.e. that has the lowest stiffness with regard to the force.
机器人手臂和手腕上的关节,当指定的力施加到末端执行器时,会导致末端执行器的最大运动,即相对于力具有最低刚度。
Transgranular 穿晶 Through or across crystals or grains. Also known as intracrystalline or transcrystalline.
穿过或横穿晶体或颗粒。也称为晶内或晶间。
Cyaniding 氰化 A case-hardening process in which a ferrous material is heated above the lower transformation range in a molten salt containing cyanide to cause simultaneous absorption of carbon and nitrogen at the surface and, by diffusion, create a concentration gradient. Quench hardening completes the process.
一种表面硬化工艺,将含铁材料在含氰化物的熔融盐中加热至低于较低转变范围,使其表面同时吸收碳和氮,并通过扩散形成浓度梯度。淬火硬化完成该过程。
Cavitation tunnel 空泡试验筒 A closed-circuit recirculating water tunnel in which the static pressure can be reduced to sufficiently low levels for cavitation studies to be performed.
一种闭路循环水隧洞,其中静压可降至足够低的水平,以便进行气蚀研究。
Maximum continuous load 最大连续负载 (maximum continuous rating) (Unit kg/s) The maximum rate of steam output that a boiler can supply for a specified period, usually 24 hours.
(最大连续额定功率)(单位为kg/s)锅炉在规定时间内(通常为24小时)可供应的最大蒸汽输出率。
Rpm (N) 转速(N) An abbreviation for revolutions per minute. It is a widely used non-SI unit for rotational speed. The corresponding angular velocity ω in rad/s is given by πN/30. Rps (revolutions per second) is also used, the angular velocity then being 2πN.
每分钟转数的缩写。它是一种广泛使用的转速非SI单位。相应的角速度ω,单位为rad/s,由πN/30给出。还使用Rps(每秒转数),此时角速度为2πN。
Stress-intensity factor 应力强度因子 A scaling factor, usually denoted by the symbol K, used in linear-elastic fracture mechanics to describe the intensification of applied stress at the tip of a crack of known size and shape. At the onset of rapid crack propagation in any structure containing a crack, the factor is called the critical stress-intensity factor, or the fracture toughness.
一种标度因子,通常用符号K表示,在线弹性断裂力学中用于描述已知尺寸和形状的裂纹尖端施加应力的增强。在任何含有裂纹的结构中,裂纹快速扩展开始时,该因子称为临界应力强度因子,或断裂韧性。
Uniaxial strain 单轴应变 Increase (or decrease) in length resulting from a stress acting parallel to the longitudinal axis of the specimen.
由平行于试样纵轴的应力引起的长度增加(或减少)。
Ackerman linkage 阿克曼装置 A steering linkage on a motor vehicle that approximately gives rolling without slipping of both wheels about the turning point. This is achieved by having the inner stub axle (on the inside of the turning curve) move through a greater angle than the outer stub axle.
机动车辆上的一种转向联动装置,在转向点附近两个车轮几乎不会打滑。这是通过使内短轴(在转弯曲线的内侧)比外短轴移动更大的角度来实现的。
Compressive strength 抗压强度 Maximum compressive stress a material is capable of developing. With a brittle material that fails in compression by fracturing, the compressive strength has a definite value. For ductile, malleable, or semiviscous materials (which do not fail in compression by a shattering fracture), the value obtained for compressive strength is an arbitrary value dependent on the degree of distortion that is regarded as effective failure of the material.
材料能够产生的最大压缩应力。如果脆性材料因破裂而无法压缩,则抗压强度具有一定值。对于韧性、可锻性或半粘性材料(不会因破裂而导致压缩失效),获得的抗压强度值是一个任意值,取决于被视为材料有效失效的变形程度。
Toughness (Unit J/m²) 韧性(单位:J/m²) The ability of a metal to absorb energy and deform plastically before fracturing. 1. The ability of a material to resist crack initiation and propagation. 2. The ability of a material to absorb strain energy without fracturing.
金属在破裂前吸收能量和塑性变形的能力。1.材料抵抗裂纹萌生和扩展的能力。2.材料在不发生断裂的情况下吸收应变能的能力。
Cylinder head 气缸盖 The machined casting, typically of aluminium alloy or cast iron, that fits above the cylinder block of a piston engine and closes off the cylinders. It normally includes part of the combustion chambers and holes for the valves and spark plugs.
活塞式发动机缸体上方的机械铸件,通常由铝合金或铸铁制成,用于封闭气缸。它通常包括燃烧室的一部分以及阀门和火花塞的孔。
Imperial system of units 英制单位 British imperial system of units) An obsolete system of units first defined in the British Weights and Measures Act of 1824. Its three base units were second (time), yard (length), and pound avoirdupois (mass). The imperial unit of capacity was the gallon. The many associated units introduced subsequently include cubic inch, cubic foot, cubic yard, pint, and quart for both liquid and dry measures of capacity (i.e. volume); ounce, hundredweight, short and long ton for avoirdupois mass; poundal for force; minute and hour for time; fahrenheit for temperature; and British thermal unit for energy. Closely related to the imperial system of units is the US customary system of units. Each imperial unit is now legally defined in terms of the metric (i.e. SI) equivalent.
(英帝国单位制)1824年英国度量衡法首次定义的已被淘汰的单位制。其三个基本单位为秒(时间)、码(长度)和磅(质量)。容量的英制单位是加仑。随后引入的许多相关单位包括立方英寸、立方英尺、立方码、品脱和夸脱,用于液体和干燥容量测量(即体积);盎司,百分之一百重量,短吨和长吨,以保证重量;磅达表示力;以分钟和小时表示时间;华氏温度;英国热能单位。与帝国单位制密切相关的是美国习惯单位制。现在,每个英制单位在法律上都是以公制(即SI)当量来定义的。
Sample standard deviation (s) 样本标准偏差(s) The square root of the sample variance. It is a point estimate of the population standard deviation, a measure of the “spread”of the frequency distribution of a population. This value of sprovides a statistic that is used in computing interval estimates and several test statistics. For small sample sizes, s underestimates the population standard deviation.
样本方差的平方根。它是总体标准偏差的点估计,是总体频率分布“扩散”的度量。SPR的这个值提供了一个用于计算区间估计和若干测试统计量的统计量。对于小样本,s低估了总体标准偏差。
Ball mill 球磨机 A mill for grinding and pulverizing materials, consisting of a horizontal rotating drum containing loose steel or ceramic balls.
一种用于研磨和粉碎物料的磨机,由装有松散钢球或陶瓷球的水平旋转滚筒组成。
Accelerated testing 加速测试 A type of testing, for rates of wear, fatigue, corrosion etc., in which failure times are reduced by employing greater loads, more frequent power cycling, higher vibration levels, higher humidity, higher temperatures, greater potential differences etc. than would be encountered in normal operation.
一种测试类型,用于测试磨损率、疲劳率、腐蚀率等,通过采用比正常运行中更大的负载、更频繁的功率循环、更高的振动水平、更高湿度、更高温度、更大的电位差等,减少故障时间。
Cup washer 杯形垫圈 A dished leather or neoprene washer fitted to the rod end in some piston-style pumps.
在某些活塞式泵中,安装在杆端的碟形皮革或氯丁橡胶垫圈。
Continuous precipitation 连续沉淀 Precipitation from a supersaturated solid solution in which the precipitate particles grow by longrange diffusion without recrystallization of the matrix. Continuous precipitates grow from nuclei distributed more or less uniformly throughout the matrix. They usually are randomly oriented, but may form a Widmanstätten structure.
来自过饱和固溶体的沉淀,其中沉淀颗粒通过长程扩散生长而无需基质再结晶。连续析出物从在整个基体中或多或少均匀分布的核生长而来。它们通常是随机取向的,但可能形成魏氏结构。
Equation, short form 方程式,简写形式 An empirical equation which relates the torque applied to the bolt to the preload created in it, and which depends mainly on an experimentally derived factor called the Nut factor.
一个经验公式,将施加在螺栓上的扭矩与螺栓中产生的预载荷联系起来,主要取决于一个称为螺母系数的实验得出的系数。
Progressive aging 渐进时效 Aging by increasing the temperature in steps or continuously during the aging cycle.
通过在时效周期中逐步或连续升高温度进行增加时效。
Homogenizing 均质化 Holding at high temperature to eliminate or decrease chemical segregation by diffusion.
保持高温以消除或减少扩散引起的化学偏析。
Crest clearance (Unit m) 顶隙(单位米) For screw threads and gearing, the radial clearance between the crest of a thread (or gear) and the root of the engaging thread (or gear).
对于螺纹和齿轮,螺纹(或齿轮)的顶部与啮合螺纹(或齿轮)的根部之间的径向间隙。
Shore hardness 肖氏硬度 A measure of the hardness of materials such as elastomers, plastics, and rubbers determined using a Shore durometer which measures the penetration depth of a hardened steel rod (the indenter) 1.1–1.4 mm in diameter into the test material for a given force applied rapidly with a calibrated spring. There are two main indenter designs: type A (for softer materials) for which the end of the rod is a truncated 35° cone tapering to a diameter of 0.79 mm, and type D (harder materials) for which the end is a 30° cone with a 0.1 mm radius tip. The spring force is 8.05 N for type A and 44.45 N for type D. The hardness value is related to the penetration depth (limited to a maximum of 2.5 mm) such that for zero penetration the hardness is 100 and for maximum penetration the hardness is zero. The relevant standards are ISO 48-1, 48-4, and 48-7. Shore hardness values of selected materials are as follows: ABS 100, cellulose acetate 50–95, high-density polyethylene 60–70, low density polyethylene 40–50, polymethylmethacrylate 90–99, PTFE 50–65, and plasticized PVC 15–70.
使用肖氏硬度计测量弹性体、塑料和橡胶等材料的硬度,肖氏硬度仪测量直径为1.1–1.4mm的硬化钢棒(压头)在用校准弹簧快速施加的给定力下渗入试验材料的深度。有两种主要的压头设计:A型(适用于较软的材料),其杆端为截头35°锥形,逐渐变细至直径0.79 mm;D型(较硬的材料),端部为30°锥形,尖端半径为0.1mm。A型的弹簧力为8.05N,D型为44.45N。硬度值与渗透深度相关(最大限制为2.5mm),因此,对于零渗透,硬度为100,对于最大渗透,硬度是零。相关标准为ISO 48-1、48-4和48-7。所选材料的肖氏硬度值如下:ABS100、醋酸纤维素50-95、高密度聚乙烯60-70、低密度聚乙烯40-50、聚甲基丙烯酸甲酯90-99、PTFE50-65和塑化PVC15-70。
Cellular materials 蜂窝材料 There are three broad classes of materials that have a sponge-like structure containing many small closed or open (interlinked) pores or cells. Natural cellular materials include bone, cork, sponge, and wood, and have numerous well-known uses. Wide ranges of cellular plastics are produced using blowing or foaming agents, such as air, ammonium carbonate, sodium bicarbonate, etc., to create pores during the processing of thermoplastic or thermosetting polymers. Rigid foams have moderate compressive strength and can be moulded and machined.
有三大类材料具有海绵状结构,包含许多小的封闭或开放(互连)孔或细胞。天然多孔材料包括骨骼、软木、海绵和木材,有许多众所周知的用途。使用发泡剂或发泡剂(如空气、碳酸铵、碳酸氢钠等)生产各种泡沫塑料,以在热塑性或热固性聚合物加工过程中产生孔隙。硬质泡沫具有中等抗压强度,可模制和机加工。
Continuous-type furnace 连续式炉 A furnace used for heat treating materials that progress continuously through the furnace, entering one door and being discharged from another. See belt furnac, direct-fired tunnel-type furnac, rotary retort furnace, shaker-hearth furnace.
一种用于热处理材料的炉子,该炉子连续通过炉子,进入一个门并从另一个门排出。参见带式高炉、直燃隧道式高炉、旋转罐式炉、振动炉。
Columnar structure 柱状结构 A coarse structure of parallel elongated grains formed by unidirectional growth, most often observed in castings, but sometimes in structures resulting from diffusional growth accompanied by a solid-state transformation.
由单向生长形成的平行细长晶粒的粗略结构,最常见于铸件中,但有时也出现在伴随固态转变的扩散生长产生的结构中。
Contact strength (Unit N) 接触强度(单位N) The maximum allowable load between contacting bodies converted into a stress.
换算成应力的接触体之间的最大允许载荷。
Black annealing 黑退火 Box annealing or pot annealing ferrous alloy sheet, strip, wire to impart a black color to the oxidized surface.
对铁合金板、带、线进行箱式退火或罐式退火,使氧化表面呈黑色。
Transmission 传输 The system that transmits power and torque from a power source; for example a shaft, belts and pulleys, or a gear train. In the case of a motor vehicle, it includes the gearbox, clutch, propeller shaft, differential and final drive shafts.
从动力源传输功率和扭矩的系统;例如轴、皮带和滑轮或齿轮系。对于机动车辆,包括变速箱、离合器、传动轴、差速器和终传动轴。
Microindentation hardness test 显微压痕硬度测试 Hardness test using a calibrated machine to force a diamond indenter of specific geometry, under a test load of 1 to 1000 gramforce, into the surface of the test material and to measure the diagonal or diagonals of the indentation optically.
使用校准机器进行硬度试验,以在1至1000克力的试验载荷下,将特定几何形状的金刚石压头压入试验材料表面,并光学测量压痕的对角线。
Heat-treatable alloy 可热处理合金 An alloy that can be hardened by heat treatment.
一种可以通过热处理硬化的合金。
Vapour–pressure curve 蒸汽压力曲线 For a pure substance, the curve of saturation pressure plotted vs saturation temperature.
对于纯物质,绘制了饱和压力与饱和温度的曲线。
Fretting fatigue 微动疲劳 Fatigue fracture that initiate at a surface area where fretting has occurred. The progressive damage to a solid surface that arises from fretting.
在发生微动的表面区域开始的疲劳断裂。由微动引起的对固体表面的渐进性损坏。
Generator 发电机 1. A machine for converting mechanical energy to electrical energy. 2. (generatrix) A point, line, or surface regarded as moving and so forming a line, a surface, or a volume, respectively.
1.将机械能转化为电能的机器。2.(母线)被认为是运动的点、线或面,因此分别形成一条线、一个面或一个体积。
Dimensioning 尺寸标注 The specification on an engineering drawing of the size (e.g. length, radius, angle, or spacing) and the relative location (e.g. angular position) of each feature of a component. The numerical values often include the tolerances. There should be no more dimensions than are necessary to manufacture the component.
工程图纸上对部件每个特征的尺寸(例如长度、半径、角度或间距)和相对位置(例如角位置)的规范。数值通常包括公差。尺寸不应超过制造组件所需的尺寸。
Dynamics 动力学 The branch of mechanics that deals with objects in motion. Its two main branches are kinematics, which studies motion without regards to its cause, and kinetics, which also takes into account forces that cause motion.
