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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。
Structural-integrity analysis 结构完整性分析 Assessment of components and structures for likelihood of failure by buckling, fracture, yielding, etc. under conditions of normal and accident loading.
在正常和事故荷载条件下,评估部件和结构因屈曲、断裂、屈服等而失效的可能性。
Horsepower 马力 Unit indicating the rate at which work is done. The electrical equivalent of one horsepower is 746 watts.
单位表示完成工作的速率。一马力的电当量为746瓦。
Barrier protection 屏障保护 The coating on a fastener is said to provide barrier protection if it merely isolates the fastener from the environment. Paint, for example, provides barrier protection.
如果仅将紧固件与环境隔离,则据说紧固件上的涂层可提供屏障保护。例如,油漆提供屏障保护。
Damage 损伤 1. The deterioration of a component or structure in fault or accident conditions, reducing or preventing its ability to perform its intended function. 2. The accumulation of defects or microcracks in the microstructure of a body loaded monotonically or in fatigue, which weakens the body and can lead to crack propagation and failure.
1.部件或结构在故障或事故条件下的劣化,降低或阻止其执行预期功能的能力。2.在承受单调载荷或疲劳载荷的物体的微观结构中累积的缺陷或微裂纹,这会削弱物体,并可能导致裂纹扩展和失效。
Bánki turbine 班基涡轮机 A cross-flow, impulse-type water turbine for very low heads in which a jet of water in the form of a flat sheet passes transversely through the turbine, so going through the runner twice. The thin runner blades which run horizontally across the turbine parallel to the axis of rotation are profiled in cross section.
一种用于非常低水头的横流脉冲式水轮机,其中平板形式的水射流横向穿过涡轮机,因此穿过转轮两次。平行于旋转轴水平穿过涡轮机的薄转轮叶片在横截面上具有轮廓。
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。
Hydrodynamics 流体力学 A term sometimes used to mean fluid dynamics, even when the fluid is a gas or a liquid other than water.
有时用于表示流体动力学的术语,即使流体是气体或水以外的液体。
Rupture stress 断裂应力 The stress at failure. Also known as breaking stress.
失效时的应力。也称为破裂应力。
Square thread 方螺纹 A form of screw thread in which the cross–section of the thread forms a square, making the width of the thread equal to the space between the threads.
螺纹的一种形式,螺纹的横截面形成正方形,使螺纹的宽度等于螺纹之间的间距。
Thermoelectric converter 热电转换器 (thermoelectric generator) A device consisting of series-connected alternate n- and p-type semiconductor elements sandwiched between two ceramic plates. Due to the Seebeck effect, electrical power is generated when a temperature difference is maintained across the plates. Due to the Peltier effect, a thermoelectric converter can act as either a thermoelectric heater or a thermoelectric cooler (thermoelectric refrigerator) by passing an electrical current through it. The thermoelectric figure of merit (Z), with unit 1/K, is a dimensional parameter on which the efficiency of a thermoelectric device is primarily dependent, defined by Z = σα2/k where α is the Seebeck coefficient, σ is the electrical conductivity, and k is the thermal conductivity. The product of Z and a temperature is non-dimensional.
(热电发生器)由串联连接的交替的n型和p型半导体元件夹在两块陶瓷板之间组成的装置。由于塞贝克效应,当板之间保持温差时,就会产生电能。由于珀尔帖效应,热电转换器可以通过使电流通过而充当热电加热器或热电冷却器(热电制冷机)。热电优值(Z)和第一单元/K是一个尺寸参数,热电装置的效率主要取决于此,由Z=σα2/K定义,其中α是塞贝克系数,σ是电导率,K是热导率。Z和温度的乘积是无量纲的。
Absolute value error 绝对值误差 The magnitude of the error dlsregarding the algebraic sign, or, for a vectorial error, disregarding its function.
关于代数符号的误差幅度,或者,对于矢量误差,不考虑其函数。
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。
Natural unit system (n.u. system) 自然单位制(n.u.制) A non-SI system of units, based on fundamental constants, used in high-energy and particle physics. The n.u. of speed is the speed of light in a vacuum, c0 = 299 792 458 m/s.
基于基本常数的非国际单位制,用于高能和粒子物理n.u.速度是真空中的光速,c0=299792458m/s。
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。
Blind rivet 盲孔铆钉 A rivet that enables a connexion to be made from one side only of an assembly.
一种铆钉,可以仅从组件的一侧进行连接。
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。
Wing nut 蝶形螺母 A nut having two opposite protruding wings to permit hand tightening.
一种螺母,有两个相对突出的翼片,可以用手拧紧。
Fracture surface 断裂面 The irregular surface produced when a piece of metal is broken.
一块金属破碎时产生的不规则表面。
Turning angle (θ) 转向角(θ) The change in direction experienced by a gas flow passing through an oblique shock wave or Prandtl–Meyer expansion fan.
气流通过斜激波或Prandtl–Meyer膨胀风机时所经历的方向变化。
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。
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。
Bar 巴(气压单位) A widely used (non-SI) unit of pressure approximately equal to normal atmospheric pressure at sea level. The conversion to SI is 1 bar = 105 Pa. Unit of pressure – the pressure created by a column of€mercury 75.006 cm high at 0ºC, or about 33.45 feet of water at 4ºC. It is equal to 105 pascal. Standard atmospheric pressure (at sea level) is 1.01325 bar, or 1013.25 mb.
一种广泛使用的(非SI)压力单位,大约等于海平面上的正常大气压。转换为SI为1bar=105Pa。压力单位——0ºC时75.006厘米高的水银柱或4ºC时约33.45英尺水柱产生的压力。它等于105帕斯卡。标准大气压(海平面)为1.01325bar或1013.25mb。
Isothermal annealing 等温退火 Austenitizing a ferrous alloy and then cooling to and holding at a temperature at which austenite transforms to a relatively soft ferrite carbide aggregate.
将铁合金奥氏体化,然后冷却至奥氏体转变为相对软的铁素体碳化物集合体的温度并保持该温度。
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。
Quick coupling 快速接头 (quick disconnect, fast coupling) A hose connection allowing rapid assembly or disassembly and comprising a socket and a plug incorporating a springloaded locking mechanism.
(快速断开、快速连接)一种软管连接,允许快速组装或拆卸,包括插座和带有弹簧加载锁定机构的插头。
Finishing washer 光制垫圈 A washer designed for use with countersunk screws. Used to enhance appearance in some applications.
