首页 专业字典
专业字典
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
词或词组 中文 英文解释中文解释
Critical strain 临界应变 The strain just sufficient to cause recrystallization; because the strain is small, usually only a few percent, recrystallization takes place from only a few nuclei, which produces a recrystallized structure consisting of very large grains.
刚好足以引起再结晶的应变;由于应变很小,通常只有百分之几,再结晶只发生在少数核上,从而产生由非常大的晶粒组成的再结晶结构。
Flame hardening 火焰硬化 A process for hardening the surfaces of hardenable ferrous alloys in which an intense flame is used to heat the surface layers above the upper transformation temperature, whereupon the workpiece is immediately quenched.
一种用于硬化可硬化铁合金表面的工艺,其中使用强烈的火焰将表面层加热到转变温度上限以上,然后立即对工件进行淬火。
Vibrometer 测振仪 A device used to measure the motion of a vibrating surface, typically using a contactless laser-based technique.
一种用于测量振动表面运动的装置,通常使用非接触激光技术。
Workspace (Unit m³) 工作空间(单位m³) (working-space volume) The volume around the base frame of a robot, defined by the reach of the robot. The robot can thus only perform tasks within this volume.
(工作空间体积)机器人基架周围的体积,由机器人的可达范围定义。因此,机器人只能执行该体积内的任务。
Elastic interactions 弹性相互作用 When a bolt is tightened it partially compresses the joint members ‘‘in its own neighborhood.’’ When nearby bolts are tightened later, they further compress the joint in this region. This allows the first bolt to relax a little (lose a little preload). Tightening bolts on the opposite side of the joint, however, might increase preload in some of the earlier bolts tightened on the near side. These shifts and changes in the elastic energy stored in individual bolts, during assembly, are called elastic interactions.
当螺栓拧紧时,它会“在其自身附近”部分压缩接头构件稍后拧紧附近的螺栓时,进一步压缩该区域的接头。这允许第一个螺栓稍微松弛(失去一点预载)。但拧紧接头另一侧的螺栓可能会增加早期在近侧拧紧的一些螺栓的预载。在装配过程中,储存在单个螺栓中的弹性能量的这些位移和变化称为弹性相互作用。
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。
Torque multiplier 扭矩放大器 A gearbox used to multiply the torque produced by a small hand wrench (usually a Torque wrench). The output of the multiplier drives the nut or bolt with a torque that is higher, and a speed that is lower, than input torque and speed. There is no torque gage or readout on the multiplier.
一种齿轮箱,用于增加小手动扳手(通常是扭矩扳手)产生的扭矩。倍增器的输出以比输入扭矩和速度更高的扭矩和更低的速度驱动螺母或螺栓。倍增器上没有扭矩计或读数。
Vice 老虎钳 A workshop tool used to hold a workpiece and consisting of two jaws, one fixed and the other moved by turning a screw.
一种用于夹持工件的车间工具,由两个钳口组成,一个固定,另一个通过转动螺钉移动。
Working fluid 工作流体 In thermodynamics, the fluid contained within the boundary of a system that experiences changes in its properties during any fluid dynamic or thermodynamic process.
在热力学中,包含在系统边界内的流体,在任何流体动力学或热力学过程中其性质发生变化。
Atomic volume 原子体积 Volume of unit cell per atom.
每个原子的晶胞体积。
Two-stage compressor 两级压缩机 A machine in which gas is compressed from low pressure toan intermediate pressure in a low-pressure cylinder, and then to final pressure in a highpressure cylinder. Efficiency is improved if the two cylinders are separated by an intercooler.
一种机器,其中气体在低压气缸中从低压压缩到中压,然后在高压气缸中压缩到最终压力。如果两个气缸由中冷器分离,则效率提高。
Water quenching 水淬 A quench in which water is the quenching medium. The major disadvantage of water quenching is its poor efficiency at the beginning or hot stage of the quenching process.
以水为淬火介质的淬火。水淬的主要缺点是在淬火过程的开始或热阶段效率低。
Slip band 滑带 A group of parallel slip lines so closely spaced as to appear as a single line when observed under an optical microscope.
一组平行滑移线,间距如此之近,以至于在光学显微镜下观察时显示为一条直线。
Power 力能 The rate of doing work or of producing or consuming energy. The unit of power is the watt, W, where 1 W = 1 N m/s.
做功或产生或消耗能量的速度。功率单位为瓦特,W,其中1W=1N m/s。
Standard 标准 (standard specification) A set of specifications for components, machines, materials, or processes intended to achieve uniformity, efficiency, and a specified quality. In the UK, standards issued by the British Standards Institution (BSI) are now generally those of the International Organization for Standardization (ISO).
(标准规范)为实现一致性、效率和特定质量而制定的一套组件、机器、材料或工艺规范。在英国,英国标准协会(BSI)发布的标准现在基本上是国际标准化组织(ISO)的标准。
Total energy (Unit J) 总能量(单位J) The sum of all forms of energy associated with a system, including kinetic, potential, internal, magnetic, chemical, and electrical energy.
与系统相关的所有形式能量的总和,包括动能、势能、内能、磁能、化学能和电能。
Cathode 阴极 That electrode in a battery or corrosion cell which attracts electrons.
电池或腐蚀电池中吸引电子的电极。
Grain 晶粒 1. An individual crystal in a polycrystalline solid. Most engineering materials such as metals and ceramics are used in polycrystalline form. 2. (gr) A non-SI unit of mass. The conversion to SI is 1 gr = 6.479 891 × 10−5 kg.
1.多晶固体中的单个晶体。大多数工程材料,如金属和陶瓷,都以多晶形式使用。2.(gr)非国际单位制的质量单位。转换为SI为1gr=6.479891×10-5kg。
Ferrite 铁素体 A solid solution of one or more elements in body-centered cubic iron. Unless otherwise designated (for instance, as chromium ferrite), the solute is generally assumed to be carbon. On some equilibrium diagrams, there are two ferrite regions separated by an austenite area. The lower area is alpha ferrite; the upper, delta ferrite. If there is no designation, alpha ferrite is assumed.
一种或多种元素在体心立方铁中的固溶体。除非另有说明(例如,铁酸铬),否则通常假定溶质为碳。在一些平衡图上,有两个铁素体区域被一个奥氏体区域隔开。下部区域为α铁素体;上部,δ铁氧体。如果没有指定,则假定为 α 铁氧体。
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。
Congruent melting point (Unit K) 全等熔点(单位K) congruent melting point (Unit K) The temperature at which a solid substance at a specified pressure changes phase to a liquid of identical composition.
一致的熔点(单位K)固体物质在特定压力下相变为具有相同成分的液体时的温度。
Thread form 螺纹形式 The cross-sectional shape of the threads, defining thread angle, root, and crest profiles, etc. Thread length Length of that portion of the fastener which contains threads cut or rolled to full depth.
螺纹的横截面形状,定义螺纹角度、齿根和齿冠轮廓等。螺纹长度:紧固件中包含全深度切割或轧制螺纹的部分的长度。
Two-phase flow 两相流 A flow in which two phases are present, for example gas bubbles in a liquid, liquid bubbles in another liquid with which it is immiscible, solid particles in a liquid or gas.
两相流动,例如液体中的气泡、与之不混溶的另一种液体中的液体气泡、液体或气体中的固体颗粒。
Pressure tap 测压口 A small hole in the wall of a pipe or pressure vessel to which is attached a tube, the other end of which is connected to one side of a pressure transducer.
管子或压力容器壁上的小孔,与管子相连,管子的另一端与压力传感器的一侧相连。
Physical testing 物理测试 Methods used to determine the entire range of physical properties of a material. In addition to density and thermal, electrical, and magnetic properties, physical testing methods can be used to assess simple fundamental physical properties such as color, crystalline form, and melting point.
用于确定材料整个物理特性范围的方法。除了密度和热、电、磁特性外,物理测试方法还可用于评估简单的基本物理特性,如颜色、结晶形式和熔点。
Stress cycle 应力循环 The smallest segment of the stress-time function that is repeated periodically.
周期性重复的应力时间函数的最小段。
Ventilation 通风系统 A system for circulating fresh air in a room, building, passenger vehicle, orother enclosed space.
在房间、建筑物、乘用车或其他封闭空间中循环新鲜空气的系统。
Hardening 硬化 Increasing hardness by suitable treatment, usually involving heating and cooling. When applicable, the following more specific terms should be used: age hardening, flame hardening, induction hardening, laser hardening, precipitation hardening, and quench hardening.
通过适当的处理增加硬度,通常包括加热和冷却。适用时,应使用以下更具体的术语:时效硬化、火焰硬化、感应硬化、激光硬化、沉淀硬化和淬火硬化。
Temper embrittlement 回火脆化 Brittleness that results when certain steels are held within, or are cooled slowly through, a certain range of temperature below the transformation range. The brittleness is manifested as an upward shift in ductile-to-brittle transition temperature but only rarely produces a low value of reduction in area in a smooth-bar tension test of the embrittled material. The anomalous reduction in toughness of martensitic stainless steels when tempered in the range 370–600°C. Embrittlement of alloy steels caused by holding within or cooling slowly through a temperature range just below the transformation range. Embrittlement is the result of the segregation at grain boundaries of impurities such as arsenic, antimony, phosphorus, and tin; it is usually manifested as an upward shift in ductile-to-brittle transition temperature. Temper embrittlement can be reversed by retempering above the critical temperature range, then cooling rapidly.
当某些钢保持在低于转变范围的某一温度范围内或缓慢冷却时产生的脆性。脆性表现为延性到脆性转变温度的向上移动,但在脆性材料的平滑棒材拉伸试验中,很少产生较小的面积减小值。马氏体不锈钢在370–600°C范围内回火时的韧性异常降低。合金钢的脆化是由于在低于转变范围的温度范围内保持或缓慢冷却而引起的。脆化是杂质(如砷、锑、磷和锡)在晶界处偏析的结果;它通常表现为韧脆转变温度的上升。回火脆化可以通过在临界温度范围以上重新回火,然后快速冷却来逆转。
Computer control 电脑控制 The control of an engineering device or system by pre-programmed computer or by feedback control.
通过预编程计算机或反馈控制对工程设备或系统进行控制。
Compressometer 压力计 Instrument for measuring change in length over a given gage length caused by application or removal of a force. Commonly used in compression testing of metal specimens.
用于测量在给定标距上由施加或移除力引起的长度变化的仪器。常用于金属试样的压缩试验。
Granular fracture 粒状断裂 A type of irregular surface produced when metal is broken that is characterized by a rough, grainlike appearance, rather than a smooth or fibrous one. It can be subclassified as transgranular or intergranular.
金属破碎时产生的一种不规则表面,其特征是粗糙的颗粒状外观,而不是光滑或纤维状的外观。它可以细分为穿晶或晶间。
Mean diameter (Unit m) 平均直径(单位米) The average of the inside and outside diameters for a helical spring or hollow circular cylinder or sphere
螺旋弹簧或空心圆柱体或球体的内径和外径的平均值
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。
Screw thread 螺纹 A ridge of uniform section or shape in the form of a helix on the external or internal surface of a cylinder, or in the form of a conical spiral on the external or internal surface of a cone.
在圆柱体的外表面或内表面上呈螺旋形或在圆锥体的外表面和内表面上以锥形螺旋形的均匀截面或形状的脊。
Yield stress 屈服应力 The stress level of highly ductile materials, such as structural steels, at which large strains take place without further increase in stress.
高韧性材料(如结构钢)的应力水平,在该应力水平下发生大应变而不会进一步增加。
Dead centre 止点 The point at which, in a crank mechanism, the piston connecting rod and crank are all in line so that there can be no driving moment.