力学中研究运动物体的分支。它的两个主要分支是运动学和动力学,前者研究运动而不考虑其原因,后者也考虑引起运动的力。
Nanomanufacturing 纳米制造 1. The manufacture of nanoscale materials. 2. The manufacture of components or devices that have critical dimensions of order 1 nm.
1.纳米材料的制造。2.具有1nm级临界尺寸的部件或装置的制造。
Eutectoid 共析 (1) An isothermal reversible reaction in which a solid solution is converted into two or more intimately mixed solids on cooling, the number of solids formed being the same as the number of components in the system. (2) An alloy having the composition indicated by the eutectoid point on an equilibrium diagram. (3) An alloy structure of intermixed solid constituents formed by a eutectoid reaction.
(1)一种等温可逆反应,其中固溶体在冷却时转化为两种或两种以上紧密混合的固体,形成的固体数量与系统中组分的数量相同。(2)具有平衡图上共析点所示成分的合金。(3)由共析反应形成的混合固体成分的合金结构。
Acoustic pyrometer 声学高温计 A non-intrusive pyrometer based on the principle that the sound speed in a gas is proportional to the square root of its absolute temperature.
一种非侵入式高温计,其原理是气体中的声速与其绝对温度的平方根成正比。
Strength of bolt 螺栓强度 An ambiguous term which can mean Ultimate strength or Proof load or Endurance limit or Yield strength.
一个模棱两可的术语,可表示极限强度或验证荷载或耐久极限或屈服强度。
Pressure storage tank 压力贮存器 (pressure vessel) A closed container for storing gases or volatile liquids, such as liquefied gases, at pressures significantly above atmospheric pressure. Such tanks are commonly cylindrical with domed ends, spherical, spheroidal, torispherical or hemispherical.
(压力容器)密闭容器:在大气压以上的压力下储存气体或挥发性液体,如液化气体的密闭容器。此类贮存器通常为圆柱形,具有半球形端部、球形、球面或半球形。
International Bureau of Weights and Measures 国际度量衡局IBWM (BIPM, Bureau International des Poids et Mesures) The intergovernmental organization which has the mandate to provide the basis for a single, coherent system of measurements, traceable to the International System of Units.
(BIPM,国际计量局)政府间组织,其任务是为可追溯到国际单位制的单一、一致的计量系统提供基础。
Thread milling 螺纹铣削 Thread milling is a method of cutting screw threads with a milling cutter in a thread mill. Thread milling cutters are either single form or multiple form and are used in either conventional or planetary thread mills.
螺纹铣削是在螺纹铣刀中用铣刀切削螺纹的一种方法。螺纹铣刀为单形或多形,用于传统或行星式螺纹铣刀。
Stress cycles endured (N) 承受的应力循环(N) The number of cycles of a specified character (that produce fluctuating stress and strain) that a specimen has endured at any time in its stress history.
试样在其应力历史中任何时间所经受的特定特征(产生波动应力和应变)的循环次数。
Weld penetration 焊接熔深 It is the depth below the surfaces, as revealed in microstructural sections of joined metals, which is melted during welding.
它是焊接过程中熔化的连接金属的微观结构截面所显示的表面以下的深度。
Hot working 热加工 Plastic deformation of a metal, by rolling, drawing, forging, etc., at a temperature above its recrystallization temperature (in commercial alloys above about 40% of their melting points in kelvins) which results in permanent shape change but no increase in strength or loss of ductility.
金属通过轧制、拉拔、锻造等在高于其再结晶温度(在商业合金中高于其熔点的40%的开尔文)的温度下发生塑性变形,导致永久的形状变化,但不会增加强度或失去延展性。
Positive-displacement compressor 容积式压缩机 Any type of compressor, including piston and rotary-screw types, that delivers a fixed volume of gas at high pressure per unit time. A positive-displacement pump delivers a fixed volume of fluid, usually a liquid, per unit time.
任何类型的压缩机,包括活塞式和旋转螺杆式,在单位时间内以高压输送固定体积的气体。容积泵每单位时间输送固定体积的流体,通常为液体。
Nut box mechanism 螺母箱机械装置 In a lathe it is used to engage and disengage the lead screw for thread cutting. This comprises a pair of half-nuts capable of sliding in vertical slides in or out of mesh with the lead screw.
在车床中,它用于接合和分离丝杠以进行螺纹切削。这包括一对半螺母,能够在与丝杠啮合的垂直滑动中滑动。
Transmission dynamometer 传动测功机 A dynamometer in which the power transmitted by a shaft is obtained from the product of its rotation speed and the torque determined from measured shear strains along the shaft.
一种测功机,其中轴传递的功率由其转速和扭矩的乘积获得,扭矩由沿轴测得的剪切应变确定。
Quimby screw pump 昆比螺杆泵 A screw pump with two meshing screws, each having a righthand and a left-hand screw. Liquid enters at either end and is discharged from the middle.
带有两个啮合螺钉的螺杆泵,每个都有一个右旋螺纹和一个左旋螺纹。液体从两端进入,从中间排出。
Fatigue crack growth rate (da/dN) 疲劳裂纹扩展率(da/dN) The rate of crack extension caused by constant-amplitude fatigue loading, expressed in terms of crack extension per cycle of load application.
恒幅疲劳荷载引起的裂纹扩展速率,以每次荷载施加循环的裂纹扩展表示。
Lock-nut pipe thread 锁紧螺母管螺纹 The lock-nut pipe thread is a straight thread of the largest diameter which can be cut on a pipe. Its form is identical with that of the American or Briggs standard taper pipe thread. In general, “Go” gages only are required. These consist of a straight-threaded plug representing the minimum female lock-nut thread, and a straight-threaded ring representing the maximum male lock-nut thread. This thread is used only to hold parts together, or to retain a collar on the pipe. It is never used where a tight threaded joint is required.
锁紧螺母管螺纹是最大直径的直螺纹,可在管道上切割。其形式与美国或布里格斯标准锥管螺纹相同。一般情况下,只需要通规。它们由一个表示最小内螺纹锁紧螺母螺纹的直螺纹塞和一个表示最大外螺纹锁紧螺帽螺纹的直形螺纹环组成。该螺纹仅用于将零件固定在一起,或用于将轴环固定在管道上。切勿使用于需要紧密螺纹接头的情况下。
Bend test 弯曲试验 A test for determining the relative ductility of metal that is to be formed (usually sheet, strip, plate, or wire) or for determining soundness and toughness of metal (after welding, for example). The specimen is usually repeatedly bent over a specified diameter through a specified angle and then unbent for a specified number of cycles. There are four general types of bend tests, named according to the manner in which the forces are applied to the specimen to make the bend: free bend, guided bend, semiguided bend, and wrap-around bend.
确定待成形金属(通常为薄板、带材、板材或线材)的相对延展性或确定金属的坚固性和韧性(例如,焊接后)的试验。试样通常在规定的直径上重复弯曲一个规定的角度,然后在规定的循环次数内弯曲。弯曲试验有四种一般类型,根据施加在试样上的力进行弯曲的方式命名:自由弯曲、引导弯曲、半引导弯曲和环绕弯曲。
Diffusion coefficient 扩散系数 A factor of proportionality representing the amount of substance diffusing across a unit area through a unit concentration gradient in unit time.
一个比例因子,表示在单位时间内通过单位浓度梯度扩散到单位面积上的物质量。
Volumetric efficiency 容积效率 For a piston engine, the ratio of the volume of the induced charge per induction stroke, determined at a reference pressure and temperature, to the swept volume.
对于活塞式发动机,在参考压力和温度下确定的每个进气冲程的进气体积与扫掠体积之比。
Stress distribution 应力分布 The manner in which tensile, compressive, and shear stresses are distributed within a loaded body, indicated by loci of constant stress.
拉应力、压应力和剪应力在受载物体内的分布方式,由恒定应力轨迹表示。
Condenser vacuum 冷凝器真空 The sub-atmospheric pressure imposed on the condenser of a steam-power plant which leads to an appreciable increase in overall efficiency.
施加在蒸汽发电厂冷凝器上的低于大气压的压力导致整体效率显着提高。
Magnetic materials 磁性材料 Materials in which the magnetic moment of adjacent atoms can adopt either parallel or antiparallel alignment. Ferromagnetism occurs when the magnetic moments adopt parallel alignment. When adjacent magnetic moments cancel due to antiparallel alignment, the material exhibits antiferromagnetism and has no overall magnetic moment. Examples of the latter include ferrous oxide and manganese oxide. The phenomenon of ferrimagnetism occurs when adjacent magnetic moments adopt antiparallel alignment but have unequal magnitude. The region of ferromagnetic or ferrimagnetic material in which the magnetic moments are aligned is known as a magnetic domain and adjacent regions are separated by domain walls. Diamagnetic and paramagnetic materials exhibit weak forms of magnetism that results from independent (uncoupled) alignment of magnetic atomic dipoles induced by an applied magnetic field. Ferromagnetic and ferrimagnetic materials can acquire high degrees of magnetization in relatively weak magnetic fields. They have different hysteresis characteristics and are classified as either hard magnets or soft magnets. Hard magnets retain large magnetization in the absence of an applied magnetic field and are used as permanent magnets. Conventional materials include magnet steels alloyed with tungsten or cobalt. Rare-earth magnets made from alloys of rare-earth elements produce significantly stronger magnetic fields. The most common of these are samarium-cobalt and neodymiumiron-boron permanent magnets. Their strength allows them to be small and used in numerous applications, including cordless tools, disk drives, headphones, toys, and motors for automotive components such as wipers, fans, washers, and windows. Soft magnets may be magnetized and demagnetized relatively easily. When subjected to an alternating magnetic  field the energy loss due to hysteresis is small. Common materials include iron-silicon alloys (known as electrical steels), nickel-iron alloys (permalloy), soft ferrites, and amorphous nanocrystalline alloys, the last of which can be produced in the form of tape by meltspinning. Soft magnets are used to enhance the magnetic flux produced by an electric current.
相邻原子的磁矩可以采用平行或反平行排列的材料。当磁矩采用平行排列时,会产生铁磁性。当相邻磁矩因反平行排列而抵消时,材料表现出反铁磁性,没有总磁矩。后者的实例包括氧化亚铁和氧化锰。当相邻磁矩采用反平行排列但大小不等时,就会出现铁磁现象。磁矩对齐的铁磁或铁磁材料区域称为磁畴,相邻区域由磁畴壁分隔。抗磁和顺磁材料表现出弱磁性形式,这是由外加磁场诱导的磁原子偶极子的独立(非耦合)排列引起的。铁磁性和铁磁性材料可以在相对弱的磁场中获得高磁化度。它们具有不同的磁滞特性,分为硬磁铁和软磁铁。硬磁铁在没有外加磁场的情况下保持较大的磁化强度,用作永磁体。常规材料包括与钨或钴合金化的磁钢。由稀土元素合金制成的稀土磁体产生明显更强的磁场。其中最常见的是钐钴和钕硼永磁体。它们的强度使其体积小,可用于多种应用,包括无绳工具、磁盘驱动器、耳机、玩具和汽车部件(如雨刷、风扇、洗衣机和车窗)的电机。软磁体可以相对容易地磁化和退磁。当受到交变磁场时,由于磁滞引起的能量损失很小。常见材料包括铁硅合金(称为电工钢)、镍铁合金(坡莫合金)、软铁氧体和非晶纳米晶合金,最后一种可以通过熔钉以胶带的形式生产。软磁铁用于增强电流产生的磁通量。
Heat balance (heat budget) 热平衡(热预算) An energy balance involving only heat transfer across the system boundary and the stored energy.
仅涉及跨系统边界的热传递和存储能量的能量平衡。
Shell hardening 壳型硬化 A surface-hardening process in which a suitable steel workpiece, when heated through and quench hardened, develops a martensitic layer or shell that closely follows the contour of the piece and surrounds a core of essentially pearlitic transformation product. This result is accomplished by a proper balance among section size, steel hardenability, and severity of quench.
一种表面硬化工艺,在该工艺中,合适的钢工件在加热和淬火硬化后,会形成一层马氏体层或壳,该层或壳紧随工件的轮廓,并包围一个基本上为珠光体相变产物的核心。这一结果通过截面尺寸、钢淬透性和淬火强度之间的适当平衡来实现。
Superheating 过热 Heating above the temperature at which an equilibrium phase transformation should occur without actually obtaining the transformation.
在不实际获得相变的情况下,加热到应发生平衡相变的温度以上。
Corrosion failure 腐蚀失效 1. The failure of a component or structure after corrosion has reduced the load-bearing area to an unsupportable level. 2. A situation in which a mechanism cannot function owing to corrosion products preventing free movement at joints.
1、部件或结构在腐蚀后失效,使承重面积减少到无法支撑的程度。2.由于腐蚀产物阻止关节处的自由运动,导致机构无法运行的情况。
Controlled cooling 控制冷却 Cooling from an elevated temperature in a predetermined manner, to avoid hardening, cracking, or internal damage, or to produce desired microstructure or mechanical properties.
以预定方式从升高的温度冷却,以避免硬化、开裂或内部损坏,或产生所需的微观结构或机械性能。
Range of stress (Sr) 应力范围(Sr) The algebraic difference between the maximum and minimum stress in one cycle—that is, Sr = Smax – Smin
一个循环中最大和最小应力之间的代数差,即Sr=Smax–Smin
Distortion 扭曲 Any deviation from an original size, shape, or contour that occurs because of the application of stress or the release of residual stress.
由于施加应力或释放残余应力而发生的与原始尺寸、形状或轮廓的任何偏差。
Thermodynamic state 热力学状态 The condition of a system or working fluid according to its properties.
系统或工作流体根据其性质的状态。
Wind tunnel 风洞 A duct in which a controlled flow of air is used for testing and research. Types include blow down, closed circuit, open return, and open section. Closed-circuit tunnels may be pressurized or evacuated. The working section is usually situated immediately downstream of the flow-conditioning elements, which may include a plenum chamber, honeycomb, screens, turbulence grids, and a contraction. Immediately downstream there is usually a diffuser. For basic research the usual requirement is for uniform steady flow in the working section with low swirl and turbulence intensity. For some applications the flow may be density stratified, sheared, unsteady, or of high turbulence intensity.
用于测试和研究的可控气流管道。类型包括排污、闭路、开路回路和开路段。闭路隧道可加压或排空。工作段通常位于流量调节元件的下游,可包括增压室、蜂窝、滤网、湍流格栅和收缩管。紧靠下游通常有一个扩散器。对于基础研究,通常的要求是在低涡流和湍流强度的工作段中实现均匀稳定流动。对于某些应用,流动可能是密度分层、剪切、不稳定或高湍流强度。
Uniform elongation 均匀伸长 The elongation at maximum load and immediately preceding the onset of necking in a tension test.
在拉伸试验中,在最大载荷下和颈缩开始之前的伸长率。
Load ratio, R 负载比R In fatigue, the algebraic ratio of the minimum to maximum load in a fatigue cycle, that is, R = Pmin/Pmax. Also known as stress ratio.
在疲劳中,疲劳循环中最小载荷与最大载荷的代数比,即 R= Pmin/Pmax。也称为应力比。
A-basis A-基础 Mechanical property value above which at least 99% of the population of values is expected to fall, with a confidence of 95%. Also called A-allowable.