设计用于沉头螺钉的垫圈。在某些应用中用于增强外观。
Abradant 研磨剂 The differently sized grits of hard materials such as emery employed for grinding, polishing, etc. The abrasive grade is determined by the grit size (grit number) originally related to the hole sizes in wire sieves.
用于研磨、抛光等的硬质材料(例如金刚砂)的不同尺寸粒度。磨料等级由最初与金属丝筛孔尺寸相关的粒度(粒度数)决定。
Grain coarsening 晶粒粗化 A heat treatment that produces excessively large austenitic grains.
产生过大奥氏体晶粒的热处理。
Forging 锻造处理 The process of forming raw steel into specified shapes. Some examples of forged products would be hex bolts, clevises, and barrier pins. 1. A method of component manufacture by hammering metal by hand or by machine (drop forge, press). 2. A part made by the process of forging.
将生钢制成特定形状的过程。锻造产品的一些例子是六角螺栓、U形夹和障碍销。 1. 一种通过手工或机器锤击金属(落锻、压力机)制造部件的方法。2.通过锻造工艺制成的零件。
Critical temperature 临界温度 (1) Synonymous with critical point if the pressure is constant. (2) The temperature above which the vapor phase cannot be condensed to liquid by an increase in pressure.
(1) 如果压力恒定,则与临界点同义。(2) 高于该温度时,气相不能通过压力升高而冷凝为液体。
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。
Manometer 压力计 An instrument used in the measurement of a pressure difference in a fluid (manometry).
用于测量流体压力差(测压)的仪器。
Maximum load (Pmax) 最大负载(Pmax) (1) The load having the highest algebraic value in the load cycle. Tensile loads are considered positive and compressive loads negative. (2)Used to determine the strength of a structural member; the load that can be borne before failure is apparent.
(1)负载循环中具有最高代数值的负载。拉伸荷载视为正荷载,压缩荷载视为负荷载。(2)用于确定结构构件的强度;失效前可承受的载荷是明显的。
O-ring (O-ring seal) O形圈(O形密封圈) A toroidal ring of synthetic rubber seated in a groove machined into a flat or cylindrical surface to act as a seal.
一种环形合成橡胶环,位于加工成平面或圆柱表面的凹槽中,起密封作用。
Mechanical metallurgy 机械冶金 The science and technology dealing with the behavior of metals when subjected to applied forces.
处理金属在外力作用下的行为的科学技术。
Set screw 紧定螺钉(平头螺钉、紧定螺栓) Usually a hardened steel screw having either no head or a square head and with various degrees of points or ends to lock or tighten adjustable machine parts in position on a shaft. A short, headless screw with a recess at one end to receive a screwdriver or key, the other end being pointed, square, or otherwise shaped. Typically used to secure a pulley, gear, or other component on a shaft.
通常是一种硬化钢螺钉,无头或方头,具有不同程度的点或端部,用于将可调机械部件锁定或拧紧在轴上的适当位置。一端有凹槽,用来装螺丝刀或钥匙,另一端是尖的、方形的或其他形状的。通常用于将皮带轮、齿轮或其他部件固定在轴上。
ANSI ANSI The acronym for American National Standards Institute.
美国国家标准协会的缩写。
Lobe 凸轮 The projecting part such as rotor lobe or the cam lobe.
转子凸角或凸轮凸角等突出部分。
Transmission dynamometer 传动测功机 A dynamometer in which the power transmitted by a shaft is obtained from the product of its rotation speed and the torque determined from measured shear strains along the shaft.
一种测功机,其中轴传递的功率由其转速和扭矩的乘积获得,扭矩由沿轴测得的剪切应变确定。
Structural engineering 结构工程 A branch of civil engineering concerned with the design of buildings, dams, bridges, and other large structures.
土木工程的一个分支,涉及建筑物、水坝、桥梁和其他大型结构的设计。
Screw pair 螺旋副 Two links connected together to form a kinematic pair, in which the contacting surfaces are screw threads, so that their relative motion consists of rotation and sliding.
两个连杆连接在一起形成运动副,其中接触面为螺纹,因此它们的相对运动包括旋转和滑动。
Shoulder screw 轴肩螺钉 A screw having two or more diameters or shoulders and commonly used for supporting levers and other machine parts that have to operate freely.
一种具有两个或两个以上直径或轴肩的螺钉,通常用于支撑杠杆和其他必须自由操作的机器部件。
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。
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。
Brine quenching 盐水淬火 A quench in which brine (salt water-chlorides, carbonates, and cyanides) is the quenching medium. The salt addition improves the efficiency of water at the vapor phase or hot stage of the quenching process.
一种淬火,其中盐水(盐水-氯化物、碳酸盐和氰化物)是淬火介质。添加盐提高了水在淬火过程的气相或热阶段的效率。
Fracture strength 断裂强度 (fracture stress) (Unit Pa) The stress at which a material breaks. It is not absolute for a given material, as it depends on the laws of fracture mechanics and is size-dependent.
(断裂应力)(单位Pa)材料断裂时的应力。对于给定的材料,它不是绝对的,因为它取决于断裂力学定律,并且取决于尺寸。
Maraging steels 马氏体时效钢 Very high-strength iron alloys named after ‘martensitic’ and ‘aging’. They contain nickel, chromium, cobalt, and molybdenum, and form martensite on air cooling with a strength of about 1 GPa. When reheated to about 500°C and aged for some hours, a room-temperature strength of some 2.4 GPa is reached.
以“马氏体”和“时效”命名的超高强度铁合金。它们含有镍、铬、钴和钼,在空气冷却下形成强度约为1GPa的马氏体。当再加热至约500°C并老化数小时时,室温强度达到约2.4GPa。
Tera (T) 特拉(T) An SI unit prefix indicating a multiplier of 1012; thus terawatt (TW) is a unit of power equal to one trillion watts.
指示乘数1012的SI单位前缀;因此,太瓦(TW)是等于1万亿瓦的功率单位。
Rotary blower 旋转鼓风机 (rotary compressor) A positive-displacement gas compressor which may be of the blade type, helical-screw type, meshing-lobe type (the Roots blower), or sliding-vane type.
(旋转式压缩机)一种容积式气体压缩机,可以是叶片式、螺旋式、啮合凸角式(罗茨鼓风机)或滑动叶片式。
Thermoelastic effect 热弹性效应 The change in temperature of material under adiabatic elastic deformation, e.g. when loading is so rapid that the material is not in thermal equilibrium with its surroundings. For most materials, elastic tension lowers the temperature and compression raises it. The reverse occurs in elastomers such as rubber that exhibit entropic elasticity because stretching reduces the number of possible molecular configurations and so reduces the entropy. The thermoelastic effect gives rise to a stress–strain hysteresis loop in cyclic elastic loading and is one mechanism by which vibrational energy is dissipated internally in materials.