在曲柄机构中,活塞连杆和曲柄都在一条线上,因此不会有驱动力矩。
Bolt blank 螺栓毛坯 A rod on which a head has been formed, but on which no thread has been cut, from which bolts or screws may be made as required.
一种已形成头部但未切割螺纹的杆,可根据需要从中制造螺栓或螺钉。
Fastener 紧固件 A fastener is a mechanical device for holding two or more bodies in definite positions with respect to each other.
紧固件是一种机械装置,用于将两个或多个物体相对于彼此固定在确定的位置。
Fatigue life (N) 疲劳寿命(N) The number of cycles of stress or strain of a specified character that a given specimen sustains before failure occurs.
给定试样在失效发生之前所承受的特定特征的应力或应变的循环次数。
Adhesive wear 粘着磨损 Wear that develops when two surfaces slide across one another under pressure. The removal or displacement of material from a surface by the welding together and subsequent shearing of minute areas of two surfaces that slide across each other under pressure. In advanced stages, may lead to galling. Contrast with abrasive wear.
当两个表面在压力下相互滑动时产生的磨损。通过焊接在一起并随后剪切在压力下相互滑动的两个表面的微小区域,从表面去除或置换材料。在晚期,可能会导致擦伤。与磨料磨损形成对比。
Friction 摩擦 The resistance that a body encounters when sliding over another body, or experiences when a viscous fluid flows over its surface.
一个物体在另一个物体上滑动时遇到的阻力,或者当粘性流体流过其表面时所经历的阻力。
Coarsening 粗粒化 An increase in the grain size, usually, but not necessarily, by grain growth.
晶粒尺寸的增加,通常但不一定是晶粒变大。
Full annealing 全退火 An imprecise term that denotes an annealing cycle to produce minimum strength and hardness. For the term to be meaningful, the composition and starting condition of the material and the time-temperature cycle used must be stated. Annealing a ferrous alloy by austenitizing and then cooling slowly through the transformation range.
一个不精确的术语,表示产生最小强度和硬度的退火循环。为了使该术语有意义,必须说明材料的组成和起始条件以及使用的时间-温度循环。通过奥氏体化退火铁合金,然后在转变范围内缓慢冷却。
Junker machine 容克机 A test machine, first proposed by Gerhard Junker, for testing the vibration resistance of fasteners.
由Gerhard Junker首次提出的测试机,用于测试紧固件的抗振性。
Turbine pump (turbopump) 涡轮泵 An axial or centrifugal pump driven by a turbine. Typically used to supply fuel to the combustion chamber of a rocket engine such as on the space shuttle.
由涡轮驱动的轴向或离心泵。通常用于向火箭发动机(如航天飞机)的燃烧室供应燃料。
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。
Resistance thermometer 电阻温度计 A thermometer in which the sensing element is basically a metal wire, usually of platinum, for which the variation of resistance with temperature is known accurately. A resistance pyrometer is a resistance thermometer intended for use up to about 1 000°C.
一种温度计,其中传感元件基本上是一根金属线,通常是铂,可以准确地知道电阻随温度的变化。电阻高温计是一种电阻温度计,用于高达约1000°C的温度。
Tear strength (Unit N/m) 撕裂强度(单位:N/m) The tensile force divided by the sheet thickness required to tear a pre-split sheet material at a specified rate. Particularly used for plastics, rubber, fabrics, and elastomers. Since the units are not those of stress but equivalent to J/m², the units of toughness, the term ‘strength’ is strictly incorrect.
按规定速率撕裂预裂片材所需的张力除以片材厚度。特别用于塑料、橡胶、织物和弹性体。由于单位不是应力单位,而是相当于J/m²,韧性单位,“强度”一词是完全错误的。
Coefficient of thermal expansion 热膨胀系数 (1) Change in unit of length (or volume) accompanying a unit change of temperature, at a specified temperature. (2) The linear or volume expansion of a given material per degree rise of temperature, expressed at an arbitrary base temperature or as a more complicated equation applicable to a wide range.
(1) 单位长度(或体积)随温度单位变化的变化。(2) 给定材料每上升一度的线性或体积膨胀,在任意基础温度下表示,或作为适用于宽范围的更复杂方程表示。
Blueing 发蓝 Application of blue dye (‘engineers’ blue’) to identify high spots on surfaces in contact, or for marking out.
应用蓝色染料(“工程师蓝”)来识别接触表面上的高点,或用于标记。
Sigma phase σ相 A hard, brittle, nonmagnetic intermediate phase with a tetragonal crystal structure, containing 30 atoms per unit cell, space group P42/mnm, occurring in many binary and ternary alloys of the transition elements. The composition of this phase in the various systems is not the same, and the phase usually exhibits a wide range in homogeneity. Alloying with a third transition element usually enlarges the field of homogeneity and extends it deep into the ternary section.
一种硬、脆、非磁性中间相,具有四方晶体结构,每单位晶胞含有30个原子,空间群P42/mnm,存在于许多过渡元素的二元和三元合金中。该相在各种系统中的组成不尽相同,并且该相通常表现出宽范围的均匀性。与第三过渡元素的合金化通常会扩大均匀性范围,并将其延伸到三元区。
Wind pump 风泵 A pump driven directly by a windmill on a tower. Widely used in remote locations.
由塔上的风车直接驱动的泵。广泛应用于偏远地区。
Computer vision 计算机视觉 The digitization and processing of optical images/patterns by computer in order to recognize parts, orientation, etc. in manufacturing.
通过计算机对光学图像/图案进行数字化和处理,以在制造过程中识别零件、方向等。
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。
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。
Micrometer 千分尺 (micrometer gauge) A mechanical-contact device for the accurate measurement of the length, width, diameter, etc. of an object, the depth of a hole, the height of a step, etc. The usual arrangement is a spindle that is moved by rotation of a thimble, the distance then being read off a vernier scale.
(千分尺)一种机械接触装置,用于精确测量物体的长度、宽度、直径等、孔的深度、台阶的高度等。通常的布置是通过顶针的旋转移动主轴,然后通过游标尺读取距离。
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。
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。
Critical temperature ranges 临界温度范围 Synonymous with transformation ranges, which is the preferred term.
与转换范围同义,这是首选术语。
Hydrogen damage 氢损伤 A general term for the embrittlement, cracking, blistering, and hydride formation that can occur when hydrogen is present in some metals.
当氢存在于某些金属中时可能发生的脆化、开裂、起泡和氢化物形成的总称。
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。
Combustible 易燃 (inflammable) A term for substances that can be ignited and burned.
(易燃)可点燃和燃烧的物质的术语。
Proportional limit 比例极限 The greatest stress a material is capable of developing without a deviation from straight-line proportionality between stress and strain.
材料能够产生的最大应力不偏离应力和应变之间的直线比例。
Shrink fit 过盈配合 A tight interference fit between two components resulting from heating an outer part and/or cooling an inner part to allow easy assembly. The outer component contracts on cooling, while the inner part expands on warming to ambient temperature, thus gripping the two parts together.
由于加热外部部件和/或冷却内部部件而导致的两个部件之间的紧密过盈配合,以便于组装。外部部件在冷却时收缩,而内部部件在加热到环境温度时膨胀,从而将两个部件夹在一起。
Normalizing 正火 Heating a ferrous alloy to a suitable temperature above the transformation range and then cooling in air to a temperature substantially below the transformation range.
将铁合金加热至高于转变范围的合适温度,然后在空气中冷却至基本低于转变范围的温度。
Balancing machine 平衡机 A device that assesses the state of static and dynamic balance of a rotating part, and indicates the magnitude and location of weights to be added to give balance.
一种装置,用于评估旋转部件的静态和动态平衡状态,并指示为获得平衡而添加的砝码的大小和位置。
Bright annealing 光亮退火 Annealing in a protective medium to prevent discoloration of the bright surface.
在保护介质中退火以防止光亮表面变色。
Toggle (toggle clamp) 拨动(拨动夹) A device consisting of two pinned levers that are almost in line between two end points in the same plane. Bringing the levers into line generates large forces between the ends. Used to obtain a large mechanical advantage or as a locking mechanism.
由两个销杆组成的装置,在同一平面的两个端点之间几乎成一条直线。将杠杆对齐会在端部之间产生较大的力。用于获得较大的机械优势或用作锁定机构。
International System of Units 国际单位制 (SI system of units, Le Système international d’unités) The standard system of units now used almost universally in science and engineering except in the United States. The definitive reference on the SI is a booklet published by the International Bureau of Weights and Measures, often referred to as the BIPM SI Brochure. There are seven base units: metre (symbol m) for length; kilogram (kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux.  Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred.(kg) for mass; mole (mol) for amount of substance; second (s) for time; kelvin (K) for temperature; ampere (A) for electric current; and candela (cd) for luminous intensity. New SI unit definitions, based upon the values of the universal constants of nature (also termed the fundamental physical constants: the Avogadro constant, the Boltzmann constant, and the Planck constant), came into effect on 20 May 2019. Minor adjustments were also made to the values of these constants. In addition to the base units, there are 22 coherent derived units, including radian (rad) for plane angle, steradian (sr) for solid angle, hertz (Hz) for frequency, newton (N) for force, pascal (Pa) for pressure, joule (J) for energy, work, and amount of heat, and watt (W) for power and radiant flux.  Recommended practice is to avoid combinations such as N/mm², MN/m² being preferred.
(国际单位制,Le Système international d\\\'unités)目前美国除外,在科学和工程中几乎是普遍使用的标准单位制。SI的最终参考是国际度量衡局出版的小册子,通常称为BIPM SI小册子。有七个基本单位:米(符号m)表示长度;质量为千克(kg);物质量的摩尔(mol);时间为秒;开尔文(K)表示温度;电流为安培(A);而坎德拉(cd)表示发光强度。新的国际单位制定义于2019年5月20日生效,该定义基于自然界的普遍常数(也称为基本物理常数:阿伏伽德罗常数、玻尔兹曼常数和普朗克常数)。这些常数的值也进行了少量调整。除了基本单位外,还有22个相干导出单位,包括平面角的弧度(rad)、立体角的斯特拉迪安(sr)、频率的赫兹(Hz)、力的牛顿(N)、压力的帕斯卡(Pa)、能量、功和热量的焦耳(J)以及功率和辐射通量的瓦特(W)。建议的做法是避免N/mm²、MN/m²等组合。
Structural analysis 结构分析 The determination of the forces, displacements, stresses, and strains in a given structure.
确定给定结构中的力、位移、应力和应变。
Combined carbon 复合碳 The part of the total carbon in steel or cast iron that is present as other than free carbon.
钢或铸铁中总碳中除游离碳外的部分。
Thermodynamic pressure (Unit Pa) 热力学压力(单位Pa) The pressure within a fluid given by an equation of state such as p(ρ,T) where ρ is the fluid density and T is the absolute temperature of the fluid.
流体中的压力由状态方程给出,如p(ρ,T),其中ρ是流体密度,T是流体的绝对温度。
Pressure (p) (Unit Pa) 压力(p)(单位Pa) In thermodynamics and fluid mechanics, the compressive force exerted by the fluid per unit area. The pressure exerted by a fluid on a surface acts normal to the surface.
在热力学和流体力学中,每单位面积流体施加的压缩力。流体施加在表面上的压力垂直于表面。
Morse taper 莫氏锥度 A self holding, standard taper largely used on drilling tools, drilling machine spindles, and some lathes.
一种自持式标准锥度,主要用于钻孔工具、钻床主轴和一些车床。
Fastener specification 紧固件规格 A precise statement of set requirements to be satisfied by a fastener, its material, or its processing. It also indicates the procedure used to determine whether the requirements given are satisfied.
对紧固件、其材料或加工过程要满足的设定要求的精确陈述。它还指出了用于确定是否满足给定要求的程序。
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。
ASME ASME The American Society of Mechanical Engineers.