机械性能值超过该值时,至少99%的值预计会下降,置信度为95%。也被称为A-容许。
Bulk velocity 体积速度 (average velocity, V) (Unit m/s) For fluid flow in a pipe or duct, the average flow velocity, given by V = ṁ/ρA where ṁ is the mass flow rate, ρ is the fluid density, and A is the duct cross-sectional area.
(平均速度,V)(单位m/s)对于管道或管道中的流体流动,平均流速,由V=ṁ/ρA给出,其中ṁ是质量流量,ρ是流体密度,A是管道截面积。
Total head (hT) (Unit m) 总水头(hT)(单位:m) Total pressure pT expressed in terms of the vertical height of a column of liquid, typically water or mercury, i.e. hT = pT/ρg where g is the acceleration due to gravity and ρ is the liquid density.
总压力pT以液体柱(通常为水或汞)的垂直高度表示,即hT=pT/ρg,其中g为重力加速度,ρ为液体密度。
Air cleaner 空气净化器 A device, such as a filter, hydrocyclone, or electrostatic precipitator, that removes particles and aerosols from a flow of air.
一种设备,例如过滤器、水力旋流器或静电除尘器,用于从气流中去除颗粒和气溶胶。
Carburizing flame 渗碳火焰 A gas flame that will introduce carbon into some heated metals, as during a gas welding operation. A carburizing flame is a reducing flame, but a reducing flame is not necessarily a carburizing flame.
一种气体火焰,会在气焊操作中将碳引入一些加热的金属中。渗碳火焰是还原火焰,但还原火焰不一定是渗碳火焰。
Zero time 零时 The time when the given loading or constraint conditions are initially obtained in creep or stressrelaxation tests, respectively.
分别在蠕变或应力松弛试验中初始获得给定载荷或约束条件的时间。
Electrode 电极 The two metallic bodies in a battery or Corrosion cell which give up electrons (the Anode) or which attract them (the Cathode).
电池或腐蚀电池中释放电子(阳极)或吸引电子(阴极)的两个金属体。
Radial wave equation 径向波动方程 A differential equation describing the transmission of a wave in a system with radial symmetry.
描述波在径向对称系统中传输的微分方程。
Critical compression ratio 临界压缩比 1. The compression ratio for incipient knock of hydrocarbon fuels as determined in a variable-compression single-cylinder piston engine. 2. The compression ratio at which an air–fuel mixture will spontaneously ignite due to the temperature increase produced.
1.在可变压缩单缸活塞发动机中确定的烃类燃料初期爆震的压缩比。2.空气-燃料混合物由于产生的温度升高而自燃的压缩比。
Barrier protection 屏障保护 The coating on a fastener is said to provide barrier protection if it merely isolates the fastener from the environment. Paint, for example, provides barrier protection.
如果仅将紧固件与环境隔离,则据说紧固件上的涂层可提供屏障保护。例如,油漆提供屏障保护。
Graham’s laws 格雷厄姆定律 The laws stating that the rates of diffusion and effusion of a gas are inversely proportional to the square root of its density.
规定气体的扩散和渗出速率与其密度的平方根成反比的定律。
Stainless steels 不锈钢 Iron-base alloys that are highly resistant to corrosion in many environments. The predominant alloying element is chromium, which, like iron at room temperature, has BCC crystal structure. Corrosion resistance by passivation is achieved by the formation of chromium oxide on the steel surface. Nickel, which has FCC crystal structure, is another important addition for some steels. Other additions used to enhance properties include manganese, molybdenum, niobium, and titanium. There are several classes of stainless steel.
在许多环境中具有高度耐腐蚀性的铁基合金。主要的合金元素是铬,与室温下的铁一样,铬具有BCC晶体结构。钝化抗腐蚀性是通过在钢表面形成氧化铬来实现的。具有FCC晶体结构的镍是某些钢的另一种重要添加剂。其他用于增强性能的添加剂包括锰、钼、铌和钛。不锈钢的种类有好几种。
GGas turbine G燃气轮机 An engine in which air, compressed by a multi-stage axial compressor and/or one or more centrifugal compressors, flows into a combustion chamber (or chambers) where fuel is burned and the hot gases then drive an axial turbine which powers the compressor.
由多级轴流压缩机和/或一个或多个离心压缩机压缩的空气流入燃烧室(或多个燃烧室),在燃烧室中燃烧燃料,然后热气体驱动轴流涡轮,为压缩机提供动力。
Profile 轮廓 The shape of a cross section of an object, such as an aerofoil or cam.
物体的横截面形状,如机翼或凸轮。
Amontons friction 阿蒙顿摩擦 (Coulomb friction) Friction between surfaces where the ratio of the frictional force F to the normal force N is constant and independent of the area in contact.
(库仑摩擦)摩擦力F与法向力N之比恒定且与接触面积无关的表面之间的摩擦。
Bioenergy 生物能源 1. Energy derived from materials such as purpose-grown energy crops, including sugar cane, maize, wheat, and rice, as well as wood, straw, and animal waste, including sewage, manure, and animal litter. 2. A term sometimes used to cover biomass and biofuels together.
1.来自特定种植的能源作物(包括甘蔗、玉米、小麦和大米)以及木材、稻草和动物粪便(包括污水、粪便和动物垃圾)等材料的能源。2.有时用于同时涵盖生物质和生物燃料的术语。
Elastic recovery 弹性恢复 Amount the dimension of a stressed elastic material returns to its original (unstressed) dimension on release of an applied load. In hardness testing, the shortening of the original dimensions of the indentation upon release of the applied load.
在释放施加的载荷时,受应力弹性材料的尺寸恢复到其原始(无应力)尺寸的量。在硬度测试中,当释放所施加的载荷时,压痕的原始尺寸缩短。
Vacuum relief valve 真空安全阀 A valve that admits gas to a system under vacuum, should the degree of vacuum become excessive.
如果真空度过高,允许气体在真空下进入系统的阀门。
High strength low alloy steels 高强度低合金钢 (HSLA steels) Steels with various micro-alloying elements such as copper, nickel, chromium, molybdenum, niobium, titanium, and vanadium in small quantities that give improved strength (as high as 900 MPa) and corrosion properties compared with plain carbon steels. Improvements are due to grain refinement and precipitation hardening, better control of the chemistry during steel making, and accurate rolling temperatures.
(HSLA钢)是含有各种微合金元素的钢,如少量的铜、镍、铬、钼、铌、钛和钒,与普通碳钢相比,具有更好的强度(高达900MPa)和腐蚀性能。这些改进归功于晶粒细化和沉淀硬化、炼钢过程中更好的化学控制以及精确的轧制温度。
Torque control 扭矩控制 A system of optimizing rotor speed for a variable-speed wind turbine by controlling the torque demands of the generator.
通过控制发电机的扭矩需求来优化变速风力涡轮机的转子速度的系统。
Crack size (a) 裂纹尺寸(a) A lineal measure of a principal planar dimension of a crack. This measure is commonly used in the calculation of quantities descriptive of the stress and displacement fields. In practice, the value of crack size is obtained from procedures for measurement of physical crack size, original crack size, or effective crack size, as appropriate to the situation under consideration.
裂纹主平面尺寸的线性度量。这种测量通常用于计算描述应力场和位移场的量。在实践中,裂纹尺寸的值是通过测量物理裂纹尺寸、原始裂纹尺寸或有效裂纹尺寸的程序获得的,视情况而定。
Bimetallic strip 双金属片 A strip formed by welding, riveting or brazing together two metals having different coefficients of expansion, which causes the strip to curl when its temperature changes. Typical combinations are steel and copper or steel and brass.
将两种膨胀系数不同的金属焊接、铆接或钎焊在一起形成的带材,当温度变化时,带材会卷曲。典型的组合是钢和铜或钢和黄铜。
Velocity ratio 速度比 1. The ratio between the input velocity to a machine, train of gears, etc. and the output velocity. 2. The ratio between the displacement of an applied force at one part of a mechanism and the movement of the load at a different part.
1.机器、齿轮系等的输入速度与输出速度之间的比率。2.在机构的一个部分处施加的力的位移与在不同部分处的载荷的移动之间的比率。
Hot dipping 热浸 (hot-dip galvanizing) A process of coating an iron, steel, or aluminium object with a thin layer of zinc by passing it through a bath of molten zinc at a temperature of about 460°C.
(热浸镀锌)通过使铁、钢或铝物体通过温度约为460°C的熔融锌浴,在铁、钢或铝物体上镀上一层薄薄的锌层的工艺。
Impact strength 冲击强度 The resiliency or toughness of a solid as measured by impact energy.
用冲击能量测量的固体的弹性或韧性。
Coextrusion 复合挤压 The simultaneous extrusion through the same die of two or more materials in combination.
通过同一模具同时挤出两种或多种材料的组合。
Materials selection 材料选择 The process of selecting the most suitable material for a particular application. In the case of solid materials, it involves assessment of candidate materials in terms of their physical properties (density, elastic moduli, fracture toughness, yield strength, hardness, fatigue resistance, coefficient of thermal expansion, thermal conductivity, resistance to thermal shock, creep resistance, corrosion resistance, radiation resistance, etc), and such factors as the function of the final product, its shape, method of manufacture, required tolerances, number to be made, ease of inspection and quality control, cost, and design methodology employed.
为特定应用选择最合适材料的过程。对于固体材料,它涉及根据其物理特性(密度、弹性模量、断裂韧性、屈服强度、硬度、抗疲劳性、热膨胀系数、导热系数、抗热冲击性、抗蠕变性、耐腐蚀性、抗辐射性等)评估候选材料,以及诸如最终产品的功能、其形状、制造方法、所需公差、制造数量、检查和质量控制的容易程度、成本和采用的设计方法等因素。
Coefficient of friction (μ) 摩擦系数(μ)  (coefficient of kinetic friction, coefficient of sliding friction, friction coefficient, μ) The ratio of the frictional force F to the normal force N between two surfaces in contact, i.e. μ = F/N. Static friction is when there is no relative sliding; kinetic friction when there is. For structural components sliding on one another, the coefficient of friction is the ratio of the force causing the sliding to the force perpendicular to the sliding component surfaces. The coefficient of friction is dimensionless with values between zero and one. The number characterising the force necessary to slide or roll one material along the€surface of another. If an object has a weight N and the coefficient of friction is μ, then the force F necessary to move it without acceleration along a level surface is F = μN. The coefficient of static friction determines the force necessary to initiate movement; the coefficient of kinetic friction determines the force necessary to maintain movement. Kinetic friction is usually smaller than static friction.
(动摩擦系数、滑动摩擦系数、摩擦系数,μ)两个接触表面之间摩擦力F与法向力N的比值,即μ=F/N。静摩擦是指没有相对滑动时;有摩擦时的动摩擦。对于相互滑动的结构部件,摩擦系数是引起滑动的力与垂直于滑动部件表面的力的比值。摩擦系数是无量纲的,其值介于0和1之间。代表一种材料沿另一种材料的表面滑动或滚动所需的力的数字。如果一个物体的重量为N并且摩擦系数为μ,那么在没有加速度的情况下沿水平表面移动它所需的力F为F=μN。静摩擦系数决定了启动运动所需的力;动摩擦系数决定了保持运动所需的力。动摩擦通常小于静摩擦。两个物体之间的力(F)与将这些物体压在一起的法向力(N)的无量纲比:μ(或f)=(F/N)。
Twist 扭转 The helix produced in a cylindrical component, such as a shaft, wire, tensioned cable, or rope, when one end is rotated relative to the other. Measured either as the number of turns per unit length, or by the helix angle (twist angle).
当一端相对于另一端旋转时,在圆柱形部件(如轴、钢丝、张紧电缆或绳索)中产生的螺旋。以每单位长度的圈数或螺旋角(扭曲角)测量。
Effective crack size (ae) 有效裂纹尺寸(ae) The physical crack size augmented for the effects of cracking plastic deformation. Sometimes the effective crack size is calculated from a measured value of a physical crack size plus a calculated value of a plastic-zone adjustment. A preferred method for calculation of effective crack size compares compliance from the secant of a load-deflection trace with the elastic compliance from a calibration for the type of specimen.
由于裂纹塑性变形的影响,物理裂纹尺寸增大。有时,根据物理裂纹尺寸的测量值加上塑性区调整的计算值来计算有效裂纹尺寸。计算有效裂纹尺寸的首选方法是将载荷-挠度轨迹正割的柔度与试样类型校准的弹性柔度进行比较。
Shear 扭剪 The type of force that causes or tends to cause two contiguous parts of the same body to slide relative to each other in a direction parallel to their plane of contact.
导致或倾向于导致同一物体的两个相邻部分在平行于其接触面的方向上相对滑动的力的类型。
Profilometer 轮廓仪 An instrument used to quantify the roughness of a surface. For a contact profilometer, a diamond stylus sweeps across the surface along a series of parallel lines. Noncontact profilometers use optical techniques to map the surface irregularities.
用于量化表面粗糙度的仪器。对于接触式轮廓仪,钻石触针沿一系列平行线扫过表面。非接触式轮廓仪使用光学技术绘制表面不规则。
Martensitic stainless steels 马氏体不锈钢 Martensitic stainless steels are hardenable magnetic stainless steels that contain 9–18% chromium, 0.06–1.25% carbon, and typically up to about 2.5% in total of manganese, silicon, nickel, and molybdenum. They can be heat-treated such that martensite is the prime microconstituent, and are usually available in the annealed or quenched-and-tempered condition. They have excellent strength and high hardness, and good corrosion resistance. Uses include cutlery, surgical instruments, rifle barrels, steam turbine tubing and blading, jet engine components, hand tools, machine parts, fasteners, valves, springs, bearings, pump shafts, nozzles, mining equipment, and wear-resistant parts.
马氏体不锈钢是一种可硬化的磁性不锈钢,其铬含量为9-18%,碳含量为0.06-1.25%,锰、硅、镍和钼的总含量通常高达约2.5%。它们可以进行热处理,使马氏体成为主要的微组分,通常可在退火或淬火回火条件下获得。它们具有优异的强度和高硬度,以及良好的耐腐蚀性。用途包括餐具、外科器械、步枪枪管、蒸汽轮机管道和叶片、喷气发动机部件、手动工具、机械零件、紧固件、阀门、弹簧、轴承、泵轴、喷嘴、采矿设备和耐磨零件。
Thermal fatigue 热疲劳 Fatigue resulting from the presence of temperature gradients that vary with time in such a manner as to produce cyclic stresses in a structure.
由于温度梯度的存在而产生的疲劳,温度梯度随时间变化,从而在结构中产生循环应力。
Composite property 复合属性 In thermodynamics, a property defined in terms of the properties of a closed system and its surroundings, such as the non-flow exergy function.