材料在绝热弹性变形下的温度变化,例如当加载速度如此之快,以至于材料与其周围环境不处于热平衡时。对于大多数材料,弹性张力降低温度,压缩提高温度。相反的情况发生在弹性体中,如橡胶,其表现出熵弹性,因为拉伸减少了可能的分子构型的数量,从而降低了熵。热弹性效应在循环弹性载荷中产生应力-应变迟滞回线,是振动能量在材料内部耗散的一种机制。
Grip length 夹紧长度 Combined thickness of all the things clamped together by the bolt and nut, including washers, gaskets, and joint members.
由螺栓和螺母夹紧在一起的所有部件的总厚度,包括垫圈、垫圈和接头构件。
Fog quenching 雾淬 Quenching in a fine vapor or mist.
在细蒸汽或薄雾中淬火。
Coil spring 螺旋弹簧 A spiral (‘clockwork’) or helical (cylindrical) spring. A spring steel wire wound in a spiral pattern.
螺旋(“发条”)或螺旋(圆柱形)弹簧。以螺旋状缠绕的弹簧钢丝。
Vibration-testing machine (vibrator) 振动试验机(振动器) Any machine that subjects components or systems to vibration at known amplitudes and frequencies in order to determine the response. vibratory equipment Vibrating process equipment, such as shakers, used to separate small and large particles, or feeders to supply particulate or granular material that may otherwise clog.
使部件或系统以已知振幅和频率振动以确定响应的任何机器。振动设备振动工艺设备,如用于分离小颗粒和大颗粒的振动筛,或用于供应可能堵塞的颗粒或粒状材料的给料机。
Angle of thread 螺纹角度 The included angle between the sides forming the groove of the screw thread.
形成螺纹凹槽的边之间的夹角。
Variance 方差 A measure of the squared dispersion of observed values or measurements expressed as a function of the sum of the squared deviations from the population mean or sample average.
观测值或测量值的平方离散度的度量,表示为总体平均值或样本平均值的平方偏差之和的函数。
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。
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。
Grain size 晶粒大小 A measure of the areas or volumes of grains in a polycrystalline metal, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. For metals, a measure of the areas or volumes of grains in a polycrystalline material, usually expressed as an average when the individual sizes are fairly uniform. In metals containing two or more phases, the grain size refers to that of the matrix unless otherwise specified. Grain sizes are reported in terms of number of grains per unit area or volume, average diameter, or as a grainsize number derived from area measurements.
多晶金属中晶粒的面积或体积的量度,通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中,除非另有说明,晶粒尺寸是指基体的晶粒尺寸。多晶材料中晶粒的面积或体积的量度,通常表示为单个尺寸相当均匀时的平均值。在含有两相或多相的金属中,除非另有说明,晶粒尺寸是指基体的晶粒尺寸。晶粒尺寸以每单位面积或体积的晶粒数、平均直径或从面积测量得出的晶粒尺寸数来报告。
Shoulder joint 轴肩关节 The second joint on an articulated robot, which has a horizontal axis and is analogous to the human shoulder.
关节机器人上的第二个关节,具有水平轴,类似于人的肩膀。
Linear-elastic fracture mechanics 线弹性断裂力学 A method of fracture analysis that can determine the stress (or load) required to induce fracture instability in a structure containing a cracklike flaw of known size and shape.
一种断裂分析方法,可确定在含有已知尺寸和形状裂纹状缺陷的结构中引起断裂不稳定性所需的应力(或载荷)。
Strain energy 应变能 A measure of the energy absorption characteristics of a material determined by measuring the area under the stress-strain diagram.
通过测量应力-应变图下的面积确定的材料能量吸收特性的度量。
Preload relaxation 预载松弛 Local yielding, due to excess bearing stress under nuts and bolt heads (caused by high local spots, rough surface finish, and lack of perfect squareness of bolt and nut bearing surfaces), may result in preload relaxation after preloads are first applied to a bolt.
由于螺母和螺栓头下的轴承应力过大(由局部斑点高、表面粗糙以及螺栓和螺母轴承表面缺乏完美的方正度造成),局部屈服可能会在首次向螺栓施加预载荷后导致预载荷松弛。
Liquid nitriding 液体氮化 A method of surface hardening in which molten nitrogen-bearing, fused-salt baths containing both cyanides and cyanates are exposed to parts at subcritical temperatures.
一种表面硬化方法,其中含有氰化物和氰酸盐的熔融含氮熔盐浴在亚临界温度下暴露于零件。
Crest of screw thread 螺纹牙顶 The top surface joining the two sides of flanks of a thread.
连接螺纹牙侧两侧的顶面。
Recrystallization temperature 再结晶温度 The approximate minimum temperature at which complete recrystallization of a cold-worked metal occurs within a specified time.
冷加工金属在规定时间内发生完全再结晶的近似最低温度。
Concentrated solar power plant (CSP plant) 聚光太阳能发电厂(CSP发电厂) A power plant in which solar radiation is concentrated using mirrors or lenses, typically using parabolic trough mirrors which focus solar radiation on to receiver tubes along the trough’s focal line. In an alternative arrangement molten salt, heated by solar receivers mounted on a tower, is circulated through a steam generator.
使用镜子或透镜集中太阳辐射的发电厂,通常使用抛物面槽镜,将太阳辐射沿着槽的焦线聚焦到接收管上。在另一种布置中,由安装在塔上的太阳能接收器加热的熔盐通过蒸汽发生器循环。
Ferritic stainless steels 铁素体不锈钢 Ferritic stainless steels have the ferrite (BCC) crystal structure and contain 10–28% chromium and typically 0.1–0.35% carbon (all in wt%). They are magnetic and can be hardened by cold working. They have good to moderate mechanical properties, good oxidation and corrosion resistance at elevated temperatures, and susceptibility to embrittlement at temperatures between 400 and 540°C. Used for turbine parts, hightemperature valves, automotive exhaust components, and nuclear reactor core components.
铁素体不锈钢具有铁素体(BCC)晶体结构,含有10-28%的铬,通常含有0.1-0.35%的碳(均为重量%)。它们具有磁性,可通过冷加工硬化。它们具有良好至中等的机械性能,在高温下具有良好的抗氧化性和耐腐蚀性,在400至540°C的温度下易脆化。用于涡轮零件、高温阀、汽车排气部件和核反应堆堆芯部件。
Testing machine (load-measuring type) 试验机(负载测量型) A mechanical device for applying a load (force) to a specimen.