美国机械工程师学会。
Brittle lacquer coating 脆性漆涂层 A lacquer that, when painted on to an unloaded body, reveals the direction of maximum tension stresses from the pattern of cracking produced in the lacquer when the body is loaded.
一种漆,当涂在未加载的车身上时,从车身加载时在漆中产生的裂纹图案中显示出最大拉应力的方向。
Torque (T) (Unit N.m) 扭矩(T)(单位:N.m) The twisting moment, product of force and wrench length, applied to a nut or bolt (for example). The twisting moment of a force or couple about an axis which results in torsion.
施加在螺母或螺栓(例如)上的扭矩,是力和扳手长度的乘积。力或力偶绕轴产生扭转的力矩。
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
Design pressure (Unit Pa) 设计压力(单位Pa) The greatest pressure that a closed container is expected to experience under normal operating conditions.
密闭容器在正常操作条件下预期承受的最大压力。
Screw machine 螺丝机 A machine tool for high-volume manufacture of small turned components from rod or bar.
一种用棒或棒大批量制造小零件的机床。
Fastener with reduced shank 短柄紧固件 Finished fastener with a shank diameter of ds ≈ d2.
柄径为ds≈d2的紧固件。
Abrasive wear 磨料磨损 The removal or displacement of material from a surface when hard particles slide or roll across the surface under pressure. The particles may be loose or may be part of another surface in contact with the surface being worn. Contrast with adhesive wear.
当硬质颗粒在压力下在表面上滑动或滚动时,材料从表面上的去除或位移。颗粒可能是松散的或可能是与被磨损表面接触的另一个表面的一部分。与粘着磨损形成对比。
Structural frame 结构框架 The underlying load-bearing framework of beams, columns, bracing, etc., of steel, concrete, brick, stone, timber etc., required to support the static and dynamic forces a building or component is subjected to, including its weight and that of its contents.
由钢、混凝土、砖、石、木材等制成的梁、柱、支撑等构成的底层承重框架,用于支撑建筑物或构件承受的静态和动态力,包括其重量及其内含物的重量。
Ductile 延展性材料 (ductile material) Describes a material that can be deformed permanently to large strains without fracture. If a bolt can be stretched well past its yield point before breaking, it is said to be ductile.
(延展性材料)描述一种可以永久变形到大应变而不断裂的材料。如果螺栓在断裂前可以很好地拉伸超过其屈服点,则称其具有延展性。
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。
Stress amplitude 应力幅值 One-half the algebraic difference between the maximum and minimum stress in one cycle of a repetitively varying stress.
重复变化应力的一个循环中最大和最小应力之间代数差的一半。
Low-E coating 低辐射涂层 (low-emittance coating) A thin metallic or metal-oxide coating on a glass sheet to absorb and reflect infrared radiation. The coating is applied either by a pyrolytic chemical vapour-deposition process (hard coat), or by sputtering (soft coat).
(低辐射涂层)玻璃板上的薄金属或金属氧化物涂层,用于吸收和反射红外辐射。通过热解化学气相沉积工艺(硬涂层)或溅射(软涂层)施加涂层。
Absolute expansion 绝对扩张 The true volumetric expansion of a liquid with temperature, after account is taken of any expansion of the container in which it is held.
考虑到容纳液体的容器的任何膨胀后,液体随温度的真实体积膨胀。
Rolled thread 滚制螺纹 A thread formed by plastically deforming the surface of the blank rather than by cutting operations. Increases fatigue life and thread strength, but is not possible (or perhaps economical) on larger sizes.
通过塑性变形坯料表面而不是通过切割操作形成的螺纹。增加疲劳寿命和螺纹强度,但不太可能(或者说是经济上不太可能)用于较大的尺寸。
Deviation 偏差 The difference between the actual value and the desired value of a controlled variable.
受控变量的实际值与期望值之间的差值。
Lüders lines 吕德斯线 Elongated surface markings or depressions, often visible with the unaided eye, that form along the length of sheet metal or a tension specimen at an angle of approximately 45° to the loading axis. Caused by localized plastic deformation, they result from discontinuous (inhomogeneous) yielding. Also known as Lüders bands, Hartmann lines, Piobert lines, or stretcher strains.
拉长的表面标记或凹陷,通常肉眼可见,沿金属板或拉伸试样的长度形成,与加载轴的角度约为45°。由于局部塑性变形,它们是不连续(不均匀)屈服的结果。也被称为吕德斯带、哈特曼线、皮奥伯特线或拉伸线。
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。
Allotropy 同素异形体 A near synonym for polymorphism. Allotropy is generally restricted to describing polymorphic behavior in elements, terminal phases, and alloys whose behavior closely parallels that of the predominant constituent element.
多态性的近义词。同素异形体通常仅限于描述元素、终端相和合金中的多晶型行为,其行为与主要组成元素的行为非常相似。
Fastener manufacturer 紧固件制造商 An organization that fabricates raw steel into a fastener meeting specified standards.
将生钢加工成符合规定标准的紧固件的组织。
Tensiometer 张力计 An instrument used to measure surface tension.
用来测量表面张力的仪器。
ANSI ANSI The acronym for American National Standards Institute.
美国国家标准协会的缩写。
Electroplating 电镀 Deposition of one metal on to another using electrolysis. The metal to be plated forms the cathode in an electrolytic cell, and the metal to be deposited forms the anode.
使用电解将一种金属沉积到另一种金属上。待镀金属形成电解池中的阴极,待沉积金属形成阳极。
Grain growth 晶粒生长 An increase in the average size of the grains in polycrystalline metal, usually as a result of heating at elevated temperature.
多晶金属中晶粒平均尺寸的增加,通常是高温加热的结果。
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。
Weight (W) (Unit N) 重量(W)(单位:N) The force of attraction on a body due to gravity. A body’s weight is the product of its mass and the gravitational field strength at that point. Mass remains constant, but weight depends on the object’s position on the Earth’s surface, decreasing with increasing altitude. If g is the acceleration due to gravity, the weight of a mass m is given by W = mg. On Earth, the acceleration due to gravity is approximately 9.81 m/s², so that the weight of a 1 kg mass is 9.81 N. More generally, the weight is the force exerted on the mass of a body when in the gravitational field of another body.
重力由于重力作用在物体上的吸引力。物体的重量是其质量和该点引力场强度的乘积。质量保持不变,但重量取决于物体在地球表面的位置,随着海拔的升高而减小。如果g是重力引起的加速度,则质量m的重量由W=mg给出。在地球上,重力引起的加速度约为9.81m/s²,因此1千克质量的重量为9.81N。更一般地说,重量是在另一个物体的重力场中施加在物体质量上的力。
Rated flow (Unit m³/s or kg/s) 额定流量(单位:m³/s或kg/s) In a hydraulic system or machine, the volume or mass flow rate a manufacturer specifies for a component as the maximum desirable for it to function as designed.
在液压系统或机器中,制造商为部件指定的体积或质量流量是其按设计运行所需的最大值。
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。
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。
Fatigue wear 疲劳磨损 Wear of a solid surface caused by fracture arising from material fatigue.
由材料疲劳引起的断裂引起的固体表面磨损。
Fracture stress 断裂应力 The true normal stress on the minimum cross-sectional area at the beginning of fracture. This term usually applies to tension tests of unnotched specimens.
断裂开始时最小横截面积上的真实正应力。该术语通常适用于无缺口试样的拉伸试验。
Fluid mechanics 流体力学 The study of fluids in motion (fluid dynamics) or fluid statics where there is no relative motion between fluid particles. Fluid statics concerns primarily the variation of pressure with altitude or depth; it includes aerostatics and hydrostatics. Fluid dynamics includes the topics of aerodynamics, gas dynamics, hydraulics, hydrodynamics and many aspects of acoustics, chemical engineering, flight, lubrication, meteorology, non-Newtonian fluid flow, oceanography, power-plant technology, propulsion, and turbomachinery.
研究运动中的流体(流体动力学)或流体静力学,其中流体粒子之间没有相对运动。流体静力学主要关注压力随高度或深度的变化;它包括空气静力学和流体静力学。流体动力学包括空气动力学、气体动力学、水力学、流体动力学以及声学、化学工程、飞行、润滑、气象学、非牛顿流体流动、海洋学、发电厂技术、推进和涡轮机械的许多方面。
Yield point (Unit Pa) 屈服点(单位Pa) The first stress in a material, usually less than the maximum attainable stress, at which an increase in strain occurs without an increase in stress. Only certain metals—those which exhibit a localized, heterogeneous type of transition from elastic to plastic deformation—produce a yield point. If there is a decrease in stress after yielding, a distinction may be made between upper and lower yield points. The load at which a sudden drop in the flow curve occurs is called the upper yield point. The constant load shown on the flow curve is the lower yield point. (yield strength, yield stress, Rel, Rel) The stress at which the onset of permanent (plastic) deformation (yielding) occurs in a body under increasing loading. In some materials, a yield-point phenomenon occurs in which stress falls on initial yielding and plastic deformation continues without increase in stress as strain increases further. The yield criterion is the combination of normal and shear stresses which produces yielding under multiaxial loading.
材料中的第一应力,通常小于可达到的最大应力,在该应力下应变增加而应力不增加。只有某些金属——表现出从弹性变形到塑性变形的局部、非均匀类型的金属——才会产生屈服点。如果屈服后应力降低,可区分上屈服点和下屈服点。流量曲线突然下降时的荷载称为上屈服点。流量曲线上显示的恒定载荷为较低屈服点。(屈服强度,屈服应力,Rel)在不断增加的载荷下,物体发生永久(塑性)变形(屈服)时的应力。在某些材料中,会出现屈服点现象,即应力在初始屈服时下降,随着应变进一步增加,塑性变形继续,而应力没有增加。屈服准则是在多轴载荷下产生屈服的正应力和剪应力的组合。
Self-locking nut 自锁螺母 A nut with an inherent locking action which minimizes loosening due to vibration. A self-locking screw locks itself in place without the need for a separate selflocking nut or lock washer.
一种具有固有锁定作用的螺母,可将振动引起的松动降至最低。自锁螺钉将自身锁定到位,无需单独的自锁工件或锁紧垫圈。
Taper pins 圆锥销 A pin or peg of circular cross section that tapers along its length. Steel pins used for locating and holding the machine parts in position on a shaft.
沿其长度逐渐变细的圆形横截面的销钉或销钉。用于在轴上定位和固定机器零件的钢销。
Nanomaterial 纳米材料 A material defined by the European Commission as ‘A natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50% or more of the particles in the number size distribution, one or more external dimensions is in the size range 1–100 nm. In specific cases and where warranted by concerns for the environment, health, safety or competitiveness the number size distribution threshold of 50% may be replaced by a threshold between 1 and 50%.’
由欧盟委员会定义为“含有颗粒的天然、偶然或人造材料,处于未结合状态或聚集体或凝聚体,其中,对于数量-尺寸分布中的50%或更多颗粒,一个或多个外部尺寸在1-100nm的尺寸范围内”。在特定情况下,如果考虑到环境、健康、安全或竞争力,50%的数量大小分布阈值可以由1%到50%之间的阈值代替。
Carbonization 碳化 Conversion of an organic substance into elemental carbon.
将有机物质转化为元素碳。
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。
Durometer hardness 硬度计硬度 Measure of the indentation hardness of plastics. It is the extent to which a spring-loaded steel indenter protrudes beyond the pressure foot into the material.
塑料压痕硬度的测量。它是弹簧加载的钢压头超出压力脚伸入材料的程度。
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。
Mohr–Coulomb yield criterion Mohr–Coulomb屈服准则 A pressure-dependent yield criterion, according to which yielding occurs when the stress at a point in a material falls on the envelope created by the Mohr’s stress circles at yielding for various tests such as tension, shear, and compression that have different components of hydrostatic stress.