在热力学中,根据封闭系统及其周围环境的性质定义的性质,例如非流动火用函数。
Cavitation 空蚀空化 The formation of vapour- or gas-filled cavities in a liquid due to reduction of the local pressure, often due to acceleration of the fluid, such as in flow through a convergent nozzle. If there is no dissolved gas in the liquid, vaporous cavitation occurs when the pressure falls below the saturated vapour pressure. If the bubbles are formed due to high temperature, the process is termed boiling. If there is dissolved gas, gaseous cavitation occurs due to pressure reduction, temperature increase, or diffusion (degassing). At the tips of marine propellers and in hydraulic machinery, the collapse of cavitation bubbles can cause noise and vibration and lead to surface damage in the form of pitting.
由于局部压力降低而在液体中形成充满蒸汽或气体的空腔,通常原因是流体的加速,例如收敛喷嘴的流动。如果液体中没有溶解气体,当压力降至饱和蒸汽压力以下时,会发生蒸汽空化。如果气泡是由于高温形成的,则该过程称为沸腾。如果存在溶解气体,则由于压力降低、温度升高或扩散(脱气),会发生气穴。在船用螺旋桨尖端和液压机械中,空化气泡的破裂可能会引起噪音和振动,并导致以点蚀形式出现的表面损坏。
Milling 铣削 A machining process, typically for metals and plastics, in which a multi-tooth rotary cutter removes material to produce flat or profiled surfaces, slots, grooves, etc. Milling is a machining process in which metal is removed by a rotating multiple-tooth cutter; each tooth removes a small amount of metal with each revolution of the spindle. Because both workpiece and cutter can be moved in more than one direction at the same time, surfaces having almost any orientation can be machined.
一种加工工艺,通常用于金属和塑料,其中多齿旋转刀具去除材料以产生平坦或异形表面、槽、槽等。金属由旋转多齿刀具去除;主轴每转一圈,每个齿都会去除少量金属。因为工件和刀具可以同时在多个方向上移动,所以几乎可以加工任何方向的表面。
Spring load (Unit N) 弹簧载荷(单位:N) A load exerted on a component by bending, compressing, extending, or twisting an attached spring. Mechanical energy stored in the spring can be released if any constraints on the component are removed.
通过弯曲、压缩、延伸或扭转连接的弹簧而施加在部件上的载荷。如果部件上的任何约束被移除,则可以释放弹簧中存储的机械能。
Mole number (N) 摩尔数(N) The number of moles in a given mass m of a substance, equal to m divided by the molar mass of the substance.
摩尔数物质给定质量m中的摩尔数,等于m除以物质的摩尔质量。
Atom 原子 The smallest unit of matter that has the properties of a chemical element. The simplest description of an atom (Bohr model) is of a compact nucleus surrounded by one or more orbiting electrons.
具有化学元素性质的最小物质单位。原子的最简单描述(玻尔模型)是由一个或多个轨道电子包围的致密原子核。
Scleroscope hardness number (HSc or HSd) 硬化镜硬度值(HSc或HSd) A number related to the height of rebound of a diamond-tipped hammer dropped on the material being tested. It is measured on a scale determined by dividing into 100 units the average rebound of the hammer from a quenched(to maximum hardness) and untempered AISI W5 tool steel test block.
与落在被测材料上的菱形锤的回弹高度相关的数字。通过将锤子从淬火(达到最大硬度)和未淬火的AISI W5工具钢试块上的平均回弹分为100个单位来测量。
Pitch angle (Unit °) 俯仰角(单位°) For a bevel gear, the angle between the axis and the pitch-cone generator.
对于锥齿轮,轴与节锥生成器之间的角度。
Vibration isolation 隔振 The prevention of transmission of vibration from one component of a system to another part of the same system, such as a building or other structure. Isolation may be achieved using dampers (vibration damping) or by active feedback-control methods. Mechanical vibration is often attenuated by means of components immersed in oil such as in dashpots (viscous damping). Vibration suppression can be achieved (a) using dampers and absorbers tuned to a particular frequency to suppress vibratory forces in structures and other systems (passive suppression) or (b) by the measurement of vibration at key locations in a structure and the application of  cancellation forces (active suppression).
防止振动从系统的一个部件传递到同一系统的另一部分,如建筑物或其他结构。可以使用阻尼器(减振)或主动反馈控制方法实现隔离。机械振动通常通过浸入油中的部件来衰减,例如缓冲罐(粘性阻尼)。可以通过(a)使用调谐到特定频率的阻尼器和吸收器来抑制结构和其他系统中的振动力(被动抑制),或(b)通过测量结构中关键位置的振动并施加抵消力(主动抑制),实现振动抑制。
Actuating system 驱动系统 A system in which an electrical, pneumatic or hydraulic input supplied to an actuator produces force, torque, or displacement, usually in a controlled way.
一种系统,其中提供给执行器的电气、气动或液压输入通常以受控方式产生力、扭矩或位移。
Maximum load (Pmax) 最大负载(Pmax) (1) The load having the highest algebraic value in the load cycle. Tensile loads are considered positive and compressive loads negative. (2)Used to determine the strength of a structural member; the load that can be borne before failure is apparent.
(1)负载循环中具有最高代数值的负载。拉伸荷载视为正荷载,压缩荷载视为负荷载。(2)用于确定结构构件的强度;失效前可承受的载荷是明显的。
Magnetic test 磁性测试 Method used to test heat extraction rates of various quenchants. The test works by utilizing the change in magnetic properties of metals at their Curie point–the temperature above which metals lose their magnetism.
用于测试各种淬火剂的热提取率的方法。该测试通过利用金属在居里点(即金属失去磁性的温度)的磁性变化来进行。
Rockwell superficial hardness test 洛氏表面硬度试验 Same as Rockwell hardness test, except that smaller minor and major loads are used.
与洛氏硬度测试相同,只是使用较小的次要载荷和主要载荷。
Least count 最小计数 The smallest value that can be read from an instrument having a graduated scale. Except on instruments provided with a vernier, the least count is that fraction of the smallest division which can be conveniently and reliably estimated; this fraction is ordinarily one-fifth or one-tenth, except where the graduations are very closely spaced.
可从具有刻度尺的仪器中读取的最小值。除配备游标的仪器外,最小计数是可以方便可靠地估计的最小除法的分数;这个分数通常是五分之一或十分之一,除非刻度间隔非常近。
Balance weight 平衡器 A corrective mass used in the static or dynamic balancing of a rotating object.
用于旋转物体的静态或动态平衡的校正质量。
Structural engineering 结构工程 A branch of civil engineering concerned with the design of buildings, dams, bridges, and other large structures.
土木工程的一个分支,涉及建筑物、水坝、桥梁和其他大型结构的设计。
Design heating load (Unit kW) 设计热负荷(单位kW) The heating requirements based on a specified number of heating degree days, or required to maintain a building or other enclosed space at a specified temperature for a given outside temperature.
基于指定的采暖度日数的加热要求,或在给定的外部温度下将建筑物或其他封闭空间保持在指定温度下所需的加热要求。
Pascal’s law 帕斯卡定律 When there is a change in pressure at any point in a confined fluid at rest, there is an equal change at every other point in the fluid volume.
当处于静止状态的受限流体中任何一点的压力发生变化时,流体体积中的每一点的变化都相等。
Eutectic carbide 共晶碳化物 Carbide formed during freezing as one of the mutually insoluble phases participating in the eutectic reaction of ferrous alloys.
在冷冻过程中形成的碳化物,是参与铁合金共晶反应的互不溶相之一。
Kinetic energy 动能 Energy that an object possesses because it is in motion. It is the energy given to an object to set it in motion. On impact, it is converted into other forms of energy such as strain, heat, sound and light.
物体因运动而拥有的能量。它是赋予物体使其运动的能量。撞击时,它被转换成其他形式的能量,如应变、热、声和光。
Honing 珩磨 Honing is a controlled, low-speed sizing and surface-finishing process in which stock is removed by the shearing action to the bonded abrasive grains of a honing stone, or stick. Finish polishing of surfaces and cutting edges in which very fine abrasive powders, such as rouge, are employed. Honing is usually applied to cylindrical surfaces and lapping to flat, but the usage is not consistent.
珩磨是一种受控的低速尺寸和表面精加工工艺,其中通过对珩磨石或棒的粘结磨粒的剪切作用去除原料。表面和切削刃的精抛光,其中使用了非常细的研磨粉,例如胭脂。珩磨通常用于圆柱面,研磨至平面,但用法并不一致。
B-basis B-基础 Mechanical property value above which at least 90% of the population of values is expected to fall, with a confidence of 95%.
机械性能值超过该值时,至少90%的值预计会下降,置信度为95%。
Pressure recovery (Unit Pa) 压力恢复(单位Pa) The progressive increase in static pressure for unseparated flow through a diverging nozzle or diffuser.
通过发散喷嘴或扩散器的未分离流的静压逐渐增加。
Bearing strength 承载强度 The maximum bearing stress that a material is capable of sustaining.
材料能够承受的最大承载应力。
Bypass valve 旁通阀 A valve that directs flow through a bypass.
引导流过旁路的阀门。
Tempered martensite embrittlement 回火马氏体脆化 Embrittlement of ultrahigh-strength steels caused by tempering in the temperature range of 205 to 400 °C (400 to 750 °F); also called 350 °C or 500 °F embrittlement. Tempered martensite embrittlement is thought to result from the combined effects of cementite precipitation on prioraustenite grain boundaries or interlath boundaries and the segregation of impurities at prioraustenite grain boundaries.
超高强度钢在205至400°C(400至750°F)温度范围内回火引起的脆化;也称为350°C或500°F脆化。回火马氏体脆化被认为是由于渗碳体沉淀在原奥氏体晶界或层间晶界上以及杂质在原奥氏体晶粒边界处偏析的综合影响。
Cap A cover, often in the form of a short cylinder, one end of which is closed. Typically used to close an orifice or pipe end, on to which it can be pushed, welded, screwed, or attached with fasteners.
一种盖子,通常为短圆柱体,一端封闭。通常用于封闭孔口或管端,可将其推入、焊接、拧紧或用紧固件连接到其上。
Carbon restoration 碳修复 Replacing the carbon lost in the surface layer from previous processing by carburizing this layer to substantially the original carbon level. Sometimes called recarburizing.
通过将该层渗碳到基本上原始的碳水平来替换先前处理中在表面层中损失的碳。有时称为再碳化。
Wave spring 波形弹簧 A type of compression spring, similar to a coil spring, but made of strip shaped into waves around the circumference.
一种压缩弹簧,类似于螺旋弹簧,但由沿圆周成波浪形的条状物制成。
Cleavage fracture 解理断裂 A fracture, usually of a polycrystalline metal, in which most of the grains have failed by cleavage, resulting in bright reflecting facets. It is one type of crystalline fracture and is associated with low energy brittle fracture. Contrast with shear fracture. A fracture created by splitting (cleavage), as between layers in materials like slate or mica. In brittle metals, and brittle  microconstituents in alloys, cleavage occurs along particular crystal planes.
一种通过分裂(劈裂)产生的裂缝断裂,通常是多晶金属的断裂,其中大部分晶粒因解理而失效,产生明亮的反射面。它是一种结晶性断裂,与低能脆性断裂有关。与剪切断裂相对。如板岩或云母等材料的层之间。在脆性金属和合金中的脆性微量成分中,沿特定晶面发生解理。
Critical crack length (Unit m) 临界裂纹长度(单位米) The crack length at which a given stress applied to a body will result in crack propagation and fracture.
施加到物体上的给定应力将导致裂纹扩展和断裂的裂纹长度。
Stress-intensity calibration 应力强度校准 A mathematical expression, based on empirical or analytical results, that relates the stress-intensity factor to load and crack length for a specific specimen planar geometry. Also known as Kcalibration.
基于经验或分析结果的数学表达式,该表达式将特定试样平面几何形状的应力强度因子与载荷和裂纹长度联系起来。也称为K校准。
Load 负载 For testing machines, a force applied to a test piece that is measured in units such as pound-force, newton, or kilogram-force.
对于试验机,施加在试件上的力,以磅力、牛顿或千克力等单位测量。
Nut 螺母 A metal fastener of square, hexagon or other shape, having an internal thread which screws onto a bolt, stud or arbor. An internally-threaded fastener used with externally-threaded bolts. Usually hexagonal in shape but there is a multitude of other geometries, such as square, for special purposes and different gripping tools.
一种方形、六角形或其他形状的金属紧固件,具有内螺纹,可拧在螺栓、螺柱或心轴上。与外螺纹螺栓一起使用的内螺纹紧固件。通常为六边形,但也有许多其他几何形状,如方形,用于特殊用途和不同的夹持工具。
Failure of the bolt 螺栓失效 Term implying that the bolt has broken or the threads have stripped. There can be many reasons for this.
表示螺栓断裂或螺纹脱落的术语。原因可能有很多种。
Initial stress 初始应力 The stress produced by strain in a specimen immediately on achieving the given constant-strain conditions in a stress-relaxation test before stress-relaxation occurs. Sometimes referred to as instantaneous stress.
在应力松弛发生之前,在应力松弛试验中达到给定的恒定应变条件时,试样立即应变所产生的应力。有时称为瞬时压力。
Surface hardening 表面硬化 A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred.
一个通用术语,涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。
Cavitation-resistance inducer 抗气蚀诱导剂 An axial-flow pump used upstream of a main pump in order to prevent cavitation in the latter by increasing the inlet head.
在主泵上游使用的轴流泵,通过增加进口压头防止主泵出现气穴。
Precipitation heat treatment 沉淀热处理 Artificial aging in which a constituent precipitates from a supersaturated solid solution.
成分从过饱和固溶体沉淀的人工时效。
Deflection temperature under load (DTUL) 负载变形温度(DTUL) The temperature at which a simple cantilever beam deflects a given amount under load. Formerly called heat distortion temperature.
简单悬臂梁在负载下偏转给定量的温度。以前称为热变形温度。
Eyebolt (eyescrew) 吊环螺栓(眼螺丝) A bolt threaded at one end and bent to a loop at the other end. A bolt or screw with a closed loop in place of a head.
一端有螺纹,另一端弯曲成环的螺栓。带有闭合环代替头部的螺栓或螺钉。
Load factor (F) 负载系数(F) The ratio between an increase in bolt tension and the external load which has caused the increase. Factors reflecting the probability of an increase in load in a shear joint. Used in load and resistant factor design.
螺栓张力增加与导致增加的外部载荷之间的比率。反映剪切接缝中荷载增加概率的系数。用于载荷和阻力系数设计。
Decalescence 退色 A phenomenon, associated with the transformation of alpha iron to gamma iron on the heating (superheating) of iron or steel, revealed by the darkening of the metal surface owing to the sudden decrease in temperature caused by the fast absorption of the latent heat of transformation.
一种现象,与铁或钢加热(过热)时α铁向γ铁的转变有关,由于转变潜热的快速吸收导致温度突然降低,金属表面变黑。
Turning 车削 Turning is a machining process for generating external surfaces of revolution by the action of a cutting tool on a rotating workpiece, usually in a lathe. The rotation of a workpiece held against a cutting tool in a lathe to produce components with a circular cross section.