向试样施加载荷(力)的机械装置。
Socket wrench 套筒扳手 A form of spanner with an internally ridged steel socket to fit a nut or the head of a bolt or screw.
扳手的一种形式,带有内脊钢套筒,用于安装螺母或螺栓或螺钉的头部。
Diaphragm meter 隔膜计 A dry flow meter in which there are two or more interconnected chambers, each having a diaphragm in the wall. The chambers empty and fill alternately and the flow rate of gas is determined from the movement of diaphragms. Diaphragm meters are commonly used to monitor domestic and commercial gas supply.
一种干式流量计,其中有两个或多个相互连接的腔室,每个腔室的壁上都有一个隔膜。腔室交替排空和填充,气体流速由隔膜的移动确定。隔膜流量计通常用于监测家用和商用燃气供应。
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。
Mechanical units 机械单位 The units of physical quantities, the dimensions of which includemass, length, and time.
物理量的单位,其量纲包括质量、长度和时间。
Stress corrosion cracking (SCC) 应力腐蚀开裂(SCC) A common form of Stress cracking in which an Electrolyte encourages the growth of a crack in a highly stressed bolt. Only a tiny quantity of electrolyte need be present, at the tip or face of the crack. A time-dependent process in which a metallurgically susceptible material fractures prematurely under conditions of simultaneous corrosion and sustained loading at lower stress levels than would be required in the absence of a corrosive environment. Tensile stress is required at the metal surface and may be a residual stress resulting from heat treatment or fabrication of the metal or the result of external loading. Cracking may be intergranular or transgranular, depending on the combination of alloy and environment.
一种常见的应力开裂形式,其中电解液促使高应力螺栓中的裂纹扩展。在裂纹尖端或表面,只需存在少量电解质。一种随时间变化的过程,其中冶金敏感材料在同时腐蚀和持续加载的条件下过早断裂,其应力水平低于无腐蚀环境时的要求。在金属表面需要拉应力,拉应力可以是金属的热处理或制造或外部负载产生的残余应力。裂纹可能是沿晶开裂或穿晶开裂,这取决于合金和环境的组合。
Vacuum pump 真空泵 A pump for exhausting air and non-condensable gases from a vessel to be maintained at sub-atmospheric pressure. The pirani and thermal-conductivity gauges are vacuum gauges used to measure the absolute pressure within a vacuum system (vacuum level), usually expressed in torr or Pa.
用于从容器中排出空气和不凝性气体以保持在亚大气压的泵。皮拉尼和热导率计是用于测量真空系统内绝对压力(真空水平)的真空计,通常用托或帕表示。
Quench hardening 淬火硬化 (1) Hardening suitable alpha-beta alloys (most often certain copper to titanium alloys) by solution treating and quenching to develop a martensitic-like structure. (2) In ferrous alloys, hardening by austenitizing and then cooling at a rate such that a substantial amount of austenite transforms to martensite.
(1)通过固溶处理和淬火硬化合适的α-β合金(通常是某些铜-钛合金),以形成类似马氏体的结构。(2)在铁合金中,通过奥氏体化硬化,然后以一定速度冷却,使大量奥氏体转变为马氏体。
Positive-displacement flow meter 容积式流量计 An instrument of high accuracy that determines volumetric flow rate by dividing the flowing fluid into successive fixed volumes, and measuring their times of passage through the meter.
一种高精度仪器,通过将流动的流体分成连续的固定体积并测量其通过流量计的时间来确定体积流量。
Altitude chamber 高空舱 (hypobaric chamber) A chamber in which conditions at different altitudes are simulated by a combination of appropriate pressures, temperatures and relative humidity.
(低压舱)通过适当的压力、温度和相对湿度的组合来模拟不同高度条件的舱室。
Hypoeutectoid alloy 亚共析合金 In an alloy system exhibiting a eutectoid, any alloy whose composition has an excess of base metal compared with the eutectoid composition, and whose equilibrium microstructure contains some eutectoid structure.
在呈现共析的合金系统中,与共析成分相比,其成分具有过量母材的任何合金,并且其平衡微观结构包含一些共析结构。
Screw pump 螺杆泵 A positive-displacement pump that uses one or more helical rotors rotating within a casing to transfer liquids or slurries.
一种容积式泵,使用一个或多个在外壳内旋转的螺旋转子输送液体或泥浆。
Heat-capacity rate (c) (Unit W/K) 热容率(c)(单位W/K) For fluid flow in a duct with mass flow rate ṁ, the product ṁC where C is the specific-heat capacity, at constant pressure (CP) in the case of a gas.
对于质量流量为ṁ的管道中的流体流动,乘积ṁC其中C是比热容,在气体的情况下为恒定压力(CP)。
Thermal analysis 热分析 A method for determining transformations in a metal by noting the temperatures at which thermal arrests occur. These arrests are manifested by changes in slope of the plotted or mechanically traced heating and cooling curves. When such data are secured under nearly equilibrium conditions of heating and cooling, the method is commonly used for determining certain critical temperatures required for the construction of equilibrium diagrams.
一种通过记录发生热阻的温度来确定金属转变的方法。这些阻力表现为绘制或机械追踪的加热和冷却曲线斜率的变化。当这些数据在加热和冷却的近似平衡条件下得到保证时,该方法通常用于确定构建平衡图所需的某些临界温度。
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。
Torque arm 扭力臂 A bar fixed at one end used to resist torque applied at the other, for example by an electric drill.
固定在一端的杆,用于抵抗施加在另一端的扭矩,如电钻。
Compressible flow 可压缩流动 A gas flow in which the Mach number M is sufficiently high for the gas density to change significantly. For air, this is when M > 0.3.
马赫数M高到足以使气体密度发生显着变化的气流。对于空气,这是当M>0.3时。
Thermodynamics laws 热力学定律 The zeroth, first, second, and third laws of thermodynamics.
热力学第零、第一、第二和第三定律。
British Standards Institution (BSI) 英国标准协会(BSI) The Institution in the UK responsible for the preparation and publication of standard specifications (British standards) for manufactured goods, their design, manufacture and testing.
负责为制成品及其设计、制造和测试制定和发布标准规范(英国标准)的英国机构。
Torque converter 变矩器 A turbomachine used for torque amplification consisting of an impeller, a turbine, and a reaction member. Applications include motor-vehicle transmissions.