一种与压力相关的屈服准则,根据该准则,当材料中某一点的应力落在屈服时的莫尔应力圆所形成的包络线上时,即发生屈服,用于各种试验,如具有不同静水应力分量的拉伸、剪切和压缩。
Vertical engine 立式发动机 A piston engine having the cylinders above the crankshaft.
气缸位于曲轴上方的活塞发动机。
Transgranular fracture 穿晶断裂 Fracture in crystalline materials where the path of cracking is predominantly across grains.
晶体材料中的断裂,其中裂纹路径主要跨越晶粒。
Work ratio 工作比 The ratio of the net work out to the actual work out for a thermodynamic cycle.
热力学循环的净功与实际功之比。
Ratchet marks 棘轮痕 Lines on a fatigue fracture surface that result from the intersection and connection of fatigue fractures propagating from multiple origins. Ratchet marks are parallel to the overall direction of crack propagation and are visible to the unaided eye or at low magnification.
疲劳断裂面上由从多个源头传播的疲劳断裂的交叉和连接产生的线。棘轮标记与裂纹扩展的整个方向平行,肉眼或低倍镜下均可看到。
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。
Shear modulus (G) 剪切模量(G) The ratio of shear stress to the corresponding shear strain for shear stresses below the proportional limit of the material. Values of shear modulus are usually determined by torsion testing. Also known as modulus of rigidity.
对于低于材料比例极限的剪切应力,剪切应力与相应剪切应变之比。剪切模量值通常通过扭转试验确定。也称为刚度模量。
Austempering 等温淬火 A heat treatment for ferrous alloys in which a part is quenched from the austenitizing temperature at a rate fast enough to avoid formation of ferrite or pearlite and then held at a temperature just above Ms until transformation to bainite is complete. Although designated as bainite in both austempered steel and austempered ductile iron (ADI), austempered steel consists of two phase mixtures containing ferrite and carbide, while austempered ductile iron consists of two phase mixtures containing ferrite and austenite. Heat treatment comprising austenitization of a steel article, cooling it to a bainitic range at a rate higher than the critical cooling rate and holding at a fixed temperature until the completion of bainitic transformation.
一种铁合金的热处理,其中零件从奥氏体化温度以足够快的速度淬火,以避免形成铁素体或珠光体,然后保持在略高于Ms的温度,直到完全转变为贝氏体。虽然在奥氏体钢和奥氏体球铁(ADI)中都被指定为贝氏体,但奥氏体钢由含有铁素体和碳化物的两相混合物组成,而奥氏体球墨铸铁由含有铁素体和奥氏体的两相混合物组成。热处理包括钢制品的奥氏体化,以高于临界冷却速率的速率将其冷却到贝氏体范围,并保持在固定温度直到贝氏体转变完成。
Auxiliary power unit (APU) 辅助动力装置(APU) In aircraft–gas–turbine applications, a small gas turbine used to provide start-up power, electrical and hydraulic power, and compressed air for cabin ventilation. In other applications, an APU may be a gas turbine or internal-combustion engine used to provide emergency power.
在飞机-燃气轮机应用中,小型燃气轮机用于提供启动动力、电力和液压动力以及用于机舱通风的压缩空气。在其他应用中,APU可以是用于提供应急动力的燃气轮机或内燃机。
Eutectic melting 共晶熔化 Melting of localized microscopic areas whose composition corresponds to that of the eutectic in the system.
局部微观区域的熔化,其成分对应于系统中的共晶成分。
Tension 拉伸 The force or load that produces elongation. 1. The condition in a bar, belt, cable, spring, string, wire, etc. that is being pulled from either end. 2. (tensile force) (unit N) The force associated with tension as in (1). It is measured by a tension meter.
伸长力产生伸长的力或载荷。1.从两端拉出的杆、带、电缆、弹簧、线、线等的状态。2.(张力)(单位N)与张力相关的力。
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。
Air classifier 空气分级机 (air elutriator) A device in which an airstream, which may be swirling, sorts particles by a combination of size, shape, and mass.
(空气淘析器)一种装置,在该装置中,气流(可能是漩涡)根据大小、形状和质量的组合对颗粒进行分类。
Angle of torsion 扭转角 (angle of twist) (Unit ° or rad) The angle relative to a chosen section, normal to the axis of twist, through which another part of a component rotates when subjected to a torque.
(扭转角)(单位°或弧度)相对于选定截面的角度,垂直于扭转轴,部件的另一部分在受到扭矩时通过该角度旋转。
Flange 法兰 Flange refers to a head style for bolts where there is a circular ‘flange’ under the head that acts like a washer to distribute a load. A flange is a projected flat rim or collar. 1. Annular rims at the ends of pipes (flanged pipe) or shafts by which they may be coupled together using bolts that pass through holes in the flanges (flange coupling, flange union), or by toggle clamps around the periphery. 2. An extended rim on a wheel that positions it laterally on a track. Commonly used for railway rolling stock. 3. The top and bottom parts of an I-beam.
法兰是指螺栓的头部样式,其中头部下方有一个圆形“法兰”,其作用类似于垫圈以分配载荷。凸缘是凸出的平轮辋或凸缘。1.管道(法兰管)或轴端部的环形边缘,通过这些边缘,可以使用穿过法兰孔的螺栓(法兰联轴器、法兰接头)或通过周边的肘节夹将管道连接在一起。2.车轮上的延伸轮辋,将其横向定位在轨道上。通常用于铁路车辆。3.工字梁的顶部和底部。
Vapour static pressure 蒸汽静压 (Unit Pa or bar) A pressure analogous to hydrostatic pressure, where the fluid is a vapour such as steam. A term used in geothermal applications.
(单位Pa或bar)类似于静水压力的压力,其中流体是蒸汽,如蒸汽。地热应用中使用的术语。
Principal stress (normal) 主应力(正常) The maximum or minimum value of the normal stressat a point in a plane considered with respect to all possible orientations of the considered plane. On such principal planes the shear stress is zero. There are three principal stresses on three mutually perpendicular planes. The state of stress at a point may be: (1) uniaxial, a state of stress in which two of the three principal stresses are zero; (2) biaxial, a state of stress in which only one of the three principal stresses is zero; or (3) triaxial, a state of stress in which none of the principal stresses is zero. Multiaxial stress refers to either biaxial or triaxial stress.
相对于所考虑平面的所有可能方向,所考虑平面中某点处的法向应力的最大值或最小值。在这样的主平面上,剪切应力为零。在三个相互垂直的平面上有三个主应力。一点的应力状态可以是:(1)单轴,三个主应力中的两个为零的应力;(2)双轴,三个主应力中只有一个为零的应力状态;或(3)三轴,即主应力均不为零的应力状态。多轴应力是指双轴或三轴应力。
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。
Valve plug 阀塞 A conical or cylindrical plug, in which there are transverse holes, in a valve, such as a plug valve. Flow through the holes occurs when the plug is rotated.
阀门中的圆锥形或圆柱形阀塞,其中有横向孔,如旋塞阀。旋转阀塞时,会发生通过孔的流动
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。
Stress difference (Unit Pa) 应力差(单位Pa) The algebraic difference between the largest and least principal stresses in a loaded body, equal to twice the greatest shear stress in the system. For σ1 > σ2 > σ3, it is given by (σ1 − σ3).
载荷体中最大和最小主应力之间的代数差,等于系统中最大剪应力的两倍。由(σ1− σ3).,可得σ1>σ2>σ3。
Young’s modulus 杨氏模量 A term used synonymously with modulus of elasticity. The ratio of tensile or compressive stresses to the resulting strain.
与弹性模量同义的术语。拉伸或压缩应力与产生应变的比率。
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。
Torque coefficient 扭矩系数 1. (KT) For a propeller of diameter D, a non-dimensional parameter defined by KT = T/ρΩ2D5 where Ω is the rotational speed (in rad/s) and ρ is the fluid density. 2. (CT) An alternative to (1) for a wind turbine, defined by CT = 2T/ρV2AR where V is the wind speed, A is the swept area of the blades, and R is the blade radius. 3. (K) An empirical coefficient used to calculate the torque T required to achieve an axial load F in a bolt according to T = KFd where d is the nominal bolt diameter.
1.(KT)对于直径为D的螺旋桨,由KT=T/ρΩ2D5定义的无量纲参数,其中Ω是转速(单位为rad/s),ρ是流体密度。2.(CT)对于风力涡轮机(1)的替代方案,由CT=2T/ρV2AR定义,其中V是风速,a是叶片的扫掠面积,R是叶片半径。3.(K)经验系数,用于根据T=KFd计算螺栓中实现轴向载荷F所需的扭矩T,其中d是螺栓标称直径。
Finishing temperature 终轧温度 The temperature at which hot working is completed.
完成热加工的温度。
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。
Striation 条纹组织 A fatigue fracture feature, often observed in electron micrographs, that indicates the position of the crack front after each succeeding cycle of stress. The distance between striations indicates the advance of the crack front across that crystal during one stress cycle, and a line normal to the striation indicates the direction of local crack propagation.
一种疲劳断裂特征,通常在电子显微照片中观察到,表明每次应力循环后裂纹前沿的位置。条纹之间的距离表示在一个应力循环期间裂纹前沿穿过该晶体的前进,垂直于条纹的线表示局部裂纹扩展的方向。
Following flank 跟随侧翼 The flank of a thread opposite to the leading flank.
与前牙面相对的螺纹牙面。
Elbow 肘部 1. A fitting that connects the ends of two pipes at an angle, 45°, 90°, and 180° being the most common. 2. The third joint on an articulated robot corresponding to the human elbow.
1.以45°、90°和180°角连接两个管道端部的配件。2.示例关节机器人上的第三关节对应于人的肘部。
Tow 拖拉 1. To cause a vehicle to move by pulling with a rope, chain, bar, etc. 2. A bundle of  fibres employed in reinforcement.
1.用绳子、链条、钢筋等拉动车辆移动。2.用于加固的纤维束。
Displacement 移位 The distance that a chosen measurement point on a cracked specimen displaces normal to the crack plane as the crack grows.
随着裂纹扩展,裂纹试样上选定的测量点垂直于裂纹平面位移的距离。
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。
Load range, P 负载范围P In fatigue, the algebraic difference between the maximum and minimum loads in a fatigue cycle.
在疲劳中,疲劳循环中最大和最小载荷之间的代数差。
Pitch 沥青节距 The nominal distance between two adjacent thread roots or crests. In screw threads, the distance from a point on one thread to a corresponding point on the next thread measured parallel to the axis. In the case of spur gears, indicates the size of the gear teeth and is correctly called diametral pitch.
两个相邻螺纹根部或顶部之间的标称距离。在螺纹中,从一根螺纹上的一点到下一根螺纹对应点的距离,平行于轴线测量。对于正齿轮,表示齿轮齿的尺寸,正确地称为径向节距。
Fastener with waisted shank 带腰柄的紧固件 Finished fastener with a shank diameter of ds < d2.
柄径ds
Ablative materials 烧蚀材料 Materials, especially coating materials, designed to provide thermal protection to a body in a fluid stream through the loss of mass.
材料,尤其是涂层材料,旨在通过质量损失为流体流中的物体提供热保护。
Condensing boiler 冷凝锅炉 A relatively small industrial or domestic boiler that burns sulfur-free natural gas so that the products of combustion do not contain sulfuric acid and can be allowed to condense on heat-transfer surfaces without danger of corrosion.
一种相对较小的工业或家用锅炉,燃烧无硫天然气,因此燃烧产物不含硫酸,并且可以在传热表面上冷凝而没有腐蚀的危险。
Sound pressure (Unit μPa) 声压(单位:μPa) The instantaneous deviation of pressure from the ambient pressure caused by the passage of a sound wave, which can be measured by a microphone in air and a hydrophone in water.