车削是一种机械加工过程,通常在车床上,通过刀具对旋转工件的作用产生旋转外表面。在车床中,工件靠着刀具旋转,以生产具有圆形横截面的部件。
Creep fatigue 蠕变疲劳 The effects of combined creep and fatigue at high homologous temperatures in metals, and in other materials such as polymers having time-dependent behaviour.
金属和其他材料(例如具有时间相关行为的聚合物)在高同源温度下的组合蠕变和疲劳的影响。
Calorizing 热化 Imparting resistance to oxidation to an iron or steel surface by heating in aluminum powder at 800 to 1000 °C (1470 to 1830 °F).
通过在800至1000°C(1470至1830°F)下加热铝粉,赋予铁或钢表面抗氧化性。
Compression 压缩 1. Loading, the principal effect of which is to squeeze and shorten a component or testpiece. 2. The reduction in volume and increase in density of a substance as a consequence of increased pressure.
1.加载,其主要作用是挤压和缩短部件或试件。2.压力增加导致物质体积减少和密度增加。
Failure 失效 The result when a body, component, or structure is incapable of performing the task for which it was designed. The term is often used without reference to what causes failure, such as fracture, buckling, excessive deformation, wear, or erosion. Failure criteria (failure theories, theories of strength) are mathematical expressions for the combinations of stress, strain, or strain energy at which materials fail, which are employed in design to dimension components.
主体、部件或结构无法执行其设计任务时的结果。该术语通常未提及导致失效的原因,如断裂、屈曲、过度变形、磨损或侵蚀。失效准则(失效理论、强度理论)是材料失效时应力、应变或应变能组合的数学表达式,用于部件尺寸设计。
Malleable cast iron 可锻铸铁 A cast iron made by prolonged annealing of white cast iron in which decarburization or graphitization, or both, take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface, hence, “whiteheart malleable;” otherwise, the fracture surface will be dark, hence, “blackheart malleable.” Ferritic malleable has a predominantly ferritic matrix; pearlitic malleable may contain pearlitic, spheroidite or tempered martensite depending on heat treatment and desired hardness.
白口铸铁一种通过长时间退火制成的铸铁,脱碳,石墨化,或两者都发生,以消除部分或全部渗碳体。石墨是回火碳的形式。如果脱碳是主要反应,产品将呈现出较轻的断裂表面,“白心可锻”。否则,断裂表面将变暗,“黑心可锻”。铁素体可锻性材料主要为铁素体基体;根据热处理和所需硬度,珠光体可锻材料可能包含珠光体、球状体或回火马氏体。
Centrifugal 离心式 Acting or moving in a direction away from the axis of rotation of a rotating body.
沿远离旋转体的旋转轴的方向作用或移动。
Torsional shaft vibration 扭轴振动 The rapid back-and-forth angular twisting along a rotating unbalanced shaft which reaches maxima at critical rotation speeds. Shaft eccentricity, unbalanced mass distribution, oscillatory torque, misalignment, etc. all influence torsional vibration.
沿旋转不平衡轴的快速来回角扭转,在临界转速下达到最大值。轴偏心、质量分布不平衡、振荡扭矩、未对准等都会影响扭转振动。
Quick coupling 快速接头 (quick disconnect, fast coupling) A hose connection allowing rapid assembly or disassembly and comprising a socket and a plug incorporating a springloaded locking mechanism.
(快速断开、快速连接)一种软管连接,允许快速组装或拆卸,包括插座和带有弹簧加载锁定机构的插头。
Non-ferrous metal 有色金属 Strictly, all metals and alloys that do not contain iron, but usually taken to mean aluminium- and copper-based alloys.
严格来说,所有不含铁的金属和合金,但通常指铝基和铜基合金。
Pre-stress 预应力 To induce stresses into a component or structure before it is subjected to operating loads.
在部件或结构承受操作载荷之前,将应力引入部件或结构。
Mechanical properties of solid materials 固体材料的力学性能 The strength and stiffness properties of solid materials such as fracture toughness, the moduli of elasticity, percent elongation,
固体材料的强度和刚度特性,例如断裂韧性、弹性模量、伸长率、
Centigrade heat unit 摄氏热量单位 (Celsius heat unit, CHU) An obsolete (i.e. non-SI) unit equal to the energy required to increase the temperature of one pound of pure, air-free water from 14.5°C to 15.5°C at a pressure of one standard atmosphere.
(摄氏热量单位,CHU)一个已被淘汰的(即非国际单位制)单位,等于在一个标准大气压的压力下将一磅纯净的无空气水的温度从14.5°C提高到15.5°C所需的能量.
Mohs hardness test 莫氏硬度测试 A scratch hardness test for determining comparative hardness using 10 standard minerals—from talc (the softest) to diamond (the hardest).
刮擦硬度测试,用于使用从滑石(最软)到钻石(最硬)的10种标准矿物测定比较硬度。
Bearing strain 轴承应变 The ratio of the deformation of the bearing hole, in the direction of the applied force, to the pin diameter in a bearing test.
轴承孔在作用力方向上的变形与轴承测试中销直径的比值。
Induction heating 感应加热 Heating by combined electrical resistance and hysteresis losses induced by subjecting a metal to the varying magnetic field surrounding a coil carrying alternating current.
通过将金属置于承载交流电的线圈周围的变化磁场中而引起的电阻和磁滞损耗的组合加热。
Sample percentage 样本百分比 The percentage of observed values between two stated values of the variable under consideration. It is a point estimate of the percentage of the population between the same two stated values.
所考虑变量的两个规定值之间的观测值百分比。它是对相同两个规定值之间的总体百分比的点估计。
Static equilibrium 静态平衡 A solid body, structure, or physical system (or any subdivided part) will be in static equilibrium, either at rest or moving with constant velocity, if the resultants of all external forces and moments acting on it are zero.
如果作用在固体上的所有外力和力矩的合力为零,则固体、结构或物理系统(或任何细分部分)无论是静止还是以恒定速度移动,都是处于静态平衡。
Catastrophic failure 灾难性故障 A sudden and total failure of a large engineering structure such as an aeroengine, aircraft, space vehicle, bridge, or dam.
大型工程结构(如航空发动机、飞机、航天器、桥梁或水坝)突然完全失效。
Secondary hardening 二次硬化 The process whereby some low-alloy steels, quenched to produce martensite, produce fine precipitates when tempered above 550°C, which inhibit dislocation motion and reverse the trend towards lower strength at higher tempering temperatures.
某些低合金钢经淬火产生马氏体,在550°C以上回火时产生细小沉淀的过程,这抑制了位错运动,扭转了在较高回火温度下强度降低的趋势。
Combustion deposit 燃烧沉积物 Ash, carbon, and other incombustible solids, often due to impurities in the fuel, that build up on any surfaces exposed to products of combustion. They can lead to corrosion, reduced heat transfer and so higher flue-gas temperatures and reduced efficiency.
灰、碳和其他不燃固体,通常是由于燃料中的杂质,在暴露于燃烧产物的任何表面上堆积。它们会导致腐蚀、传热降低,从而导致烟气温度升高和效率降低。
Union (union joint) 活接头 A threaded pipe fitting that allows two pipes to be connected anddetached without the need for either to be rotated, and without damaging the pipe ends.
一种螺纹管件,允许连接和拆卸两个管道,而无需旋转任何一个管道,且不会损坏管道端部。
Oxidizing flame 氧化焰 A gas flame produced with excess oxygen in the inner flame.
在内部火焰中过量氧气产生的气体火焰。
Screw 螺钉 Threaded fastener designed to be used in a tapped or untapped (e.g., wood screw) hole, but not with a nut. A fastener with a screw thread cut or rolled into its cylindrical or conical shank, intended either to cut its own thread (as in a wood screw) or engage in a threaded hole. A self-tapping screw (sheet-metal screw, tapping screw) has a sufficiently hard thread that it cuts an internal thread in thin sheet or a component made of soft material when driven into a hole in the sheet or component. The screw head is the part of a screw used to apply torque to the screw. Common screw-head designs are circular in cross section with a diametral slot or cross, or hexagonal and recessed with a cross or hexagon. A screw thread is one or more continuous helical grooves of uniform section along either the exterior surface (male thread) or the interior surface (female thread) of a cylindrical or conical body. The three-dimensional shape that results when the thread cross section is rotated and axially advanced along an axis is called a helicoid, the angle that the thread makes when projected on to the axis being called the angle of inclination. Threads are employed in fasteners such as bolts, nuts, and screws; location and measuring instruments; in power drives; in some electrical fittings (Edison thread); and on the ends of crankshafts to suppress oil leakage (thrower thread). Parallel threads are formed on cylinders; tapered threads on cones, typically with a taper rate of 1:16. A screw with a righthanded thread appears to move away from the observer when turned clockwise. All standard screws, bolts and nuts have right-hand threads, but left-handed threads are sometimes employed. The axial distance between corresponding points on adjacent threads is called the screw pitch or screw rate and, for a single continuous helical groove (a single-start thread), is the same as the change in axial distance (the lead) between a nut and the head of a bolt during one revolution, the number of thread forms per mm then being the reciprocal of the pitch. For the same screw diameter, coarse threads have fewer threads per mm than fine threads. A multiple-start screw thread (usually coarse, see later) consists of two or more identical threads running simultaneously along its axis so as to provide greater bearing area and greater velocity ratio. The starts are separated by 180° (double start), 120° (triple start), 90° (quadruple start) etc., depending upon the number of threads. Thus, in double-start threads, the lead is twice the pitch; and so on. The axial distance between corresponding points on two adjacent threads in a multiple start thread is called the divided pitch. The position on a screw thread where there is equal distance between the flanks on the solid part of the thread and in the space between the threads is the pitch point, the associated diameter of which is termed the pitch diameter. The basic nomenclature for threads, some of which is common with that for toothed gearing, is shown in the diagrams. A helix formed or cut on a cylindrical surface which may advance along the axis to the right or left. The helix may be single or multiple.
一种螺纹紧固件,设计用于攻丝或未攻丝(如木螺钉)孔,但不与螺母配合使用。其螺纹被切割或卷成圆柱形或锥形柄,用于切割自身螺纹(如木螺钉)或嵌入螺纹孔。自攻螺钉(钣金螺钉、自攻螺钉)具有足够硬的螺纹,当打入薄板或部件中的孔时,它会在薄板或软材料部件中切割内螺纹。螺钉头是螺钉的一部分,用于向螺钉施加扭矩。常见的螺钉头设计为横截面为圆形,带有直径槽或十字,或为六边形,并带有十字或六边形凹槽。螺纹是沿圆柱形或锥形体的外表面(外螺纹)或内表面(内螺纹)具有均匀截面的一个或多个连续螺旋槽。当螺纹横截面旋转并沿轴轴向前进时产生的三维形状称为螺旋面,螺纹投影到轴上时形成的角度称为倾角。螺纹用于紧固件,如螺栓、螺母和螺钉;定位和测量仪器;在动力驱动中;在一些电气配件中(爱迪生螺纹);并安装在曲轴端部,以抑制漏油(抛掷器螺纹)。在圆柱体上形成平行螺纹;圆锥上的锥形螺纹,通常具有1:16的锥形率。当顺时针旋转时,具有右手螺纹的螺钉似乎会远离观察者。所有标准螺钉、螺栓和螺母都有右手螺纹,但有时使用左手螺纹。相邻螺纹上对应点之间的轴向距离称为螺距或螺纹率,对于单个连续螺旋槽(单个起始螺纹),与螺母和螺栓头之间的轴向间距(导程)在一周内的变化相同,每mm的螺纹形式数为螺距的倒数。对于相同的螺钉直径,粗螺纹的每毫米螺纹数少于细螺纹。多头螺纹(通常为粗螺纹,见下文)由两个或多个沿其轴线同时延伸的相同螺纹组成,以提供更大的承载面积和更大的速比。根据螺纹的数量,起点之间的间隔为180°(双起点)、120°(三起点)、90°(四起点)等。因此,在双起始螺纹中,导程是螺距的两倍;多起点螺纹中两个相邻螺纹上对应点之间的轴向距离称为分割螺距。螺纹上的位置,即螺纹实体部分的侧面和螺纹之间的空间之间的距离相等,即节点,其相关直径称为节径。图中显示了螺纹的基本术语,其中一些与齿轮传动的基本术语相同。在圆柱面上形成或切割的螺旋线,可沿轴线向右或向左前进。螺旋可以是单个或多个。
Orange peel 橘皮 A surface roughening in the form of a pebble-grained pattern where a metal of unusually coarse grain is stressed beyond its elastic limit. Also known as pebbles and alligator skin.
一种以卵石颗粒图案形式出现的粗糙化表面,其中晶粒异常粗的金属受到的应力超过其弹性极限。也称为卵石和鳄鱼皮。
Chain dimensioning 链条尺寸标注 On an engineering drawing, where the end point of one dimension is the starting point for the next. Parallel dimensioning is preferred as chain dimensioning can lead to the accumulation of tolerances.
在工程图纸上,其中一个尺寸的终点是下一个的起点。平行尺寸标注是首选,因为链尺寸标注可能导致公差累积。
Shear strength (Unit Pa) 抗剪强度(单位Pa) The maximum shear stress that can be withstood by a material either (a) before plasticity occurs or (b) before rupture.
材料在(a)塑性发生之前或(b)断裂之前能够承受的最大剪切应力。
Ion carburizing 离子渗碳 A method of surface hardening in which carbon ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma carburizing or glowdischarge carburizing.
一种表面硬化方法,利用高压电能将碳离子在真空中扩散到工件中。与等离子渗碳或辉光放电渗碳同义。
Hydraulic air compressor 液压空气压缩机 1. A compressor powered by a hydraulic motor. 2. A device in which air is compressed as a result of being entrained in water flowing in a downcomer pipe. The compressed air is released in a chamber at the bottom of the pipe.
1. 由液压马达驱动的压缩机。2.一种装置,其中空气由于夹带在降液管中流动的水中而被压缩。压缩空气在管道底部的腔室中释放。
Fit 装配 The general term used to signify the range of tightness which may result from the application of a specific combination of allowances and tolerances in the design of mating parts.
通用术语,用于表示配合零件设计中公差和公差的特定组合可能导致的紧密性范围。
Lead of thread 螺纹导程 On a single threaded screw, the distance the screw or nut advances in one complete revolution.
在单螺纹螺钉上,螺钉或螺母在一整圈中前进的距离。
Scragging machine 刮擦机 1. A machine to test springs by impulsive loading 2. A machine to increase the service life of coil springs by compressing them to their minimum solid length before use, thereby inducing favourable residual stresses.
1.一种通过冲击载荷测试弹簧的机器2.一种在使用前将螺旋弹簧压缩至其最小实心长度以提高其使用寿命的机器,从而产生有利的残余应力。
Barometer 气压计 An instrument used to measure atmospheric pressure. An instrument for measuring atmospheric pressure. There are two main types – the mercury barometer, and the aneroid barometer.