用于扭矩放大的涡轮机,由叶轮、涡轮机和反作用构件组成。应用包括机动车变速器。
Fitted bolt 装配螺栓 A bolt with a plain unthreaded portion immediately beneath the head.
一种螺栓,其头部正下方有一个普通的无螺纹部分。
Crack-growth rate 裂纹增长速度 Rate of propagation of a crack through a material due to statically or dynamically applied load.
由于静态或动态施加的载荷,裂纹在材料中的扩展速率。
Congruent transformation 全等变换 An isothermal or isobaric phase change in which both of the phases concerned have the same composition throughout the process.
等温或等压相变,其中相关的两个相在整个过程中具有相同的成分。
Breaking stress 断裂应力 The stress at failure. Also known as rupture stress.
失效时的应力。也称为破裂应力。
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。
Toughness (Unit J/m²) 韧性(单位:J/m²) The ability of a metal to absorb energy and deform plastically before fracturing. 1. The ability of a material to resist crack initiation and propagation. 2. The ability of a material to absorb strain energy without fracturing.
金属在破裂前吸收能量和塑性变形的能力。1.材料抵抗裂纹萌生和扩展的能力。2.材料在不发生断裂的情况下吸收应变能的能力。
Elastic calibration device 弹性校准装置 A device for use in verifying the load readings of a testing machine consisting of an elastic member(s) to which loads may be applied, combined with a mechanism or device for indicating the magnitude (or a quantity proportional to the magnitude) of deformation under load.
一种用于验证试验机载荷读数的装置,由可施加载荷的弹性构件组成,与指示载荷下变形量(或与该量成比例的量)的机构或装置相结合。
Tyre 轮胎 A flexible ring-shaped cover mounted on a wheel rim that supports the weight of a vehicle, such as a motor vehicle, aircraft, or bicycle, and transmits power and torque to a road surface. Some pneumatic tyres are inflated directly, others have a separate inner tube that is inflated. For certain applications, solid tyres are used.
车轮罩安装在轮辋上的柔性环形罩,用于支撑车辆(如机动车、飞机或自行车)的重量,并将动力和扭矩传递到路面。有些充气轮胎是直接充气的,有些轮胎有单独的内胎充气。对于某些应用,使用实心轮胎。
Twist 扭转 The helix produced in a cylindrical component, such as a shaft, wire, tensioned cable, or rope, when one end is rotated relative to the other. Measured either as the number of turns per unit length, or by the helix angle (twist angle).
当一端相对于另一端旋转时,在圆柱形部件(如轴、钢丝、张紧电缆或绳索)中产生的螺旋。以每单位长度的圈数或螺旋角(扭曲角)测量。
Compression stroke 压缩冲程 The stroke in a reciprocating compressor or engine during which the working fluid is compressed.
往复式压缩机或发动机中工作流体被压缩的冲程。
Shoulder bolt 轴肩螺栓 A bolt for which the unthreaded cylindrical section between the thread and the head is of larger diameter than the threaded section, precisely machined to length and diameter and hardened
一种螺栓,其螺纹和头部之间的无螺纹圆柱段的直径大于螺纹段的直径,精确加工至长度和直径并硬化
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。
Barcol hardness test 巴氏硬度测试 An indentation test, similar to the Shore hardness test but using a pointed indentor with a flat tip, used to determine the hardness of such materials as rigid plastics and composites.
一种压痕测试,类似于肖氏硬度测试,但使用带有扁平尖端的尖头压头,用于确定硬质塑料和复合材料等材料的硬度。
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。
Materials selection 材料选择 The process of selecting the most suitable material for a particular application. In the case of solid materials, it involves assessment of candidate materials in terms of their physical properties (density, elastic moduli, fracture toughness, yield strength, hardness, fatigue resistance, coefficient of thermal expansion, thermal conductivity, resistance to thermal shock, creep resistance, corrosion resistance, radiation resistance, etc), and such factors as the function of the final product, its shape, method of manufacture, required tolerances, number to be made, ease of inspection and quality control, cost, and design methodology employed.
为特定应用选择最合适材料的过程。对于固体材料,它涉及根据其物理特性(密度、弹性模量、断裂韧性、屈服强度、硬度、抗疲劳性、热膨胀系数、导热系数、抗热冲击性、抗蠕变性、耐腐蚀性、抗辐射性等)评估候选材料,以及诸如最终产品的功能、其形状、制造方法、所需公差、制造数量、检查和质量控制的容易程度、成本和采用的设计方法等因素。
Turbomachine 涡轮机械 (rotodynamic machine) A machine in which there is a transfer of energy between a continuous stream of fluid and a component, called a rotor, rotating about a fixed axis. Fans and turbines (gas, hydraulic, steam, or wind) are turbomachines in which energy is transferred to the rotor, causing it to rotate. Pumps and compressors are turbomachines in which energy is transferred from the externally driven rotor to the fluid.
(旋转动力机器)在连续的流体流和绕固定轴旋转的部件(称为转子)之间进行能量传递的机器。风扇和涡轮机(燃气、液压、蒸汽或风力)是涡轮机械,其中能量传递到转子,使其旋转。泵和压缩机是涡轮机械,其中能量从外部驱动的转子传递到流体。
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。
Strain-hardening exponent (n value) 应变硬化指数(n值) The value n in the relationship σ = Kεn, where σ is the true stress, ε is the true strain, and K, the strength coefficient, is equal to the true stress at a true strain of 1.0. The strain hardening exponent is equal to the slope of the true stress/true strain curve up to maximum load, when plotted on log-log coordinates. The n-value relates to the ability of a sheet of material to be stretched in metalworking operations. The higher the n-value, the better the formability(stretchability). Also known as the strain-hardening coefficient.
关系式σ=Kεn中的值n,其中σ是真应力,ε是真应变,K是强度系数,等于真应变为1.0时的真应力。在对数坐标上绘制时,应变硬化指数等于真应力/真应变曲线的斜率,直到最大载荷。n值与一片材料在金属加工操作中拉伸的能力有关。n值越高,成形性(拉伸性)越好。也称为应变硬化系数。
Tensioner 张紧器 A hydraulic tool used to tighten a fastener by stretching it rather than by applying a substantial torque to the nut. After the tension has stretched the bolt or stud, the nut is run down against the joint with a modest torque, and the tensioner is disengaged from the fastener. The nut holds the stretch produced by the tensioner.