声波传播引起的压力与环境压力的瞬时偏差,可通过空气中的麦克风和水中的水听器测量。
Elastic limit 弹性极限 The maximum stress which a material is capable of sustaining without any permanent strain (deformation) remaining on complete release of the stress.
材料在完全释放应力时能够承受的最大应力,且不会留下任何永久应变(变形)。
Valve 阀门 Any of various manual or automatic devices that are able to initiate, regulate, or stop the flow of a fluid through a conduit or from a closed container.
任何一种手动或自动装置,能够启动、调节或停止通过导管或封闭容器的流体流动。
Stress area 应力面积 The effective cross-sectional area of the threaded section of a fastener. Used to compute average stress levels in that section. Based on the mean of pitch and minor diameters.
紧固件螺纹部分的有效横截面积。用于计算该截面中的平均应力水平。基于节距和小直径的平均值。
Archimedes screw 阿基米德螺旋泵 A machine which comprises a rotating helical blade inside a closefitting tube, which may be used to pump liquids, slurries (such as sewage), granular materials, etc. If water flows into the top of an inclined or vertical Archimedes screw, the screw will rotate and can be used to drive an electrical generator.
一种机器,它在紧密的管子内包含一个旋转的螺旋叶片,可用于泵送液体、泥浆(如污水)、颗粒材料等。如果水流入倾斜或垂直的阿基米德螺杆的顶部,螺杆将旋转,可用于驱动发电机。
Burning 燃烧化 (1) Permanently damaging a metal or alloy by heating to cause either incipient melting or intergranular oxidation. See overheating, grain-boundary liquation. (2) In grinding, getting the work hot enough to cause discoloration or to change the microstructure by tempering or hardening.
(1)通过加热导致初期熔化或晶间氧化而永久损坏金属或合金。参见过热、晶界液化。(2)在磨削过程中,使工件热到足以引起变色或通过回火或硬化改变微观结构。
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。
Cotter pin 开口销 (cotter) 1. A tapered wedge or pin passing through a tapered slot or hole in one member and bearing against a second member to fix it in location. 2. A split cotter is commonly called a split pin. A pin with two legs. With legs together, the pin is placed through the hole in a clevis pin. The legs are then opened outward to prevent the cotter pin from backing out of the hole. The cotter pin, in turn, prevents the load-bearing clevis pin from backing out of its retaining hole.
(开口)1.锥形楔子或销钉穿过一个构件中的锥形槽或孔,并支撑在第二个构件上以将其固定到位。2.开口开口通常称为开口销。相当于有两条腿的别针,将支腿放在一起,销钉穿过U形夹销上的孔。然后将支腿向外打开以防止开口销从孔中退出。开口销反过来防止承重U形夹销从其固定孔中退出。
Profiling machine 仿形机 (profile milling machine) A milling machine in which the cutter is guided by the contour of a pattern having the required shape.
(仿形铣床)铣刀由具有所需形状的图案轮廓引导的铣床。
Rated load (Unit N) 额定负荷(单位:N) The maximum load that a structure or component has been designed to carry.
结构或部件设计承受的最大荷载。
Slenderness ratio 长细比 The effective unsupported length of a uniform column divided by the least radius of gyration of the cross-sectional area.
均匀柱的有效无支撑长度除以横截面积的最小回转半径。
Circlip 卡簧 (snap ring) An external or internal retaining ring that locates parts of circular cross section in an axial direction. It consists of an incomplete ring, with holes on either side of the gap, that may be expanded by a plier-like tool to pass into a groove in a shaft or contracted to pass into a groove in a bore.
(卡环)在轴向定位圆形横截面部分的外部或内部保持环。它由一个不完整的环组成,在间隙的任一侧都有孔,可以通过钳形工具将其扩展以进入轴中的凹槽或收缩以进入孔中的凹槽。
Shear stress (Unit Pa) 剪应力(单位Pa) (1) A stress that exists when parallel planes in metal crystals slide across each other. (2) The stress component tangential to the plane on which the forces act. Also known as tangential stress. (shearing stress, tangential stress, τ) 1. The stress which acts parallel to any plane within a solid material. It can arise due to a bending moment, a shear force, or torque applied to the body. 2. The stress corresponding to velocity gradients within a flowing viscous fluid.
(剪应力,切向应力,τ)(1)当金属晶体中的平行平面彼此滑动时存在的应力。(2)与力作用平面相切的应力分量。也称为切向应力。1.平行于固体材料内任何平面的应力。它可能是由于施加在身体上的弯矩、剪力或扭矩引起的。2.对应于流动粘性流体内的速度梯度的应力。
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。
Avogadro constant 阿伏伽德罗常数 (Avogadro number, NA) A fundamental physical constant with the fixed numerical value 6.022 140 76 × 1023 mol−1. The mole contains exactly this number of elementary entities. A minor adjustment to the value of the Avogadro constant was made effective on 20 May 2019.
(阿伏伽德罗数,NA)一个固定数值为6.02214076×1023mol的基本物理常数−摩尔正好包含这个数量的基本实体。对阿伏伽德罗常数值的微小调整于2019年5月20日生效。
Outside diameter (Unit m) 外径(单位:m) (external diameter, OD) The diameter of a circular cylindrical tube or a sphere measured between opposite points on the external surface.
(外径,OD)在外表面上的相对点之间测量的圆柱管或球体的直径。
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。
International Practical Temperature Scale (IPTS) 国际实用温标(IPTS) A close approximation to the thermodynamic temperature scale based upon the triple points of hydrogen (13.8 K), neon (24.6 K), oxygen (54.4 K), argon (83.8 K), mercury (234.3 K), and water (273.2 K); the melting point of gallium (302.9 K); and the freezing points of indium (429.7 K), tin (505.1 K), zinc (692.7 K), aluminium (933.5 K), silver (1 234.9 K), gold (1 337.3 K), and copper (1
基于氢(13.8K)、氖(24.6K)、氧(54.4K)、氩(83.8K),汞(234.3K)和水(273.2K)的三相点的热力学温度标度的近似值;镓的熔点(302.9K);铟(429.7K)、锡(505.1K)、锌(692.7K),铝(933.5K)、银(1234.9K)、金(1337.3K)和铜等。
Gasket stress 垫片应力 The contact stress exerted on the gasket by the joint members.
连接件施加在垫片上的接触应力。
Linear (tensile or compressive) strain 线性(拉伸或压缩)应变 The change per unit length due to force in an original linear dimension. An increase in length is considered positive.
由于原始线性尺寸中的力,每单位长度的变化。长度的增加被认为是正的。
Pressure regulator 压力调节器 (pressure-regulating valve) A device installed in a pneumatic or gas system to maintain the downstream pressure at the required level.
(压力调节阀)安装在气动或气体系统中以将下游压力保持在所需水平的装置。
Pressure-relief valve 减压阀 A valve that limits the maximum pressure in a pressure vessel or fluid-power system to a specified level.
将压力容器或流体动力系统中的最大压力限制在规定水平的阀门。
Spring temper 弹簧回火 A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about two-thirds of the way from full hard to extra spring temper.
非铁合金和一些铁合金的一种回火,其特点是抗拉强度和硬度约为全硬回火到超弹性回火的三分之二。
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。
Hardenability 淬透性 Defined as the ability of a ferrous material to acquire hardness after austenitization and quenching. The relative ability of a ferrous alloy to form martensite when quenched from a temperature above the upper critical temperature. Hardenability is commonly measured as the distance below a quenched surface where the metal exhibits a specific hardness (50 HRC, for example) or a specific percentage of martensite in the microstructure.
定义为黑色金属材料在奥氏体化和淬火后获得硬度的能力。铁合金从高于上临界温度的温度淬火时形成马氏体的相对能力。淬透性通常以淬火表面下方的距离来测量,金属在淬火表面处表现出特定硬度(例如50HRC)或微观结构中马氏体的特定百分比。
Crank pin 曲柄销 It is a short shaft parallel to the axis of the crankshaft but radially offset from it, to which is attached the big end of a connecting rod in a bearing. Sometimes the crank pin is supported at one end only (a wrist pin) but in built-up or one-piece forged crankshafts, the crank pin is supported by thick plates (crank arms, crank webs) at either end.
它是一个短轴,平行于曲轴的轴线,但径向偏移,轴承中连杆的大端连接到该短轴上。有时曲柄销仅在一端支撑(腕销),在组合式或整体锻造曲轴中,曲柄销在两端由厚板(曲柄臂、曲柄腹板)支撑。
Tensile stress (Unit Pa) 拉应力(单位Pa) A stress that causes two parts of an elastic body, on either side of a typical stress plane, to pull apart. A stress that tends to stretch a component, or local region of a component, when under load. In simple tension it results from the applied axial load, but tensile stresses occur in bending, torsion and other forms of loading.
一种应力,使弹性体的两个部分在典型应力平面的任一侧分离。在负载下,倾向于拉伸部件或部件局部区域的应力。在简单拉伸中,它由施加的轴向载荷产生,但拉伸应力发生在弯曲、扭转和其他形式的载荷中。
Closed system 封闭系统 A closed thermodynamic system consists of a fixed amount of mass. No mass can cross its boundary although energy can, in the form of work or heat, and its volume can change.
一个封闭的热力学系统由一定量的质量组成。能量可以以功或热的形式存在,其体积可以改变,但没有质量可以越过它的边界。
Impact strength 1. (Unit Pa) 冲击强度1.(单位Pa) The stress to cause failure (by yielding or fracture) under conditions of high strain rate. 2. (Unit J) A term sometimes used to describe the energy required to fracture a specimen in a Charpy or Izod impact test even though the unit is not that of strength.
在高应变率条件下导致失效(通过屈服或断裂)的应力。2.(单位J)有时用于描述在夏比或悬臂梁式冲击试验中使样品断裂所需的能量,即使单位不是强度单位。
Salt bath heat treatment 盐浴热处理 Heat treatment carried out in a bath of molten salt.
在熔融盐浴中进行的热处理。
Zirconia-toughened alumina composites 氧化锆增韧氧化铝复合材料 (ZTA composites) Ceramic composites based on aluminium oxide to which zirconium oxide is added, resulting in improved fracture toughness.
(ZTA复合材料)基于氧化铝的陶瓷复合材料,其中添加了氧化锆,从而提高了断裂韧性。
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。
Impact extrusion 冲击挤压 The extrusion of separate components of soft metals whose properties permit the action to be performed quickly.
挤压单独的软金属组件,其特性允许快速执行操作。
Torsion 扭矩 A twisting deformation of a solid body about an axis in which lines that were initially parallel to the axis become helices. The twisting of an object about an axis due to an applied couple (torque).
一种固体绕轴的扭转变形,在该变形中,最初平行于轴的线变成螺旋线。由于施加的力偶(扭矩),物体绕轴扭曲。
Dynamic coupling 动态耦合 In vibrations, the existence of inertial terms depending on mass in the governing equations, so that there is only a force if there is a corresponding acceleration.
在振动中,惯性项的存在取决于控制方程中的质量,因此只有当有相应的加速度时才有力。
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。
Atmosphere 大气 1. (atm) An obsolete (non-SI) unit of pressure equal to 101 325 Pa or 1.013 25 bar and approximately equal to the atmospheric pressure (barometric pressure) measured at mean sea level.
1.(atm)一种已被淘汰的(非SI)压力单位,等于101325Pa或1.01325bar,大约等于在平均海平面测量的大气压力(大气压)。
Compression test 压缩测试 A method for assessing the ability of a material to withstand compressive loads. The determination of the stress–strain curve of a material by axial loading of a specimen in compression. In brittle materials failure is in the elastic range; more ductile materials will yield before fracture; very ductile materials will plastically deform extensively before failure. The compression strength (compressive strength), with unit Pa, is the compressive stress that causes failure in a component or structure.