用于测量大气压力的仪器。有两种主要类型——水银气压计和无液气压计。
Tensile test (tension test) 拉伸试验(拉力试验) A test in which a precisely-machined tensile specimen (tensile testpiece), typically circular or rectangular in cross section with large end sections that are gripped in the testing machine, is subjected to an increasing tensile load, usually to the point of fracture, to produce a stress–strain curve from which such material properties as modulus of elasticity, limit of proportionality, proof stress, yield point, and ultimate tensile stress can be determined. The relevant standard is ISO 6892-1.
一种试验,在这种试验中,精密加工的拉伸试样(拉伸试件)的横截面通常为圆形或矩形,具有在试验机中夹紧的大端部,受到越来越大的拉伸载荷,通常达到断裂点,以产生应力-应变曲线,从中可以看出弹性模量、比例极限等材料特性,可以确定验证应力、屈服点和极限拉伸应力。相关标准为ISO 6892-1。
Bearing stress 承受应力 The force per unit of bearing area.
每单位承载面积的力。
Combined dimensioning 组合尺寸标注 The use of chain dimensioning and parallel dimensioning on the same engineering drawing.
在同一工程图上使用链式尺寸标注和平行标注。
Boyle’s law 波义耳定律 The product of the pressure of a gas p and its volume is constant at a given absolute temperature T. Together with Charles law, it yields the ideal gas equation p = Mrt where m is the mass of gas and R is the specific gas constant. The volume of a gas at constant temperature is inversely proportional to the pressure. This means that as pressure increases, the volume of a gas decreases.
在给定的绝对温度T下,气体的压力p与其体积的乘积是恒定的。与查尔斯定律一起,它产生了理想的气体方程p=Mrt,其中m是气体的质量,R是特定的气体常数。恒温下气体的体积与压力成反比。这意味着随着压力的增加,气体的体积会减少。
Crosshead 十字头 1. A reciprocating member, sliding between guides, to which the piston rod is firmly attached on one side and to which the connecting rod is pinned on the other for the conversion of reciprocating into rotary motion. 2. The moveable beam in early designs of mechanical testing machines. 3. A screwhead having slots in a + shape that takes a mating screwdriver.
1.一种往复式构件,在导轨之间滑动,活塞杆一侧固定在其上,连杆另一侧固定在该构件上,用于将往复式运动转换为旋转运动。2.机械试验机早期设计中的活动梁。3.一种螺钉头,其具有采用配合螺丝刀的+形槽。
Achme thread Achme螺纹 A screw thread having an included angle of 29° and largely used for feed screws on machine tools.
一种夹角为29°的螺纹,主要用于机床上的进给丝杠。
Absolute zero 绝对零度 Temperature of -273.16″C or 459.69″F or OK at which molecular motion vanishes and a body has no heat energy.
温度为-273.16″C或459.69″F,此时分子运动消失且物体没有热能。
Design stress (Unit Pa) 设计应力(单位Pa) The greatest allowable stress in a component or structure that will not result in failure under normal operating conditions.
在正常操作条件下不会导致失效的部件或结构中的最大许用应力。
Eccentric load 偏心载荷 The external load on a fastener or groups of fasteners is said to be eccentric if the resultant of that load does not pass through the centroid of the group of fasteners (eccentric shear load ) or does not coincide with the bolt axis (eccentric tensile load ).
如果一个或多个紧固件上的外部载荷的合力未穿过紧固件组的质心(偏心剪切载荷)或与螺栓轴不重合(偏心拉伸载荷),则称该外部载荷为偏心。
Embrittlement 脆化 The loss of ductility or fracture toughness of materials, either during processing or in service. The severe loss of ductility or toughness or both, of a material, usually a metal or alloy. Many forms of embrittlement can lead to brittle fracture. Many forms can occur during thermal treatment or elevated-temperature service (thermally induced embrittlement). Some of these forms of embrittlement, which affect steels, include blue brittleness, 885 °F (475 °C) embrittlement, quench-age embrittlement, sigma-phase embrittlement, strain-age embrittlement, temper embrittlement, tempered martensite embrittlement, and thermal embrittlement. In addition, steels and other metals and alloys can be embrittled by environmental conditions (environmentally assisted embrittlement). The forms of environmental embrittlement include acid embrittlement, caustic embrittlement, corrosion embrittlement, creep-rupture embrittlement, hydrogen embrittlement, liquid metal embrittlement, neutron embrittlement, solder embrittlement, solid metal embrittlement, and stress-corrosion cracking.
材料在加工或使用过程中的延展性或断裂韧性损失。通常是金属或合金的延展性或韧性或两者的严重损失。多种形式的脆化可导致脆性断裂。在热处理或高温服务期间,可能会出现多种形式(热致脆化)。影响钢的一些脆化形式包括蓝脆、885°F(475°C)脆化、淬火时效脆化、西格玛相脆化、应变时效脆化,回火脆化、回火马氏体脆化和热脆化。此外,钢和其他金属和合金可能因环境条件而脆化(环境辅助脆化)。环境脆化的形式包括酸脆化、碱脆化、腐蚀脆化、蠕变断裂脆化、氢脆化、液态金属脆化、中子脆化、焊料脆化、固态金属脆化和应力腐蚀开裂。
Size effect 尺寸效应 Effect of the dimensions of a piece of metal on its mechanical and other properties and on manufacturing variables such as forging reduction and heat treatment. In general, the mechanical properties are lower for a larger size.
金属件的尺寸对其机械和其他性能以及对制造变量(如锻造、压下和热处理)的影响。一般来说,尺寸越大,机械性能越低。
Inch-pound force/inch² 英寸磅力/英寸² A non-SI unit for the specific work of fracture (fracture toughness). The conversion to SI is 1 in.lbf/in² = 1.751 268 × 102 J/m².
用于特定断裂功(断裂韧性)的非国际单位制单位。到SI的转换为1英寸。lbf/in²=1.751268×102J/m²。
Strength (Unit Pa) 强度(单位Pa) The maximum stress, in tension, compression, shear, or combinations thereof, that may be monotonically applied to a material, component, or structure before failure (defined as fracture, yielding, buckling, etc. as appropriate).
在破坏前(视情况定义为断裂、屈服、屈曲等),材料、部件或结构在拉伸、压缩、剪切或其组合中可能单调施加的最大应力。
Steady pin 定位销 A dowel, key, or pin that prevents a pulley from turning on its shaft.
防止滑轮在其轴上转动的销钉、键或销。
Horsepower 马力 Unit indicating the rate at which work is done. The electrical equivalent of one horsepower is 746 watts.
单位表示完成工作的速率。一马力的电当量为746瓦。
Check valve 止回阀 (clack valve, non-return valve) A mechanical device that allows fluid flow in one direction only. The numerous designs include ball, diaphragm, disc, lift, split disc, and swing check valves.
(瓣阀、止回阀)一种仅允许流体单向流动的机械装置。众多设计包括球阀、隔膜阀、盘阀、升降阀、分体盘阀和旋启式止回阀。
Degradation 降解 The reduction with time of the physical properties of a material.
材料的物理性质随时间的减少。
Elongation 伸张率 A term used in mechanical testing to describe the amount of extension of a test piece when stressed.
机械测试中使用的术语,用于描述试样在受力时的延伸量。
Sampling frequency (Unit Hz) 采样频率(单位Hz) (sampling rate) The number of measurement samples per unit time taken from a continuous analogue signal to produce a discrete signal. It is the inverse of the time between successive measurements (sampling interval, sampling period, or sampling time).
(采样率)从连续模拟信号中提取以产生离散信号的每单位时间的测量样本数。它是连续测量之间时间的倒数(采样间隔、采样周期或采样时间)。
Alternative energy 可替代能源 (alternate energy) Energy sources that are renewable and do not have the undesired consequences of fossil fuels and nuclear energy.
(替代能源)可再生能源,不会产生化石燃料和核能的不良后果。
Biodiesel 生物柴油 A substitute for diesel fuel derived from the oily seeds of sunflowers, oilseed rape, soya beans, etc.
从向日葵、油菜、大豆等的油性种子中提取的柴油的替代品。
AISC AISC The American Institute of Steel Construction.
美国钢结构学会。
Bias pressure (Unit Pa) 偏压(单位Pa) In a fluidic device controlled by pressure difference, the magnitude of that difference.
在由压力差控制的流体装置中,该差值的大小。
Diaphragm meter 隔膜计 A dry flow meter in which there are two or more interconnected chambers, each having a diaphragm in the wall. The chambers empty and fill alternately and the flow rate of gas is determined from the movement of diaphragms. Diaphragm meters are commonly used to monitor domestic and commercial gas supply.
一种干式流量计,其中有两个或多个相互连接的腔室,每个腔室的壁上都有一个隔膜。腔室交替排空和填充,气体流速由隔膜的移动确定。隔膜流量计通常用于监测家用和商用燃气供应。
Ion nitriding 离子氮化 A method of surface hardening in which nitrogen ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma nitriding or glowdischarge nitriding.
一种表面硬化方法,其中氮离子通过使用高压电能在真空中扩散到工件中。与等离子体氮化或辉光放电氮化同义。
Modulus of resilience 回弹系数 The amount of energy stored in a material when loaded to its elastic limit. It is determined by measuring the area under the stress-strain curve up to the elastic limit.
当加载到其弹性极限时,材料中储存的能量量。通过测量应力-应变曲线下直至弹性极限的面积来确定。
Crank angle (Unit °) 曲柄角度(单位°) The angle between the crank of a slider-crank mechanism and a line from the crankshaft centreline to the piston axis.
曲柄滑块机构的曲柄与曲轴中心线到活塞轴线的直线之间的角度。
Notch strength 缺口强度 The maximum load on a notched tensile-test specimen divided by the minimum cross-sectional area (the area at the root of the notch). Also known as notch tensile strength.
缺口拉伸试样上的最大载荷除以最小横截面积(缺口根部的面积)。也称为缺口抗拉强度。
Fracture mechanics 断裂力学 The stress analysis of bodies containing cracks. The use of stressconcentration factors and other correction factors of traditional strength of materials is inadequate when flaws are present initially (or develop during loading), since fracture depends not only on stress but also the size of the crack. Traditional strength of materials stress calculations cannot predict either the safe working stress in the presence of a known flaw, or the critical size of flaw just tolerable with a given working stress.
含裂纹物体的应力分析。当初始存在缺陷(或在加载过程中形成缺陷)时,使用应力集中系数和传统材料强度的其他修正系数是不够的,因为断裂不仅取决于应力,还取决于裂纹的大小。传统的材料强度应力计算既不能预测已知缺陷存在时的安全工作应力,也不能预测给定工作应力下可容忍的缺陷临界尺寸。
Collapse load (Unit N) 毁坏荷载(单位N) The applied load at which a structure becomes a mechanism owing to the formation of sufficient plastic hinges for collapse to occur.
由于形成足够的塑性铰链以发生坍塌,结构成为机制的施加载荷。
Cap nut 盖型螺母 A nut with a blind threaded hole, for example a dome nut to cover the end of a bolt.
带有盲螺纹孔的螺母,例如用于覆盖螺栓末端的圆顶螺母。
Angle of friction 摩擦角 (friction angle, β) (Unit °) For a body in contact with a plane surface, the angle between the normal to the surface and the resultant force between the body and the surface. If the friction force is F and normal force is N, β is given by F/N = μ = tan β where μ is the coefficient of friction.
(摩擦角,β)(单位°)对于与平面接触的物体,表面法线与物体与表面之间的合力之间的夹角。如果摩擦力为F,法向力为N,则β由F/N=μ=tanβ给出,其中μ是摩擦系数。
Compression stroke 压缩冲程 The stroke in a reciprocating compressor or engine during which the working fluid is compressed.
往复式压缩机或发动机中工作流体被压缩的冲程。
Clamping force 夹紧力 The equal and opposite forces which exist at the interface between two joint members. The clamping force is created by tightening the bolts, but is not always equal to the combined tension in the bolts. Hole interference problems, for example, can create a difference between clamping force and bolt loads.
存在于两个连接构件之间的界面处的相等和相反的力。夹紧力是通过拧紧螺栓产生的,但并不总是等于螺栓中的组合张力。例如,孔干涉问题可能会在夹紧力和螺栓载荷之间产生差异。
Coining 压印 A forging operation, employing a closely-fitting punch and die from which no metal is allowed to escape, in which the surface pattern on the punch and die is imprinted on the blank.
一种锻造操作,采用紧密配合的凸模和模具,不允许金属逸出,其中凸模和模具上的表面图案印在坯料上。
Bearing failure 轴承故障 A failure that occurs in a riveted or bolted joint when the transverse load divided by the bearing area results in a stress that leads to permanent plastic deformation.
当横向载荷除以承载面积产生导致永久塑性变形的应力时,铆接或螺栓连接中发生的失效。
Turbo generator 涡轮发电机 (turboset) The combination of a steam or gas turbine and an electrical generator with a single shaft or connected coaxial shafts.
(汽轮发电机组)蒸汽或燃气轮机与发电机的组合,具有单轴或连接的同轴。
Slip joint 滑动接头 A mechanical connection which allows limited endwise relative movement of two components such as pipes, rods, and ducts.
一种机械连接,允许两个部件(如管道、杆和管道)进行有限的轴向相对运动。
Interrupted quenching 间断淬火 A quenching procedure in which the workpiece is removed from the first quench at a temperature substantially higher than that of the quenchant and is then subjected to a second quenching system having a different cooling rate than the first.
在该淬火过程中,工件在显著高于淬火剂的温度下从第一次淬火中取出,然后经受具有不同于第一次淬火的冷却速率的第二次淬火系统。
Transverse direction 横向 Literally, the “across” direction, usually signifying a direction or plane perpendicular to the direction of working. In rolled plate or sheet, the direction across the width is often called long transverse, and the direction through the thickness, short transverse.
从字面上看,“横穿”方向,通常表示与工作方向垂直的方向或平面。在轧制钢板或薄板中,横跨宽度的方向通常称为长横向,穿过厚度的方向称为短横向。
Heat tinting 热着色 Coloration of a metal surface through oxidation by heating to reveal details of the microstructure.
通过加热氧化使金属表面着色,以揭示微观结构的细节。
Vickers hardness number 维氏硬度值 (diamond hardness number, DHN, VHN, VPN) (Unit kg/mm² originally, sometimes now Pa) Indentation hardness given by load divided by the surface area of the permanent impression obtained when the indenter is in the form of a square pyramid whose opposite faces make an angle of 136° with one another. The mean length d of the diagonals of the indentation is determined, from which VPN = 0.927(2W/d2) where W is the load, since the base of the pyramid has an area equal to 0.927 times the surface area.
(金刚石硬度值,DHN,VHN,VPN)(最初单位为kg/mm²,有时为Pa)压痕硬度,由载荷除以永久压痕的表面积得出,当压头呈方形棱锥体形式时,其相对面彼此成136°角。确定压痕对角线的平均长度d,其中VPN=0.927(2W/d2),其中W是载荷,因为棱锥底部的面积等于表面积的0.92七倍。
Retaining clip 固定夹 (R-clip, hair cotter pin) A wire clip roughly with the shape of the letter R. The straight part of the clip passes through a hole drilled into a shaft or rod such that a wheel is held in position on the shaft, or the shaft is prevented from moving axially.