一种液压工具,用于通过拉伸紧固件而不是对螺母施加较大扭矩来拧紧紧固件。张力拉伸螺栓或螺柱后,以适当的扭矩将螺母向下压靠接头,张紧器与紧固件分离。螺母保持张紧器产生的拉伸。
Rockwell hardness number (HR) 洛氏硬度值(HR) A number derived from the net increase in the depth of impression in a Rockwell hardness test as the load on an indenter is increased from a fixed minor load to a major load and then returned to the minor load. Rockwell hardness numbers are always quoted with a scale symbol representing the penetrator, load, and dial used.
当压头上的载荷从固定的小载荷增加到大载荷,然后返回到小载荷时,洛氏硬度试验中压痕深度的净增加值。洛氏硬度值总是用刻度符号引用,表示所用的穿透器、载荷和刻度盘。
Milling 铣削 A machining process, typically for metals and plastics, in which a multi-tooth rotary cutter removes material to produce flat or profiled surfaces, slots, grooves, etc. Milling is a machining process in which metal is removed by a rotating multiple-tooth cutter; each tooth removes a small amount of metal with each revolution of the spindle. Because both workpiece and cutter can be moved in more than one direction at the same time, surfaces having almost any orientation can be machined.
一种加工工艺,通常用于金属和塑料,其中多齿旋转刀具去除材料以产生平坦或异形表面、槽、槽等。金属由旋转多齿刀具去除;主轴每转一圈,每个齿都会去除少量金属。因为工件和刀具可以同时在多个方向上移动,所以几乎可以加工任何方向的表面。
Cold working 冷加工 The plastic deformation of a metal, by rolling (cold rolling), drawing, forging (cold forging), etc. at a temperature well below its recrystallization temperature, which results not only in permanent shape change but also increase in strength and loss of ductility owing to work-hardening.
金属在远低于其再结晶温度的温度下通过轧制(冷轧)、拉拔、锻造(冷锻)等方式发生塑性变形,这不仅会导致永久的形状变化,还会增加强度并降低延展性由于加工硬化。
Archimedes Wave Swing 阿基米德波摆动 A machine for tidal-power energy generation consisting of two concentric, air-filled submerged cylinders. The inner lower cylinder is tethered to the ocean floor while the upper floater unit, which is closed at the top, moves up and down due to the variations in hydrostatic pressure caused by the wave motion. The relative movement of the two cylinders is used to generate electricity in which linear motion replaces the more common rotary motion of an electromagnetic generator.
一种用于潮汐能发电的机器,由两个同心的充气水下气缸组成。内部下部圆柱体系在海底,而顶部封闭的上部浮子单元由于波浪运动引起的静水压力变化而上下移动。两个气缸的相对运动用于发电,其中直线运动取代了电磁发电机更常见的旋转运动。
Load factor (F) 负载系数(F) The ratio between an increase in bolt tension and the external load which has caused the increase. Factors reflecting the probability of an increase in load in a shear joint. Used in load and resistant factor design.
螺栓张力增加与导致增加的外部载荷之间的比率。反映剪切接缝中荷载增加概率的系数。用于载荷和阻力系数设计。
Steam gauge 汽压表 A pressure gauge used to measure gauge pressure in a line, boiler, cylinder, or other device operating with steam.
一种压力表,用于测量管道、锅炉、汽缸或其他与蒸汽一起工作的装置中的表压。
Elastic strain energy 弹性应变能 The energy expended by the action of external forces in deforming a body elastically. Essentially, all the work performed during elastic deformation is stored as elastic energy, and this energy is recovered upon release of the applied force.
在外力作用下使物体弹性变形所消耗的能量。本质上,弹性变形过程中所做的所有功都以弹性能的形式存储,并且在释放所施加的力时恢复该能量。
J-integral J-积分 A mathematical expression describing a line or surface integral that encloses the crack front from one crack surface to the other, used to characterize the fracture toughness of a material having appreciable plasticity before fracture. The J-integral eliminates the need to describe the behavior of the material near the crack tip by considering the local stress-strain field around the crack front; JIc is the critical value of the J-integral required to initiate crack extension from a preexisting crack.
描述从一个裂纹表面到另一个裂纹正面的线或表面积分的数学表达式,用于表征断裂前具有可观塑性的材料的断裂韧性。J积分通过考虑裂纹前缘周围的局部应力应变场,无需描述裂纹尖端附近材料的行为;JIc是从先前存在的裂纹开始裂纹扩展所需的J积分的临界值。
Thermodynamic state 热力学状态 The condition of a system or working fluid according to its properties.
系统或工作流体根据其性质的状态。
Mechanical efficiency (η) 机械效率(η) 1. In general for a machine, the ratio of output work to input work. 2. For a compressor, the ratio of indicated power to shaft power; for a reciprocating engine or an expander, the ratio of shaft power to indicated power.
1.一般而言,机器的输出功与输入功之比。2.对于压缩机,指示功率与轴功率之比;对于往复式发动机或膨胀机,轴功率与指示功率之比。
Minimum load (Pmin) 最小负载(Pmin) In fatigue, the least algebraic value of applied load in a cycle.
在疲劳中,循环中施加载荷的最小代数值。
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
Centrifugal fan 离心风机 A machine with a rotor consisting of a number of blades mounted around a hub and used for moving air or other gases. The gas enters the rotor axially and is discharged radially at increased pressure.
一种带有转子的机器,转子由安装在轮毂周围的许多叶片组成,用于移动空气或其他气体。气体轴向进入转子并在增加的压力下径向排出。
Belt furnace 带式炉 A continuous-type furnace which uses a mesh-type or cast-link belt to carry parts through the furnace.
一种连续式炉,它使用网状或铸造链带将零件运送通过炉子。
Permanent set 永久变形 The deformation or strain remaining in a previously stressed body after release of load.
释放荷载后,先前受力物体中剩余的变形或应变。
Oxidative wear 氧化磨损 A type of wear resulting from the sliding action between two metallic components that generates oxide films on the metal surfaces. These oxide films prevent the formation of a metallic bond between the sliding surfaces, resulting in fine wear debris and low wear rates.
由两个金属部件之间的滑动作用导致的一种磨损,在金属表面上产生氧化膜。这些氧化膜防止在滑动表面之间形成金属结合,导致细磨屑和低磨损率。
Interrupted quenching 间断淬火 A quenching procedure in which the workpiece is removed from the first quench at a temperature substantially higher than that of the quenchant and is then subjected to a second quenching system having a different cooling rate than the first.