一种评估材料承受压缩载荷能力的方法。通过压缩试样的轴向载荷确定材料的应力-应变曲线。在脆性材料中,破坏在弹性范围内;韧性更强的材料在断裂前会屈服;韧性很强的材料在失效前会发生广泛的塑性变形。抗压强度(抗压强度),单位为Pa,是导致部件或结构失效的压应力。
Galilean transformation 伽利略变换 In steady fluid flow, the addition or subtraction of a constant velocity to the entire flowfield, e.g. so that flow can be considered relative to a moving object or flow feature, such as a shock wave.
在稳定的流体流动中,对整个流场增加或减少恒定速度,例如,可以考虑相对于移动物体或流动特征(例如冲击波)流动。
Infinite life diagram 无限疲劳寿命图 A simple plot experimentally derived fatigue-life data, showing the conditions required for infinite life.
一个简单的曲线图,实验得出的疲劳寿命数据,显示了无限寿命所需的条件。
Thermal compressor 热压缩机 1. (thermocompressor) A jet compressor used to boost the pressure of low-pressure waste or exhaust steam. 2. A device consisting of an absorber, a generator, a pump, and a throttling device, used instead of a mechanical vapour compressor in an absorption-cooling refrigeration system.
1.(热压缩机)用于提升低压废蒸汽或排气压力的喷射压缩机。2.一种由吸收器、发电机、泵和节流装置组成的装置,用于替代吸收冷却制冷系统中的机械蒸汽压缩机。
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。
Poisson’s ratio (ν) 泊松比(ν) The absolute value of the ratio of transverse (lateral) strain to the corresponding axial strain resulting from uniformly distributed axial stress below the proportional limit of the material.
横向(侧向)应变与相应轴向应变之比的绝对值,该比值由低于材料比例极限的均匀分布的轴向应力产生。
Plug gauge 塞规 A steel gauge used to determine the dimension or dimensions of a hole. It may be straight or tapered, and is typically circular, but in principle can have any cross section.
用于确定孔的尺寸的钢制量规。它可以是直的或锥形的,通常是圆形的,原则上可以有任何横截面。
Wrinkling 起皱 A wavy condition obtained in deep drawing of sheet metal, in the area of the metal between the edge of the flange and the draw radius. Wrinkling may also occur in other forming operations when unbalanced compressive forces are set up.
在金属板深冲过程中,在法兰边缘和拉深半径之间的金属区域内获得的波浪状状态。当设置不平衡压缩力时,在其他成形操作中也可能发生起皱。
Acid rain 酸雨 Any form of precipitation, including rain, snow, sleet, fog, dew, and particulates, which contains higher than normal levels of sulfuric and nitric acids. These acids result from natural and man-made emissions of sulfur dioxide and oxides of nitrogen, respectively. Acid soot consists of unburned carbon particles, typically larger than 10 μm, in the atmosphere contaminated with sulfuric acid. The particles result from poor combustion of fossil fuels.
任何形式的降水,包括雨、雪、雨夹雪、雾、露水和颗粒物,其中含有高于正常水平的硫酸和硝酸。这些酸分别来自二氧化硫和氮氧化物的自然排放和人为排放。酸烟灰由未燃烧的碳颗粒组成,通常大于10微米,在被硫酸污染的大气中。这些颗粒是化石燃料燃烧不良造成的。
Crack 裂缝 A thin fissure-like defect in a component or structure across which material continuity is lost and which reduces the strength of the body.
部件或结构中的细裂缝状缺陷,材料连续性丧失并降低了身体的强度。
Double tempering 双回火 A treatment in which a quench-hardened ferrous metal is subjected to two complete tempering cycles, usually at substantially the same temperature, for the purpose of ensuring completion of the tempering reaction and promoting stability of the resulting microstructure.
一种处理,其中淬火硬化的黑色金属经过两个完整的回火循环,通常在基本相同的温度下,以确保完成回火反应并提高所得微观结构的稳定性。
Scuffing 擦伤 A form of adhesive wear that produces superficial scratches or a high polish on the rubbing surfaces. It is observed most often on inadequately lubricated parts.
粘着磨损的一种形式,在摩擦表面上产生表面划痕或高度抛光。通常在润滑不足的零件上观察到。
Modulus of rupture 断裂模量 Nominal stress at fracture in a bend test or torsion test. In bending, modulus of rupture is the bending moment at fracture divided by the section modulus. In torsion, modulus of rupture is the torque at fracture divided by the polar section modulus.
弯曲试验或扭转试验中的标称断裂应力。在弯曲中,断裂模量是断裂时的弯矩除以截面模量。在扭转中,断裂模量是断裂时的扭矩除以极截面模量。
Concentration ratio 浓度比 For a concentrating solar collector, the ratio of the projected area of the concentrator facing the solar beam to the actual area of the receiver.
对于聚光太阳能集热器,集中器面向太阳光束的投影面积与接收器的实际面积之比。
Toothed gearing 齿轮传动 In principle, friction between circular discs in tangential contact could be used to transmit rotation and power between shafts, but the power level would be very limited and the velocity ratio affected by slip. To make the drive positive, gear wheels are used instead in which teeth extend above and below the diameters (the pitch-circle diameters) of discs in ideal rolling contact. The diagram shows the nomenclature for spur gears, the simplest type of gearing between parallel shafts, which are cylindrical in shape with straight teeth parallel to the axis of rotation.
原则上,切向接触的圆盘之间的摩擦可用于在轴之间传递旋转和动力,但动力水平非常有限,速比受滑动的影响。为了使驱动积极,使用齿轮代替,齿轮中的齿延伸到理想滚动接触的圆盘直径(节圆直径)的上方和下方。该图显示了直齿轮的名称,这是平行轴之间最简单的齿轮传动类型,其形状为圆柱形,直齿平行于旋转轴。
Fracture mechanisms 断裂机制 The microstructural mechanisms that cause fracture, such as void initiation, growth and coalescence, cleavage.
导致断裂的微观结构机制,如空隙的萌生、生长和聚结、解理。
constitutive equation 本构方程 (constitutive relation) 1. In solid mechanics or fluid mechanics, an algebraic or numerical relation for the dependency of stress on deformation, strain, strain rate, temperature, etc. in a material. In solid mechanics such a relation is sometimes called an equation of state. Simple linear examples include Hooke’s law and Newton’s viscosity law. 2. In heat transfer, a relation, such as Fourier’s law of heat conduction, connecting heat flux with temperature gradient.
(本构关系)1.在固体力学或流体力学中,应力与材料的变形、应变、应变率、温度等之间的代数或数值关系。在固体力学中,这种关系有时称为状态方程。简单的线性例子包括胡克定律和牛顿粘度定律。2.在传热学中,将热流与温度梯度联系起来的一种关系,如傅立叶热传导定律。
Slug wrench 缓动扳手 A box wrench with an anvil on the end of the handle. Torque is produced by striking the anvil with a sledge hammer.
柄端有铁砧的套筒扳手。扭矩是通过用大锤敲击铁砧产生的。
Shear strength 抗剪强度 The maximum shear stress that a material is capable of sustaining. Shear strength is calculated from the maximum load during a shear or torsion test and is based on the original dimensions of the cross section of the specimen.
材料能够承受的最大剪切应力。抗剪强度根据剪切或扭转试验期间的最大载荷计算,并基于试样横截面的原始尺寸。
Stability 稳定性 1. A term relating to whether a body, structure, system, or flow is in a state of stable, unstable, or neutral equilibrium. 2. In numerical analysis, whether numerical errors, such as roundoff or input-data errors, are damped, propagate, or cause divergence of the solution as the numerical method proceeds. 3. A control system is often described as stable when a step change in input results in a steady output without continuing oscillation.
1.与物体、结构、系统或流是否处于稳定、不稳定或中性平衡状态有关的术语。2.在数值分析中,随着数值方法的进行,数值误差(如舍入误差或输入数据误差)是否衰减、传播或导致解发散。3.当输入的阶跃变化导致稳定输出而无持续振荡时,控制系统通常被描述为稳定的。
Scratch hardness 划痕硬度 The resistance of a material, such as a metal, alloy, plastic, or mineral, to scratching by a much harder indenter, such as a diamond stylus, moved slowly across the surface. The scratch hardness number is computed from the loads and the dimensions of the residual scratch.
一种材料(如金属、合金、塑料或矿物)对更硬的压头(如金刚石触针)划伤的抵抗力,在表面上缓慢移动。根据载荷和残余划痕的尺寸计算划痕硬度值。
Relaxation rate 松弛率 The absolute value of the slope of a stress-relaxation curve at a given time.
给定时间应力松弛曲线斜率的绝对值。
Thermocouple 热电偶 A device for measuring temperature, consisting of lengths of two dissimilar metals or alloys that are electrically joined at one end and connected to a voltage-measuring instrument at the other end. When one junction is hotter than the other, a thermal electromotive force is produced that is roughly proportional to the difference in temperature between the hot and cold junctions.
一种测量温度的装置,由两种不同的金属或合金组成,一端电连接,另一端与电压测量仪相连。当一个结比另一个结更热时,产生的热电动势大致与热结和冷结之间的温差成比例。
Kinetic friction 动摩擦 (dynamic friction, sliding friction) (Unit N) The sliding resistance to relative motion of two surfaces in contact with each other.
(动摩擦,滑动摩擦)(单位N)两个相互接触的表面相对运动的滑动阻力。
Full hard 全硬化 A temper of nonferrous alloys and some ferrous alloys corresponding approximately to a coldworked state beyond which the material can no longer be formed by bending. In specifications, a full hard temper is commonly defined in terms of minimum hardness or minimum tensile strength (or, alternatively, a range of hardness or strength) corresponding to a specific percentage of cold reduction following a full anneal. For aluminum, a full hard temper is equivalent to a reduction of 75% from dead soft ; for austenitic stainless steels, a reduction of about 50 to 55%.
有色金属合金和一些铁合金的回火状态,大致对应于冷加工状态,超过该状态,材料就不能再通过弯曲形成。在规范中,完全硬质回火通常定义为与完全退火后的特定冷压下率百分比相对应的最小硬度或最小抗拉强度(或者,硬度或强度范围)。对于铝来说,完全硬回火相当于从极软状态减少75%;对于奥氏体不锈钢,减少约50%至55%。
Pascal (Pa) 帕斯卡(Pa) The SI unit of pressure, 1 Pa = 1 N/m².
压力的国际单位制,1Pa=1N/m²。
Valve spring 气门弹簧 The spring that restores a valve to its closed position after having been opened, and is also intended to prevent valve bounce.
在阀门打开后将其恢复到关闭位置的弹簧,也用于防止阀门反弹。
Sigma-phase embrittlement σ相脆化 Embrittlement of iron-chromium alloys (most notably austenitic stainless steels) caused by precipitation at grain boundaries of the hard, brittle intermetallic sigma phase during long periods of exposure to temperatures between approximately 565 and 980 °C (1050 and 1800 °F). Sigmaphase embrittlement results in severe loss in toughness and ductility and can make the embrittled material structure susceptible to intergranular corrosion.
铁铬合金(最显著的是奥氏体不锈钢)的脆化是由于在长时间暴露于约565至980°C(1050至1800°F)的温度下,硬脆金属间化合物σ相的晶界处沉淀造成的。σ相脆化导致韧性和延展性的严重损失,可使脆化的材料结构易于发生晶间腐蚀。
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。
Anti-freeze 防冻液 A substance such as ethylene glycol added to the cooling system of a watercooled engine to lower the freezing point of the cooling water and also inhibit the formation of rust and other deposits.
一种物质,如乙二醇,添加到水冷发动机的冷却系统中,以降低冷却水的冰点,并抑制生锈和其他沉积物的形成。
Guided-bend test 导向弯曲试验 A test in which the specimen is bent to a definite shape by means of a punch (mandrel) and a bottom block.