(R形夹,开口销)大致与字母R形状相同的线夹。线夹的直线部分穿过钻在轴或杆上的孔,从而将车轮固定在轴上,或防止轴轴向移动。
Compression wave 压缩波 (dilatation wave) In a fluid or a solid, a progressive wave or wavefront that compresses the medium through which it propagates.
(膨胀波)在流体或固体中,压缩介质传播的行波或波前。
Spherical washer 球面垫圈 A washer whose upper surface is semispherical. Used with a nut whose contact face is also semispherical. Reduces bending stress in a bolt or stud, by allowing some self-alignment and some compensation for nonparallel joint surfaces or Angularity.
上表面为半球形的垫圈。与接触面也是半球形的螺母一起使用。减少螺栓或螺柱中的弯曲应力,允许一些自对准,并对不平行的接头表面或角度进行一些补偿。
Velocity defect (Unit m/s) 速度亏损(单位:m/s) In a viscous flow, such as a boundary layer or wake, the reduction in velocity, due to friction, compared with that of the free stream.
在粘性流中,如边界层或尾迹,由于摩擦,与自由流相比,速度降低。
Initial preload 初始预载 The tension created in a single bolt as it is tightened. Will usually be modified by subsequent assembly operations or by in-service loads and conditions.
拧紧单个螺栓时产生的张力。通常会通过后续的装配操作或在役负载和条件进行修改。
Water-jet cutting 水射流切割 Cutting of materials such as rock by means of a high-speed jet of water containing abrasive particles.
通过含有磨料颗粒的高速水射流切割岩石等材料。
Coarse threads 粗螺纹 Threads with relatively large separation between corresponding points on the threads.
螺纹上相应点之间的间距相对较大的螺纹。
Flattening test 压扁试验 This term as applied to tubing refers to a method of testing a section of tubing by flattening it until the inside walls are parallel and separated by a given distanceusually equal to three times the wall thickness for seamless tubes and five times the wall thickness for lap-welded tubes. Boiler tubes subjected to this test should show no cracks or flaws. The flattening test applied to rivets, consists in flattening a rivet head while hot to a diameter equal to 21⁄2 times the diameter of the shank or body of the rivet. Good rivet steel must not crack at the edges of the flattened head.
该术语适用于管材,是指通过压扁管材直至内壁平行并隔开给定距离(通常等于无缝钢管壁厚的三倍,搭接焊管壁厚的五倍)来测试管材截面的方法。进行该试验的锅炉管应无裂纹或缺陷。适用于铆钉的压扁试验包括在热态下压扁铆钉头,使其直径等于铆钉柄或铆钉体直径的21⁄2倍。良好的铆钉钢不得在扁平头部边缘开裂。
Brine quenching 盐水淬火 A quench in which brine (salt water-chlorides, carbonates, and cyanides) is the quenching medium. The salt addition improves the efficiency of water at the vapor phase or hot stage of the quenching process.
一种淬火,其中盐水(盐水-氯化物、碳酸盐和氰化物)是淬火介质。添加盐提高了水在淬火过程的气相或热阶段的效率。
Time quenching 时间淬火 A term used to describe a quench in which the cooling rate of the part being quenched must be changed abruptly at some time during the cooling cycle.
用于描述淬火的术语,其中被淬火零件的冷却速率必须在冷却循环的某个时间突然改变。
Vane engine (vane motor) 叶片发动机(叶片马达) A rotary engine in which high-pressure hydraulic fluid in the spaces between spring-loaded sliding vanes held in an offset rotor acts on the vanes, causing the rotor to revolve within a cylinder. The design is much like a sliding-vane compressor, as is that of a vane pump, used to pump liquids.
一种旋转式发动机,其中偏置转子中装有弹簧的滑动叶片之间的高压液压流体作用在叶片上,使转子在气缸内旋转。这种设计很像滑动叶片压缩机,就像用于泵送液体的叶片泵一样。
Fastener with waisted shank 带腰柄的紧固件 Finished fastener with a shank diameter of ds < d2.
柄径ds
Joint 关节接合处 The part of a robot arm permitting either rotational or translational motion. Each joint provides a single degree of freedom, and thus a minimum of six is required if the robot is to be able to position and orientate the end effector anywhere within the workspace. A joint is described by four parameters: the joint angle, joint offset, joint twist, and link length. The joint angle is the angle between an extrapolation of the previous link length and the present link length, measured positive anticlockwise in a plane normal to the joint axis. This is variable in a rotational joint and fixed in a translational joint. The joint offset is the distance between the link length for the previous link and that for the present link, measured along the joint axis. This is variable for a translational joint and fixed for a rotational joint. The joint twist for the nth joint is the angle between the axes of joints Jn and Jn+1, measured positive anticlockwise in a plane normal to the link length and viewed from the position of the Jn+1 joint. The link length is the mutually perpendicular distance between planes passing through the axes of joint Jn and Jn+1. Both the joint twist and link length are fixed in all joints.
机器人手臂上允许旋转或平移运动的部分。每个接合处都有自由度,如果机器人要能够在工作空间内的任何位置定位和定向末端执行器,则至少需要六个接合处具有自由度。关节接合处由四个参数描述:关节角度、关节偏移、关节扭曲和链接长度。关节角度是在垂直于关节轴的平面内逆时针测量的先前连杆长度和当前连杆长度的外推之间的角度。这在旋转关节中是可变的,在平移关节中是固定的。关节偏移是沿关节轴测量的前一个连杆和当前连杆的连杆长度之间的距离。这对于平移关节是可变的,对于旋转关节是固定的。第n个关节的关节扭曲是关节Jn和Jn+1轴之间的角度,在垂直于连杆长度的平面内逆时针测量,从Jn+2关节的位置观察。连杆长度是穿过关节轴Jn和Jn+1的平面之间相互垂直的距离。关节扭曲和连杆长度在所有关节中都是固定的。
Computational domain 计算域 In CFD, FEM, and other numerical methods, the area or volume within which calculations are performed and on the periphery of which the boundary conditions are specified.
在CFD、FEM和其他数值方法中,执行计算的区域或体积以及在其外围指定边界条件的区域或体积。
Nanoparticles 纳米颗粒 Particles with dimensions of order 1 nm which have either been introduced into microstructures for reinforcement or are present as impurities.
尺寸为1nm级的颗粒,其已被引入微结构中用于增强或作为杂质存在。
Normal temperature and pressure (NTP) 常温常压(NTP) Reference conditions defined by NIST as 20°C and 1 atm.
NIST定义的参考条件为20°C和1atm。
Acoustic droplet ejection 声液滴喷射 The ejection of small droplets from the surface of a liquid that results from focusing high-intensity ultrasound near the surface.
由于在表面附近聚焦高强度超声波而从液体表面喷射出小液滴。
Pitch (Unit m) 间距(单位:m) 1. In a cascade of identical turbine or compressor blades, the distance between successive blades measured parallel to the leading edges. 2. For a screw thread, the distance between adjacent thread forms measured parallel to the thread axis. 3. For an aircraft, the vertical relationship between the nose and the horizon. The pitch axis is an axis in the plane of the wings of an aircraft, perpendicular to the centreline, about which the aircraft rotates. Pitch motion is the corresponding up or down movement of the aircraft nose. Pitch attitude is the angle between the centreline of an aircraft and the horizontal. The angle is positive when the nose is above its position when the centreline is horizontal.
1.在相同涡轮或压缩机叶片的叶栅中,平行于前缘测量的连续叶片之间的距离。2.对于螺纹,平行于螺纹轴线测量的相邻螺纹形状之间的距离。3.对于飞机,机头和水平线之间的垂直关系。俯仰轴是飞机机翼平面内垂直于中心线的轴,飞机绕中心线旋转。俯仰运动是飞机机头的相应向上或向下运动。俯仰姿态是飞机中心线与水平线之间的角度。当中心线水平时,当机头高于其位置时,角度为正。
Knoop hardness test 努氏硬度试验 An indentation-hardness test using calibrated machines to force a rhombic-based pyramidal diamond indenter having specified edge angles, under specified conditions, into the surface of the material under test and to measure the long diagonal after removal of the load. An indentation hardness test in which the indenter is an elongated diamond pyramid that gives an impression in the form of a parallelogram, in which the longer diagonal is about seven times the shorter. Used for studies of anisotropy in solid materials.
使用校准机器进行的一种压痕硬度试验,在规定条件下,将具有规定边缘角的菱形棱锥金刚石压头压入受试材料表面,并在移除荷载后测量长对角线。其中压头是一个细长的菱形棱锥,以平行四边形的形式给出压痕,其中较长的对角线约为较短的七倍。用于研究固体材料的各向异性。
Tyre 轮胎 A flexible ring-shaped cover mounted on a wheel rim that supports the weight of a vehicle, such as a motor vehicle, aircraft, or bicycle, and transmits power and torque to a road surface. Some pneumatic tyres are inflated directly, others have a separate inner tube that is inflated. For certain applications, solid tyres are used.
车轮罩安装在轮辋上的柔性环形罩,用于支撑车辆(如机动车、飞机或自行车)的重量,并将动力和扭矩传递到路面。有些充气轮胎是直接充气的,有些轮胎有单独的内胎充气。对于某些应用,使用实心轮胎。
Tension joint 张力接头 A joint which is primarily subjected to loads acting more or less parallel to the axes of the bolts.
主要承受或多或少平行于螺栓轴线的载荷的接头。
Feather key 滑键 A parallel key fastened in either the shaft or in the hub of a member sliding on it. When fastened in the shaft, it must be long enough to hold or drive the sliding member in any of its positions on the shaft. When in the sliding member the key need only be as long as the hub.
一种平行键,固定在轴上或在其上滑动的构件的轮毂上。当固定在轴上时,其长度必须足以将滑动构件固定或驱动在轴上的任何位置。当处于滑动构件中时,键只需与轮毂一样长。
Austenite-stabilizer 奥氏体稳定剂 Alloying element expanding the γ-phase field in the corresponding phase diagram, which manifests itself in a decrease of the A3 temperature and an increase of the A4 temperature in binary alloys Fe–M as well as in a decrease of A1 temperature in ternary alloys Fe–C–M (M is an alloying element). The solubility of austenite-stabilizers in ferrite is much lower than in austenite. Under the influence of austenite-stabilizers, austenite can become thermodynamically stable down to room temperature.
合金元素扩展了相应相图中的γ相场,这表现为二元合金Fe-M中A3温度的降低和A4温度的升高,以及A1温度的降低三元合金Fe–C–M(M是合金元素)。奥氏体稳定剂在铁素体中的溶解度远低于在奥氏体中的溶解度。在奥氏体稳定剂的影响下,奥氏体可以在低至室温时变得热力学稳定。
Crushing strain 压应变 The supposed single strain that results in comminution of a brittle material. The corresponding stress is termed the crushing strength. Neither quantity can be a material constant as they must obey the laws of fracture mechanics and will depend on the type of testpiece, method of loading etc.
导致脆性材料粉碎的假定单应变。相应的应力称为抗压强度。这两个量都不能是材料常数,因为它们必须遵守断裂力学定律,并取决于试件类型、加载方法等。
Shim 垫片 A thin piece of material, such as metal of accurately-known thickness, placed between two surfaces to ensure they are the correct distance apart. A thin piece of material placed between two surfaces to obtain a proper fit, adjustment, or alignment. The piece can also be analyzed to measure furnace carbon potential (that is, because while in the furnace it will quickly carburize to a level equal to the furnace carbon potential).
一块薄的材料,如厚度精确已知的金属,放置在两个表面之间,以确保它们之间的距离正确。放置在两个表面之间以获得适当配合、调整或对齐的一块薄材料。还可以对工件进行分析,以测量熔炉碳势(也就是说,在熔炉中,工件将快速渗碳至与熔炉碳势能相等的水平)。
Bernoulli’s law 伯努利定律 For a steadily flowing fluid (liquid or gas), the sum of the pressure, kinetic energy per unit volume and potential energy per unit volume is constant at any point in the fluid. Using this relationship, it is possible to measure the velocity of a fluid by measuring its pressure at two points, as with a manometer or Pitot tube.
对于稳定流动的流体(液体或气体),压力、每单位体积的动能和每单位体积的势能之和在流体中的任何点都是恒定的。使用这种关系,可以通过在两个点测量流体的压力来测量流体的速度,就像使用压力计或皮托管一样。
Critical load (Unit N) 临界负荷(单位N) 1. The applied load that causes propagation of an existing crack of known length, and hence fracture of a component or structure. 2. The applied load that results in buckling of a column of given end fixity.
1.导致已知长度的现有裂纹扩展并因此导致部件或结构断裂的施加荷载。2.导致具有给定端部固定性的柱屈曲的施加荷载。
Shear strain rate(Unit 1/s) 剪切应变率(单位1/s) In the deformation of solids, the rate at which shear strain is applied in a test or changes with time in a loaded component or structure.
在固体变形中,在试验中施加剪切应变的速率,或在加载部件或结构中随时间变化的速率。
Failure of the joint 连接失效 Failure of a bolted joint to behave as intended by the designer. Failure can be caused or accompanied by broken or lost bolts, but can also mean joint slip or leakage from a gasketed joint even if all bolts still remain whole and in place. Common reasons for joint failure include vibration loosening, poor assembly practices, improper design, unexpected service loads or conditions, etc.
螺栓连接未达到设计者的预期性能。故障可能由螺栓断裂或丢失引起或伴随而来,但也可能意味着即使所有螺栓仍保持完整和就位,也存在接头滑动或垫圈接头泄漏。接头故障的常见原因包括振动松动、装配不当、设计不当、意外的工作负载或条件等。
Flexural strength 抗弯强度 The maximum stress in the outer fiber at the moment of crack or break.
断裂或断裂时刻外层纤维的最大应力。
Crankshaft 曲轴 The main shaft, of which the cranks are a part, of a reciprocating single-or multi-cylinder machine. Crankshafts may be built up in sections or forged as a single component. In an engine, the reciprocating motion of the pistons transmits power to the crankshaft and causes it to rotate, whereas in a pump the crankshaft is driven and its rotation causes the pistons to reciprocate.
曲柄是往复式单缸或多缸机器主轴的一部分。曲轴可以分段组装或作为单个部件锻造。在发动机中,活塞的往复运动将动力传递给曲轴并使其旋转,而在泵中,曲轴被驱动,其旋转使活塞往复运动。
Radial marks 径向标记 Lines on a fracture surface that radiate from the fracture origin and are visible to the unaided eye or at low magnification. Radial lines result from the intersection and connection of brittle fractures propagating at different levels. Also known as shear ledges.
断裂表面上的线,从断裂起点辐射,肉眼可见或在低放大率下可见。径向线是在不同层面上传播的脆性断裂相交和连接的结果。也称为剪切壁架。
Selective heating 局部加热 Intentionally heating only certain portions of a workpiece.