在该淬火过程中,工件在显著高于淬火剂的温度下从第一次淬火中取出,然后经受具有不同于第一次淬火的冷却速率的第二次淬火系统。
Swift cup test 斯威夫特杯测试 A simulative cupping test in which circular blanks of various diameters are clamped in a die ring and deep drawn into cups by a flat-bottomed cylindrical punch.
一种模拟拔杯试验,将不同直径的圆形坯料夹紧在模环中,并用平底圆柱冲头将其深拉入杯中。
Ductile cast iron 球墨铸铁 A cast iron that has been treated while molten with an element such as magnesium or cerium to induce the formation of free graphite as nodules or spherulites, which imparts a measurable degree of ductility to the cast metal. Also known as nodular cast iron, spherulitic graphite cast iron and SG iron.
一种铸铁,在熔融时用镁或铈等元素进行处理,以诱导游离石墨形成为球粒或球晶,从而赋予铸造金属可测量的延展性。又称球墨铸铁、球晶石墨铸铁和SG铸铁。
Condenser 冷凝器 A heat exchanger in which a substance is changed from its vapour phase to its liquid phase by reducing its temperature to below the saturation temperature.
一种热交换器,通过将物质的温度降低到饱和温度以下,将其从气相变为液相。
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。
Martempering 淬火 (1) A hardening procedure in which an austenitized ferrous workpiece is quenched into an appropriate medium whose temperature is maintained substantially at the Ms of the workpiece, held in the medium until its temperature is uniform throughout–but not long enough to permit bainite to form–and then cooled in air. The treatment is frequently followed by tempering. (2) When the process is applied to carburized material, the controlling Ms temperature is that of the case. This variation of the process is frequently called marquenching.
(1)一种淬火工艺,将奥氏体化铁质工件淬火到适当的介质中,该介质的温度基本保持在工件的Ms,保持在该介质中直到其温度在整个过程中均匀,但不足以形成贝氏体,然后在空气中冷却。处理后经常进行回火。(2) 当该工艺应用于渗碳材料时,控制Ms温度与实际情况相同。这个过程的变化经常被称为淬火。
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。
Positive-displacement compressor 容积式压缩机 Any type of compressor, including piston and rotary-screw types, that delivers a fixed volume of gas at high pressure per unit time. A positive-displacement pump delivers a fixed volume of fluid, usually a liquid, per unit time.
任何类型的压缩机,包括活塞式和旋转螺杆式,在单位时间内以高压输送固定体积的气体。容积泵每单位时间输送固定体积的流体,通常为液体。
Cavitation 空蚀空化 The formation of vapour- or gas-filled cavities in a liquid due to reduction of the local pressure, often due to acceleration of the fluid, such as in flow through a convergent nozzle. If there is no dissolved gas in the liquid, vaporous cavitation occurs when the pressure falls below the saturated vapour pressure. If the bubbles are formed due to high temperature, the process is termed boiling. If there is dissolved gas, gaseous cavitation occurs due to pressure reduction, temperature increase, or diffusion (degassing). At the tips of marine propellers and in hydraulic machinery, the collapse of cavitation bubbles can cause noise and vibration and lead to surface damage in the form of pitting.
由于局部压力降低而在液体中形成充满蒸汽或气体的空腔,通常原因是流体的加速,例如收敛喷嘴的流动。如果液体中没有溶解气体,当压力降至饱和蒸汽压力以下时,会发生蒸汽空化。如果气泡是由于高温形成的,则该过程称为沸腾。如果存在溶解气体,则由于压力降低、温度升高或扩散(脱气),会发生气穴。在船用螺旋桨尖端和液压机械中,空化气泡的破裂可能会引起噪音和振动,并导致以点蚀形式出现的表面损坏。
Chafing fatigue 磨损疲劳 Fatigue damage initiated in a surface damaged by rubbing against another body.
因与另一个物体摩擦而损坏的表面引起的疲劳损坏。
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。
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。
Millimetre of water 毫米水柱 A non-SI unit of pressure equal to the pressure exerted by a vertical column of water 1 mm high. Approximately equal to 9.81 Pa.
一种非SI压力单位,等于1毫米高的垂直水柱施加的压力。大约等于9.81Pa。
Elastic energy 弹性能 The amount of energy required to deform a material within its elastic range of behavior, neglecting small heat losses due to internal friction. The energy absorbed by a specimen per unit volume of material contained within the gage length being tested. It is determined by measuring the area under the stress-strain curve up to a specified elastic strain. See also modulus of resilience and strain energy.
材料在其弹性行为范围内变形所需的能量,忽略因内耗引起的小热损失。试样在被测标距内每单位体积材料吸收的能量。它是通过测量应力-应变曲线下达到规定弹性应变的面积来确定的。另见弹性模量和应变能。
Anneal to temper 退火回火 A final partial anneal that softens a cold worked nonferrous alloy to a specified level of hardness or tensile strength.
将冷加工的有色金属合金软化到规定的硬度或抗拉强度水平的最终局部退火。
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。
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。
Finish annealing 精制退火 A subcritical annealing treatment applied to cold-worked low- or medium-carbon steel. Finish annealing, which is a compromise treatment, lowers residual stresses, thereby minimizing the risk of distortion in machining while retaining most of the benefits to machinability contributed by cold working. Compare with final annealing.
适用于冷加工低碳钢或中碳钢的亚临界退火处理。与最终退火相比,精加工退火是一种折衷处理,可降低残余应力,从而最大限度地降低加工中的变形风险,同时保留冷加工对可加工性的大部分好处。
Lubricant 润滑剂 Any substance interposed between two surfaces for the purpose of reducing the friction or wear between them.
为了减少两个表面之间的摩擦或磨损而置于两个表面间的任何物质。
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。
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。
Pump A machine designed to cause a liquid, gas, vapour, or slurry to flow due to the reciprocating motion of pistons, rotation of vanes, or rotation of an impeller.
通过活塞的往复运动、叶片的旋转或叶轮的旋转而使液体、气体、蒸汽或泥浆流动的机器。
U-tube U型管 A device consisting of two vertical tubes connected at either the top or bottom by a length of tubing such that a U-shape is formed.
由两个垂直管组成的装置,在顶部或底部通过一段管子连接,形成U形。
Pitting 点蚀 In tribology, a type of wear characterized by the presence of small, sharp surface cavities formed by processes such as fatigue, local adhesion, wear, corrosion, or cavitation.
在摩擦学中的一种磨损,其特征是存在由疲劳、局部粘附、磨损、腐蚀或空穴等过程形成的小而尖锐的表面空穴。
Closed-die forging 闭模锻造 The forming of a workpiece by compression within a pair of dies having the female form of the component to be manufactured (closed dies), superfluous metal being expelled as flash where the dies meet.