用冲头(心轴)和底块将试样弯曲成一定形状的试验。
Decompression chamber 减压舱 A chamber in which ambient-air pressure can be increased to levels found in deep-sea diving. It is used to gradually acclimatize divers back to normal conditions and avoid ‘the bends’.
环境气压可以提高到深海潜水水平的腔室。它用于逐渐使潜水员适应正常条件,避免“弯曲”。
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)。
Pressure snubber 压力缓冲器 (pressure-pulse snubber) A device used for filtering, dampening, and the protection of transducers, pressure gauges, and switches, from pressure surges, pressure spikes, and water hammer. A typical design uses a fixed mesh or porous metal disc installed in an inline body. In a piston-type pressure-gauge snubber, a piston is forced against an orifice leading to the gauge.
(压力脉冲缓冲器)一种用于过滤、阻尼和保护传感器、压力表和开关免受压力浪涌、压力尖峰和水锤影响的装置。典型的设计使用安装在内联阀体中的固定网格或多孔金属盘。在活塞式压力表缓冲器中,活塞被压靠在通向压力表的孔口上。
Radial load (Unit N) 径向负荷(单位:N) 1. Centrifugal loading induced in a rotating body. 2. (through-wallthickness load) The radial component of loading arising from internal or external pressurization of a closed vessel. There will also be axial and hoop loading.
1.旋转体中产生的离心载荷。2.(贯穿壁厚载荷)由封闭容器的内部或外部加压产生的载荷的径向分量。还存在轴向和环向载荷。
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。
Hot shortness 热脆性 The reduction of ductility in steels at high temperatures caused by melting of sulfides that wet grain boundaries and spread along them.
高温下钢的延展性降低,这是由于硫化物的熔化润湿晶界并沿晶界扩散而引起的。
Bolt 螺栓 (machine bolt) A fastener in the form of an externally-threaded cylinder with a head on one end that is inserted through holes in assembled parts that are then held together by a nut tightened on to the thread. A bolt has an unthreaded region below the head so that when located in a hole, transverse loads are borne by two plain cylindrical surfaces in contact. In contrast, use of a machine screw, that has threads all along its length, results in threads bearing against the plain surface of a hole. Officially, a threaded fastener designed to be used with a nut.
(机械螺栓)外螺纹圆柱状紧固件:一端有头的紧固件,通过装配零件上的孔插入,然后通过拧紧到螺纹上的螺母固定在一起。螺栓头部下方有一个无螺纹区域,因此当位于孔中时,横向载荷由两个接触的平面圆柱面承担。相反,使用沿其长度具有螺纹的机器螺钉,会导致螺纹支撑在孔的平面上。正式情况下,螺纹紧固件设计用于与螺母一起使用。
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。
Damage tolerance 损伤容限 (defect tolerance) A design philosophy that takes into account initial imperfections, crack-growth rates and conditions at final fracture, and uses fracture mechanics to demonstrate that cracks should not grow to their critical length within the design life (or at least should be capable of ready detection).
(缺陷公差)考虑初始缺陷、裂纹扩展速率和最终断裂条件的设计理念,并使用断裂力学证明裂纹不应在设计寿命内增长到其临界长度(或至少应能够随时检测)。
Oil hardening 油回火 The formation of martensite before tempering by quenching suitable steels in oil at lower cooling rates than given by water quenching, thus reducing the likelihood of component fracture or severe residual stresses. Quench-hardening treatment involving cooling in oil.
通过在油中以低于水淬的冷却速率淬火合适的钢,在回火前形成马氏体,从而降低部件断裂或严重残余应力的可能性。是一种淬火硬化处理,包括在油中冷却。
Impact test 碰撞测试 A test for determining the energy absorbed in fracturing a test piece at high velocity, as distinct from static test. The test may be carried out in tension, bending, or torsion, and the test bar may be notched or unnotched.
测定试件在高速下破裂时吸收的能量的试验,与静态试验不同。测试可以在拉伸、弯曲或扭转条件下进行,测试杆可以有缺口或无缺口。
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。
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。
Creep limit (Unit Pa) 蠕变极限(单位Pa) The maximum allowable stress under the action of which creep deformation of a material does not exceed a specified limit.
材料在其作用下的蠕变变形不超过规定限度的最大许用应力。
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。
Olsen cup test 奥尔森杯测试 A cupping test in which a piece of sheet metal, restrained except at the center, is deformed by a standard steel ball until fracture occurs. The height of the cup at time of fracture is a measure of the ductility.
一种杯突试验,其中一块金属板,除了中心以外,被一个标准钢球变形,直到发生断裂。断裂时杯的高度是延展性的量度。
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。
Residual strength (Unit N) 剩余强度(单位:N) The strength of a damaged body containing defects induced by microcracking, thermal shock, etc.
包含由微裂纹、热冲击等引起的缺陷的受损体的强度。
Fracture test 断裂试验 A test in which a specimen is broken and its fracture surface is examined with the unaided eye or with a low-power microscope to determine such factors as composition, grain size, case depth, or internal discontinuities. 1. The recording of load-deflexion (or stress–strain) in a specimen loaded monotonically until it breaks in tension, compression, shear, or torsion. 2. In fatigue, determination of the number of cycles to fracture for a specimen under different patterns of repeated loading. 3. Experiments to determine fracture toughness.
一种试验,其中试样被破坏并用肉眼或低倍显微镜检查其断裂表面,以确定成分、晶粒尺寸、表层深度或内部不连续性等因素。1.记录单调加载试样的载荷偏转(或应力-应变),直到其在拉伸、压缩、剪切或扭转中断裂。2.在疲劳技术中,确定试样在不同重复载荷模式下的断裂循环次数。3.测定断裂韧性的实验。
Alloy 合金 1. A metallic material composed of two or more elements, one of which is usually a metal to which the other elements are added, e.g. iron-carbon or aluminium-copper (binary alloy); nickel-chromium-iron (ternary alloy). 2. A plastic produced as a blend of two or more immiscible polymers. This results in material that cannot be achieved by polymerization.
1.由两种或多种元素组成的金属材料,其中一种通常是添加了其他元素的金属,例如铁碳或铝铜(二元合金);镍铬铁(三元合金)。2.由两种或多种不混溶聚合物混合而成的塑料。这导致无法通过聚合获得的材料。
Plane strain 平面应变 The stress condition in linear-elastic fracture mechanics in which there is zero strain in a direction normal to both the axis of applied tensile stress and the direction of crack growth (i.e., parallel to the crack front); most nearly achieved in loading thick plates along a direction parallel to the plate surface. Under plane-strain conditions, the plane of fracture instability is normal to the axis of the principal tensile stress.
线弹性断裂力学中的应力条件,其中在垂直于施加拉应力轴和裂纹扩展方向(即平行于裂纹前沿)的方向上存在零应变;最接近于沿平行于板表面的方向加载厚板。在平面应变条件下,断裂失稳平面垂直于主拉应力轴。
Starting taper 起始锥度 The taper on the end of a reamer or tap which aids in starting the cut.
铰刀或丝锥端部的锥度,有助于开始切割。
Spanner (wrench) 扳手 A tool for applying torque to tighten or loosen a nut, bolt, or screw. Grip is applied by a serrated ring or an open U-shape at the end of the tool. On imperial-size spanners, the BSW and BSF marking refers to the diameter of the screw thread; similarly for BA spanners. Spanners for unified and metric threads are marked with the distance across the flats (‘A/F’) of the nut or head of the bolt.
拧紧或松开螺母、螺栓或螺丝的工具。通过工具端部的锯齿环或开口U形应用夹持。在英制扳手上,BSW和BSF标记是指螺纹的直径;类似于BA扳手。用于统一螺纹和公制螺纹的扳手在螺母或螺栓头的平面('A/F')上标记距离。
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。
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-cooled engine 风冷发动机 An internal-combustion engine directly cooled by airflow, rather than by water flowing through the engine block being cooled by a radiator.
一种由气流直接冷却的内燃机,而不是通过流经发动机缸体的水被散热器冷却。
Notch ductility 缺口延展性 The percentage reduction in area after complete separation of the metal in a tensile test of a notched specimen.
在缺口试样的拉伸试验中,金属完全分离后的面积减少百分比。
Blue annealing 蓝色退火 Heating hot-rolled ferrous sheet in an open furnace to a temperature within the transformation range and then cooling in air, in order to soften the metal. The formation of a bluish oxide on the surface is incidental.
在开放式炉中将热轧铁板加热到转变范围内的温度,然后在空气中冷却,以软化金属。在表面上形成蓝色氧化物是偶然的。
Centrifuge 离心机 A machine incorporating a rapidly spinning drum in which liquids and suspended particles of different densities are separated by centrifugal action.
一种装有快速旋转滚筒的机器,在该滚筒中,不同密度的液体和悬浮颗粒通过离心作用分离。
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。
Vickers hardness test 维氏硬度测试 An indentation hardness test employing a 136° diamond pyramid indenter (Vickers) and variable loads, enabling the use of one hardness scale for all ranges of hardness—from very soft lead to tungsten carbide. Also know as diamond pyramid hardness test.
采用136°金刚石棱锥压头(维氏硬度计)和可变载荷的压痕硬度测试,能够对从极软铅到碳化钨的所有硬度范围使用一个硬度标度。也称为钻石金字塔硬度测试。
Intercritical annealing 临界退火 Any annealing treatment that involves heating to, and holding at, a temperature between the upper and lower critical temperatures to obtain partial austenitization, followed by either slow cooling or holding at a temperature below the lower critical temperature.
任何退火处理,包括加热至并保持在上临界温度和下临界温度之间的温度,以获得部分奥氏体化,然后缓慢冷却或保持在低于下临界温度的温度。
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。
Hydrogen embrittlement 氢脆 A condition of low toughness, low ductility or cracking in metals resulting from the absorption of hydrogen. A common and troublesome form of Stress cracking. Several theories have been proposed to explain hydrogen embrittlement, but, at present, the exact mechanism is still unknown. What is known, however, is the fact that if hydrogen is trapped in a bolt by poor electroplating practices, it can encourage stress cracking. Bolts can fail, suddenly and unexpectedly, under normal loads. Premature crack growth over time under tensile stress leading to unexpected failure in certain metals, caused by small amounts of hydrogen in the microstructure. Hydrogen may enter steels during melting or heat treating, or during processes such as electroplating.
因吸收氢而导致金属韧性低、延展性低或开裂的情况,是一种常见且麻烦的应力开裂形式。在拉伸应力下,裂纹随时间过早扩展,导致某些金属发生意外失效,这是由微观结构中的少量氢引起的。在熔化或热处理过程中,或在电镀等过程中,氢可能进入钢中。已经提出了几种理论来解释氢脆,但目前,确切的机理仍然未知。已知的事实是,如果氢因电镀不当而被困在螺栓中,则会导致应力开裂。在正常载荷下,螺栓可能突然意外失效。
Screw jack 螺旋千斤顶 A lifting device (jack) consisting of a nut and square-threaded shaft at the top of which is a load-bearing pad. Rotation of the nut raises or lowers the pad.
一种起重装置(千斤顶),由螺母和方形螺纹轴组成,其顶部为承重垫。螺母的旋转可升高或降低衬垫。
Taper 变尖 A gradual, often linear, reduction in cross section or shape. A shaft or hole that gets gradually smaller toward one end.
横截面或形状的逐渐减小,通常是线性的。一端逐渐变小的轴或孔。
Clutch 离合器 A device for connecting and disconnecting rotating shafts, for example between an engine and a gearbox.
一种用于连接和断开旋转轴的装置,例如在发动机和变速箱之间。
Offset yield strength 条件屈服强度 The stress at which the strain exceeds by a specified amount (the offset) an extension of the initial proportional portion of the stress-strain curve. Expressed in force per unit area.