有意仅加热工件的某些部分。
Thread rolling 滚丝 Thread rolling (also known as roll threading) is a cold forming process for producing threads or other helical or annular forms by rolling the impression of hardened steel dies into the surface of a cylindrical or conical blank. Polygonal blanks are also thread rolled for the purpose of fabricating thread-forming and self-locking screws. The preferred polygonal shape is trilobular and is produced in flat die machines.
螺纹滚压(也称为滚压螺纹)是一种冷成型工艺,通过将硬化钢模具的压痕滚压到圆柱形或锥形坯料的表面来生产螺纹或其他螺旋或环形形状。多边形坯料也进行螺纹轧制,以制造螺纹成型和自锁螺钉。优选的多边形形状为三棱形,并在平模机中生产。
Fatigue limit for p % survival p%存活率的疲劳极限 The limiting value of fatigue strength for p%survival as the number of stress cycles becomes very large; pmay be any number, such as 95, 90, etc.
随着应力循环次数的增加,p%存活率的疲劳强度极限值变得非常大;p可以是任何数字,例如95、90等。
Vibration-testing machine (vibrator) 振动试验机(振动器) Any machine that subjects components or systems to vibration at known amplitudes and frequencies in order to determine the response. vibratory equipment Vibrating process equipment, such as shakers, used to separate small and large particles, or feeders to supply particulate or granular material that may otherwise clog.
使部件或系统以已知振幅和频率振动以确定响应的任何机器。振动设备振动工艺设备,如用于分离小颗粒和大颗粒的振动筛,或用于供应可能堵塞的颗粒或粒状材料的给料机。
Engineering strain (e) 工程应变(e) A term sometimes used for average linear strain or conventional strain in order to differentiate it from true strain. In tension testing it is calculated by dividing the change in the gage length by the original gage length.
一个术语,有时用于平均线性应变或常规应变,以便将其与真实应变区分开来。在张力测试中,通过将标距变化除以原始标距来计算。
Damage mechanics 损伤机制 The theory of degradation in bodies, particularly fracture by accumulated microstructural damage. Analyses take two approaches: (a) the use of some critical integrated function of stress and strain at which cracking is initiated and propagated; (b) incorporation of damage in the stress–strain curves to reflect weakened material.
物体退化理论,尤其是累积微观结构损伤导致的断裂。分析采用两种方法:(a)使用裂纹开始和扩展时的应力和应变的一些临界积分函数;(b)应力-应变曲线中包含损伤,以反映弱化材料。
Density 密度 The mass per unit volume of a solid material. (mass density, ρ) (Unit kg/m³) The mass per unit volume of a substance that satisfies the continuum assumption. The reciprocal of specific volume.
固体材料每单位体积的质量。(质量密度,ρ)(单位kg/m³)满足连续统假设的物质每单位体积的质量。和比容相关联。
Thermal shock 热冲击 The development of a steep temperature gradient and accompanying high stresses within a structure.
在结构内形成陡峭的温度梯度和伴随的高应力。
Vernier 游标 A short auxiliary scale that slides along the main instrument scale to permit more accurate fractional reading of the least main division of the main scale.
一种短辅助刻度,沿主仪表刻度滑动,以便更准确地读取主刻度的最小主刻度。
Selective quenching 局部淬火 Quenching only certain portions of an object.
仅淬火工件的某些部分。
Fracture toughness 断裂韧性 A generic term for measures of resistance to extension of a crack. The term is sometimes restricted to results of fracture mechanics tests, which are directly applicable in fracture control. However, the term commonly includes results from simple tests of notched or precracked specimens not based on fracture mechanics analysis. Results from tests of the latter type are often useful for fracture control, based on either service experience or empirical correlations with fracture mechanics tests.
裂纹扩展阻力测量的通用术语。该术语有时仅限于断裂力学试验的结果,这些结果直接适用于断裂控制。该术语通常包括非基于断裂力学分析的切口或预裂纹试样的简单试验结果。基于使用经验或与断裂力学试验的经验相关性,后一类试验的结果通常有助于断裂控制。
Significance level 显着性水平 The stated probability (risk) that a given test of significance will reject the hypothesis that a specified effect is absent when the hypothesis is true.
当假设为真时,给定的显著性检验将拒绝特定效应不存在的假设的所述概率(风险)。
Actual power 实际功率 (actual horsepower) (Unit W or hp) The power delivered at the output shaft of an engine, before subsequent transmission through a gearbox etc.
(实际马力)(单位W或hp)在随后通过变速箱等传输之前,在发动机输出轴上传递的功率。
Turn-of-nut method 螺母转动法 It applies preload by turning a nut through an angle that corresponds to a given elongation.
它通过将螺母旋转一个与给定伸长率相对应的角度来施加预载荷。
Mechanical efficiency (η) 机械效率(η) 1. In general for a machine, the ratio of output work to input work. 2. For a compressor, the ratio of indicated power to shaft power; for a reciprocating engine or an expander, the ratio of shaft power to indicated power.
1.一般而言,机器的输出功与输入功之比。2.对于压缩机,指示功率与轴功率之比;对于往复式发动机或膨胀机,轴功率与指示功率之比。
Batch furnace 间歇式炉 A furnace used to heat treat a single load at a time. Batch-type furnaces are necessary for large parts such as heavy forgings and are preferred for complex alloy grades requiring long cycles.
用于一次热处理单个负载的炉子。对于重型锻件等大型零件,间歇式炉是必需的,对于需要长周期的复杂合金牌号来说是首选。
Shoulder joint 轴肩关节 The second joint on an articulated robot, which has a horizontal axis and is analogous to the human shoulder.
关节机器人上的第二个关节,具有水平轴,类似于人的肩膀。
Water hammer 水锤 The reflected pressure surge that occurs in a liquid flowing through a pipe, usually as a consequence of sudden closure of a valve. The surge may cause the pipe to vibrate and a hammering noise to be heard. Key factors affecting the surge amplitude are the compressibility of the liquid (especially if it contains undissolved gas) and the elasticity of the pipe wall.
在流经管道的液体中发生的反射压力波动,通常是阀门突然关闭的结果。浪涌可能导致管道振动,并听到锤击噪音。影响喘振幅度的关键因素是液体的可压缩性(特别是当其含有未溶解气体时)和管壁的弹性。
Turbulent flow (turbulence) 湍流 Fluid motion characterized by disorderly, rotational (i.e. vortical) three-dimensional velocity fluctuations covering a wide range of frequency and length scales. The pressure, temperature, and other fluid properties also fluctuate and the diffusion of heat, mass, and momentum is greatly enhanced. As are laminar and transitional flow, turbulent flow of a Newtonian fluid is governed by the Navier–Stokes equations which can in principle be solved by direct numerical simulation (DNS) in which all time and length scales of the fluctuating motion are resolved.
流体运动的特点是无序、旋转(即旋涡)三维速度波动,覆盖广泛的频率和长度尺度。压力、温度和其他流体特性也会波动,热、质量和动量的扩散会大大增强。与层流和过渡流一样,牛顿流体的湍流由Navier-Stokes方程控制,该方程原则上可以通过直接数值模拟(DNS)求解,在直接数值模拟中,波动运动的所有时间和长度尺度都可以求解。
Compression ratio 压缩率 The volume of a combustion chamber with the piston at the top of its stroke as a proportion of the total volume of the cylinder with the piston at the bottom of its stroke. For a piston engine, if the swept volume is SW and the clearance volume is CL, the compression ratio is given by ( SW + CL)/CL, i.e. it is a volume ratio rather than a pressure ratio.
活塞位于其冲程顶部的燃烧室的容积与活塞位于其冲程底部的气缸总体积的比例。对于活塞发动机,如果扫气量为SW,间隙容积为CL,则压缩比由(SW+CL)/CL给出,即它是体积比而不是压力比。
Combined stresses 复合应力 The stress state at a point in a component subjected to combination of axial, bending, torsional loadings etc., acting along all reference axes.
沿所有参考轴作用的受轴向、弯曲、扭转载荷等组合作用的部件中某点的应力状态。
Newton’s law of gravitation 牛顿万有引力定律 (Newton’s law of universal gravitation) Any two bodies exert a gravitational force of attraction F on each other directed along the line joining their centres of mass, in magnitude proportional to the product of their masses and inversely proportional to the square of the distance r between them.
(牛顿万有引力定律)任何两个物体沿其质心连接线相互施加引力F,其大小与其质量乘积成正比,与它们之间距离r的平方成反比。
Expansion bolt 膨胀螺栓 When a through bolt cannot be used for attaching a pipe hanger, bracket, or other part, to a wall or ceiling of brick or concrete, what are known as expansion bolts are often used. The body of an expansion bolt is divided and the arrangement is such that, when the head of the bolt is turned, the sections forming the body of the bolt are forced outward and against the wall of the hole which has been drilled into the brick, concrete, or stone, as the case may be. Bolts of this type are made in quite a variety of designs. The nominal size represents the diameter of the bolt proper and not the diameter of the casing or expansion member.
当不能使用贯穿螺栓将管道吊架、支架或其他部件连接到砖块或混凝土的墙壁或天花板时,通常使用所谓的膨胀螺栓。膨胀螺栓的主体是分开的,其布置方式是,当螺栓头转动时,形成螺栓主体的部分被强制向外并靠在已钻入砖、混凝土或石头中的孔壁上,视情况而定。这种类型的螺栓有多种设计。标称尺寸代表螺栓本身的直径,而不是套管或膨胀构件的直径。
Spinner 旋转器 A co-axial streamlined fairing enclosing the hub of a propeller and rotating with it.
一种同轴流线型整流罩,包围螺旋桨毂并随其旋转。
Quench cracking 淬火开裂 Fracture of a metal during quenching from elevated temperature. Most frequently observed in hardened carbon steel, alloy steel, or tool steel parts of high hardness and low toughness. Cracks often emanate from fillets, holes, corners, or other stress raisers and result from high stresses due to the volume changes accompanying transformation to martensite.
高温淬火时金属断裂。在高硬度和低韧性的硬化碳钢、合金钢或工具钢零件中最常见。裂纹通常来自圆角、孔、角部或其他应力集中区,并由伴随马氏体转变的体积变化引起的高应力引起。
Ideal critical diameter 理想临界直径 (DI). Under an ideal quench condition, the bar diameter that has 50% martensite at the center of the bar when the surface is cooled at an infinitely rapid rate (that is, when H = ∞, where H is the quench severity factor).
(DI)在理想淬火条件下,当表面以无限快的速度冷却时(即H=∞, 其中H是淬火严重度因子)。
Breaking stress 断裂应力 The stress at failure. Also known as rupture stress.
失效时的应力。也称为破裂应力。
Transformation toughening 相变增韧 The improvement of fracture toughness of a material by stress-induced transformation of the microstructure.
通过微结构的应力诱导转变来提高材料的断裂韧性。
Hypereutectic alloy 过共晶合金 In an alloy system exhibiting a eutectic, any alloy whose composition has an excess of alloying element compared with the eutectic composition, and whose equilibrium microstructure contains some eutectic structure.
在呈现共晶的合金系统中,任何合金,其组成与共晶组成相比具有过量的合金元素,并且其平衡微观结构包含一些共晶结构。
Wind velocity (Unit m/s) 风速(单位:m/s) 1. In the Earth’s atmosphere, a vector quantity that quantifies both the magnitude of the wind speed and its direction at a given altitude and location, conveniently represented in the hodograph plane. For convenience, the unit kph is often used. It could in principle also include information about large- and small-scale unsteadiness. Spatial variation in wind velocity, either with altitude or in a horizontal plane, is termed wind shear. 2. The airspeed in the working section of a wind tunnel.
1.在地球大气层中,一种矢量量,用于量化给定高度和位置处的风速大小及其方向,方便地用速度计平面表示。为方便起见,通常使用单位kph。原则上,它还可以包括关于大尺度和小尺度不稳定性的信息。风速随高度或水平面的空间变化称为风切变。2.风洞工作段的空速。
O-ring (O-ring seal) O形圈(O形密封圈) A toroidal ring of synthetic rubber seated in a groove machined into a flat or cylindrical surface to act as a seal.
一种环形合成橡胶环,位于加工成平面或圆柱表面的凹槽中,起密封作用。
Coefficient of rolling friction 滚动摩擦系数 The ratio of force parallel to a surface, on which an object rolls, to the normal force. Unlike sliding friction, rolling friction depends on the size of the contact patch and the radius of the rolling element, and the behaviour depends on whether the contact is elastic, viscoelastic, or plastic and on hysteresis losses.
平行于物体滚动表面的力与法向力之比。与滑动摩擦不同,滚动摩擦取决于接触片的大小和滚动元件的半径,其行为取决于接触是弹性的、粘弹性的还是塑性的以及滞后损失。
Thermodynamics laws 热力学定律 The zeroth, first, second, and third laws of thermodynamics.
热力学第零、第一、第二和第三定律。
Metallurgy 冶金 The study of the atomic, crystallographic, microstructural, mechanical, and physical properties of metallic elements and alloys and their applications.
研究金属元素和合金的原子、晶体学、微观结构、机械和物理特性及其应用。
Angularity 角度 The underfaces of the nut and the bolt head should be exactly perpendicular to the thread or shank axes. If the angle between the face and the axis is, for example, 868 or 948, the fastener is said to have an angularity of 48 (sometimes called Perpendicularity).
螺母和螺栓头的底面应与螺纹或柄轴完全垂直。例如,如果面和轴之间的角度为868或948,则称紧固件的角度为48(有时称为垂直度)。
Preload 预载 The tension created in a threaded fastener when the nut is first tightened. Often used interchangeably, but incorrectly, with Working load or bolt force or bolt tension
第一次拧紧螺母时螺纹紧固件中产生的张力。经常与工作载荷或螺栓力或螺栓张力互换使用但容易使用不当。
Heat (q, Q) (Unit J) 热量(q, Q)(单位J) A form of energy that is transferred across the boundary of a system at one temperature to another system (or the surroundings) at a different temperature by virtue of the temperature difference between them. Heat can be identified only as it crosses the boundary. A body can never be said to contain heat which is thus a transient phenomenon.
一种能量形式,由于它们之间的温差在一个温度下通过系统边界传递到另一个温度不同的系统(或环境)。只有当热量穿过边界时才能识别。一个物体不能说永远含有热量,这是一种瞬态现象。
Plastic deformation 塑性变形 The permanent (inelastic) distortion of a material under applied stress that strains the material beyond its elastic limit.
材料在施加应力下的永久(非弹性)变形,使材料应变超过其弹性极限。
Age hardening 时效硬化 Raising the strength and hardness of an alloy by heating a supersaturated solid solution at a relatively low temperature to induce precipitation of a finely dispersed second phase. Also known as aging or precipitation hardening. Hardening by aging, usually after rapid cooling or cold working.
通过在相对较低的温度下加热过饱和固溶体以诱导细分散的第二相沉淀来提高合金的强度和硬度。也称为时效或沉淀硬化。通常在快速冷却或冷加工后。
Thermoelectric junction 热电结 A welded, soldered, or twisted connection between the ends of two wires of dissimilar metals, as in a thermocouple.
两根不同金属线的末端之间的焊接、锡焊或绞合连接,如热电偶。
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