应变超过应力-应变曲线初始比例部分延伸规定量(偏移)的应力。以每单位面积的力表示。
Crystalline defects 结晶缺陷 The deviations from a perfect three-dimensional atomic packing that are responsible for much of the structure-sensitive properties of the materials. Crystal defects can be point defects (dislocations) or surface defects (vacancies), line defects (dislocations), or surface defects (grain boundaries).
与完美的三维原子堆积的偏差是造成材料的大部分结构敏感特性的原因。晶体缺陷可以是点缺陷(位错)或表面缺陷(空位)、线缺陷(位错)或表面缺陷(晶界)。
Forced-air quench 强制空气淬火 A quench utilizing blasts of compressed air against relatively small parts such as a gear.
利用压缩空气冲击相对较小的零件(例如齿轮)进行的淬火。
Conditioning heat treatment 调质热处理 A preliminary heat treatment used to prepare a material for desired reaction to a subsequent heat treatment. For the term to be meaningful, the exact heat treatment must be specified.
用于制备材料的初步热处理,以便对随后的热处理进行所需的反应。为了使该术语有意义,必须指定确切的热处理。
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。
Stiffness 刚度 (1) The ability of a metal or shape to resist elastic deflection.(2) The rate of stress increase with respect to the rate of increase in strain induced in the metal or shape; the greater the stress required to produce a given strain, the stiffer the material is said to be.
(1)金属或形状抵抗弹性变形的能力。(2)所述应力增加速率相对于在所述金属或形状中诱导的应变增加速率;产生给定应变所需的应力越大,材料就越硬。
Combined heat and power plant 热电联产电厂 (CHP plant, COGEN, cogeneration plant, total-energy plant) A plant for the simultaneous production of more than one useful form of energy from the same energy source, such as process heat and electric power. In the arrangement shown, partially expanded steam is extracted from the steam turbine and used to produce process heat.
(CHP工厂、COGEN、热电联产工厂、总能源工厂)从同一能源(如过程热能和电力)同时生产一种以上有用能源的工厂。在所示的布置中,部分膨胀的蒸汽从蒸汽轮机中提取并用于产生过程热量。
Thread grinding 螺纹磨削 A method for producing or finishing very precise screw threads using a profiled grinding wheel.
一种使用异形砂轮生产或精加工非常精密螺纹的方法。
Threaded fastener 螺纹紧固件 Studs, bolts, and screws of all sorts, with associated nuts. One of the most interesting, complex, useful—and frustrating—components yet devised.
各种螺柱、螺栓和螺钉,以及相关的螺母。
Brittle fracture 脆性断裂 The fracture of a component or structure in the globally-elastic range of loading, so that the broken pieces may be refitted to regain the original article. Separation of a solid accompanied by little or no macroscopic plastic deformation. Typically, brittle fracture occurs by rapid crack propagation with less expenditure of energy than for ductile fracture.
部件或结构在全局弹性载荷范围内的断裂,以便可以将破碎的碎片重新装配以恢复原始物品。固体的分离伴随着很少或没有宏观塑性变形。通常,脆性断裂通过快速裂纹扩展发生,能量消耗比韧性断裂少。
Crack length (depth) (a) 裂纹长度(深度)(a) In fatigue and stress corrosion cracking, the physical crack size used to determine the crack growth rate and the stress-intensity factor. For the compact-type specimen, crack length is measured from the line connecting the bearing points of load application. For the center-cracked-tension specimen, crack length is measured from the perpendicular bisector of the central crack.
在疲劳和应力腐蚀裂纹中,用于确定裂纹扩展速率和应力强度因子的物理裂纹尺寸。对于紧凑型试样,裂纹长度从连接载荷施加点的线开始测量。对于中心裂纹拉伸试样,从中心裂纹的垂直平分线测量裂纹长度。
Zone melting (zone refining) 区域熔炼(区域精炼) A process of purification of materials in which a narrow molten zone is moved along the length of the material, resulting in impurities being segregated at one end.
一种净化材料的过程,其中一个狭窄的熔融区沿材料长度移动,导致杂质在一端分离。
Stove bolt 炉用螺栓 This bolt has been so named because of its use in stove building. It is made in a number of different forms, either with a round button, or flat countersunk head, the head having a slot for a screwdriver and the threaded end being provided with a square or hexagon nut.
这种螺栓因其在炉灶建筑中的用途而得名。它有多种不同的形式,有圆形按钮或平沉头,头部有螺丝刀槽,螺纹端有方形或六角螺母。
Fin A thin projecting rib.
一根细长的凸肋。
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。
Adhesive strength 粘合强度 The strength of an adhesively bonded joint, usually measured in tension (perpendicular to the plane of the bonded joint) or in shear
粘合接头的强度,通常以拉伸(垂直于粘合接头的平面)或剪切测量
Plane-stress fracture toughness (Kc) 平面应力断裂韧性(Kc) In linear-elastic fracture mechanics, the value of the crack-extension resistance at the instability condition determined from the tangency between the R-curve and the critical crack-extension force curve of the specimen.
在线弹性断裂力学中,由试样的R曲线和临界裂纹扩展力曲线之间的切线确定的不稳定条件下裂纹扩展阻力的值。
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。
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。
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。
Joint space 关节空间 The description of the position and orientation of a robot in terms of the rotational angles and translational positions of the joints. Kinematic analysis, normally using homogeneous transforms, allows conversion between this description and the end‐effector position and orientation in x,y,z space.
根据关节的旋转角度和平移位置描述机器人的位置和方向。通常使用齐次变换的运动学分析允许在该描述与x、y、z空间中的末端执行器位置和方向之间进行转换。
Piston pump 活塞泵 A positive-displacement pump in the basic configuration of which a piston reciprocates in a cylinder. On the suction stroke, fluid is drawn into a chamber through the inlet valve, which is then open while the outlet valve is closed. On the delivery stroke the fluid is forced out of the chamber through the outlet valve, which then opens while the inlet valve is closed. Both axial and radial configurations are common.
活塞在气缸中往复运动的一种容积泵。在吸入冲程,流体通过入口阀吸入腔室,然后在出口阀关闭时打开。在输送冲程中,流体通过出口阀被迫流出腔室,然后出口阀打开,同时入口阀关闭。轴向和径向配置都很常见。
Hard temper 硬化回火 Same as full hard temper.
和全硬化回火一样。
Cold die quenching 冷模淬火 A quench utilizing cold, flat, or shaped dies to extract heat from a part. Cold die quenching is slow, expensive, and is limited to smaller parts with large surface areas.
利用冷、平或成型模具从零件中提取热量的淬火。冷模淬火速度慢、成本高,并且仅限于表面积较大的较小零件。
Torque pack 扭矩包 A geared wrench which multiplies input torque and provides a read-out of output torque. In effect, a combination of a Torque wrench and a Torque multiplier.
一种齿轮扳手,可增加输入扭矩并提供输出扭矩读数。实际上,它是扭矩扳手和扭矩倍增器的组合。
Inclusions 夹杂物 Small pieces of nonmetallic impurities trapped within the base metal of.
存在于金属基体中的小块非金属杂质。
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。
Q-factor 品质因素 (quality factor, sharpness of resonance) A non-dimensional parameter that describes, for a given resonant mode, the sharpness of the peak in the frequency response of a lightly-damped linear oscillator: Q = ωRES/Δω where ωRES is the resonance frequency and Δω is the half-power bandwidth of the resonance. It is inversely related to the damping such that a broad peak corresponds to high damping and a narrow peak to low damping.
(品质因数,共振尖锐度)一个无量纲参数,用于描述给定共振模式下,轻阻尼线性振荡器频率响应峰值的尖锐度:Q=ωRES/Δω,其中ωRES是共振频率,Δω是共振的半功率带宽。它与阻尼成反比,因此宽峰值对应于高阻尼,窄峰值对应于低阻尼。
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。
Pin expansion test 插头膨胀试验 A test for determining the ability of a tube to be expanded or for revealing the presence of cracks or other longitudinal weaknesses in it, made by forcing a tapered pin into the open end of the tube, similar to flare test.
通过将锥形销压入管道开口端来确定管道膨胀能力或揭示其存在裂纹或其他纵向缺陷的试验,类似于扩口试验。
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。
Spring materials 弹簧材料 Mainly metals including plain-carbon and corrosion-resisting steels, phosphor bronze, spring brass, beryllium copper and nickel alloys, all of which in their workhardened states permit large reversible elastic strains without permanent deformation.
主要是金属,包括普通碳钢和耐腐蚀钢、磷青铜、弹簧黄铜、铍铜和镍合金,所有这些金属在其加工硬化状态下都允许大的可逆弹性应变而不会产生永久变形。
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。
Maximum material condition 最大材料条件 (maximum metal condition) The situation where the volume of a manufactured component corresponds to the upper limit for all toleranced external dimensions, and to the lower limit for all internal dimensions.
(最大金属条件)制造部件的体积对应于所有公差外部尺寸的上限和所有内部尺寸的下限的情况。
Residual stress (Unit Pa) 残余应力(单位Pa) Stresses that remain within a body as the result of thermal or mechanical treatment or both. (internal stress) An internal-stress system found in components that have experienced elastic unloading from non-uniform plastic-strain fields during manufacture.
由于热处理或机械处理或两者兼而有之而留在物体内的应力。(内应力)在制造期间从非均匀塑性应变场经历弹性卸载的部件中发现的内应力系统。
High-tensile bolt 高强度螺栓 (high-tension bolt) A bolt manufactured from an alloy steel that has a high tensile strength of about 1 GPa.
(高压螺栓)由合金钢制成的螺栓,具有约1GPa的高抗拉强度。
Gamma iron 加马铁 The face-centered cubic form of pure iron, stable from 910 to 1400 °C (1670 to 2550 °F).
纯铁的面心立方形式,在910至1400°C(1670 2550°F)温度范围内稳定。
Embedment 嵌入 Localized plastic deformation in heavily loaded fasteners allows one part to sink into, or smooth the surface of, a softer or more heavily loaded second part. Nuts embed themselves in joint surfaces. Bolt threads embed themselves in nut threads, etc.
重载紧固件中的局部塑性变形允许一个零件陷入较软或更重载的第二零件中,或使其表面光滑。螺母嵌入接合面中。例如螺栓螺纹嵌入螺母螺纹等。
Residual preload 残余预载荷 The tension which remains in an unloaded bolted joint after Relaxation.
松弛后未加载螺栓连接中保持的张力。
Three-quarters hard 四分之三硬度 A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about midway between those of half hard and full hard tempers.
一种非铁合金和一些铁合金的回火,其特征是抗拉强度和硬度介于半硬回火和全硬回火之间。
Extensometer 引伸计 An instrument for measuring changes in length over a given gage length caused by application or removal of a force. Commonly used in tension testing of metal specimens. Any instrument which measures the change in length of a part as the part is loaded.
一种用于测量在给定标距上由施加或移除力引起的长度变化,在零件加载时测量零件长度变化的仪器。常用于金属试样的拉力试验。
Combustion chamber 炉膛 1. In a piston engine, the volume between the head of an individual cylinder and the crown of the piston in which the fuel–air mixture burns during each power stroke of the engine. 2. (combustor) In a gas-turbine engine, a ramjet, an afterburner, or a rocket motor, the component, often cylindrical or annular in shape, in which the fuel–air mixture burns in a continuous-flow process.
1.在活塞式发动机中,在发动机的每个动力冲程中,燃料-空气混合物燃烧的单个气缸盖和活塞顶之间的体积。2.(燃烧室)在燃气涡轮发动机、冲压发动机、加力燃烧室或火箭发动机中,燃料-空气混合物在连续流动过程中燃烧的部件,通常为圆柱形或环形。
显示更多数据,请使用查询功能!