在一对具有待制造部件的阴模的模具(闭模)内通过压缩形成工件,多余的金属在模具相遇处作为飞边排出。
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。
Stress corrosion 应力腐蚀 (stress-corrosion cracking) Corrosion failure accelerated by local stresses (particularly tensile) which enhance cracking in both monotonic and fatigue loading.
(应力腐蚀开裂)局部应力(特别是拉伸应力)加速的腐蚀失效,该局部应力在单调载荷和疲劳载荷下都会增强开裂。
Lockbolt 锁紧螺栓 A fastener which bears a superficial resemblance to a bolt, but which engages a collar (instead of a nut) with annular grooves (instead of threads). The collar is swaged over the grooves on the male fastener to develop preload.
表面上类似于螺栓的紧固件,但与环槽(而不是螺纹)接合的轴环(而不是螺母)。套环在阳紧固件上的凹槽上锻造,以产生预紧力。
Nano machining 纳米加工 The machining of silicon chips typically less than 1 nm thick.
硅芯片的加工通常小于1nm厚。
Heat (q, Q) (Unit J) 热量(q, Q)(单位J) A form of energy that is transferred across the boundary of a system at one temperature to another system (or the surroundings) at a different temperature by virtue of the temperature difference between them. Heat can be identified only as it crosses the boundary. A body can never be said to contain heat which is thus a transient phenomenon.
一种能量形式,由于它们之间的温差在一个温度下通过系统边界传递到另一个温度不同的系统(或环境)。只有当热量穿过边界时才能识别。一个物体不能说永远含有热量,这是一种瞬态现象。
Tribology 摩擦学 The science and technology concerned with interacting surfaces in relative motion.
与相对运动中相互作用的表面有关的科学和技术。
Tooth lock washers 带齿锁紧垫圈 These washers serve to lock fasteners, such as bolts and nuts, to the component parts of an assembly, or increase the friction between the fasteners and the assembly. They are designated in a manner similar to helical spring lock washers, and are available in carbon steel.
这些垫圈用于将紧固件(如螺栓和螺母)锁定到组件的零部件上,或增加紧固件与组件之间的摩擦力。它们的设计方式类似于螺旋弹簧锁紧垫圈,可采用碳钢。
Mohs hardness test 莫氏硬度测试 A scratch hardness test for determining comparative hardness using 10 standard minerals—from talc (the softest) to diamond (the hardest).
刮擦硬度测试,用于使用从滑石(最软)到钻石(最硬)的10种标准矿物测定比较硬度。
Radiosity (J) (Unit W/m²) 辐射度(J)(单位W/m²) The total radiation leaving a given surface per unit area, including emitted, reflected, and transmitted radiation.
每单位面积离开给定表面的总辐射,包括发射、反射和透射辐射。
Overheating 过热 Heating a metal or alloy to such a high temperature that its properties are impaired. When the original properties cannot be restored by further heat treating, by mechanical working, or by a combination of working and heat treating, the overheating is known as burning.
将金属或合金加热至其性能受损的高温。当通过进一步热处理、机械加工或加工与热处理的组合无法恢复原始性能时,过热称为燃烧。
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。
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。
Surface treatment 表面处理 Any process, including chemical, electrochemical, mechanical, and thermal, designed to protect a surface against corrosion and wear or to alter its mechanical properties.
任何旨在保护表面免受腐蚀和磨损或改变其机械性能的工艺,包括化学、电化学、机械和热处理。
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。
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。
Waste heat 废热 1. Heat generated by internal-combustion engines, gas turbines, electrical generators, electrical equipment, and industrial processes that is not used directly but is expelled to the environment, often in hot flue or exhaust gases. 2. Heat generated from waste
1.内燃机、燃气轮机、发电机、电气设备和工业过程产生的热量,这些热量不是直接使用的,而是通过热烟气或废气排放到环境中。2.废物产生的热量
Heat tinting 热着色 Coloration of a metal surface through oxidation by heating to reveal details of the microstructure.
通过加热氧化使金属表面着色,以揭示微观结构的细节。
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。
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。
Rated power (Unit kW or hp) 额定功率(单位:千瓦或马力) (rated capacity, rated horsepower) The maximum power output that can be sustained continuously for any power-producing machine or system, such as an engine or a power plant.
(额定容量、额定马力)任何发电机器或系统(如发动机或发电厂)可连续维持的最大功率输出。
Free machining 易切削 The property that makes machining easy because of the forming of small chips, a characteristic imparted to steel by sulfur, etc.
由于形成小切屑而使加工变得容易的特性,比如硫赋予钢的特性,等等。
Thermochemical treatment 热化学处理 Heat treatment carried out in a medium suitably chosen to produce a change in the chemical composition of the object by exchange with the medium.
在适当选择的介质中进行热处理,以通过与介质交换产生物体化学成分的变化。
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。
Serrations 锯齿 A row of notches or tooth-like projections on an edge or surface. On an engineering drawing, serrations on the surface of a circular component are shown over about 60° of arc.
边缘或表面上的一排凹口或齿状突起。在工程图纸上,圆形部件表面的锯齿超过约60°的圆弧。
Dynamic load (Unit N) 动态负载(单位N) 1. Loading of a component or structure by a moving object whose point of application changes with time, e.g. the live load of a train passing over a bridge. 2. A load applied to a particular part of a component or structure in a short time interval.
1. 应用点随时间变化的移动物体对部件或结构的加载,例如通过桥梁的火车的活荷载。2. 在短时间内施加到部件或结构的特定部分的载荷。
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。
Nanoparticles 纳米颗粒 Particles with dimensions of order 1 nm which have either been introduced into microstructures for reinforcement or are present as impurities.
尺寸为1nm级的颗粒,其已被引入微结构中用于增强或作为杂质存在。
Dead load (Unit N) 静载(单位N) A load on a component or structure that is steady with time, e.g. the self-weight of a bridge.
部件或结构上随时间稳定的载荷,例如桥梁的自重。
Acoustic droplet ejection 声液滴喷射 The ejection of small droplets from the surface of a liquid that results from focusing high-intensity ultrasound near the surface.
由于在表面附近聚焦高强度超声波而从液体表面喷射出小液滴。
Available draught (Unit Pa) 可用通风量(单位Pa) The reduced pressure of combustion gases in a furnace or boiler, either forced or due to the buoyancy of hot gases, which is used to draw in combustion air and remove products of combustion.
炉子或锅炉中燃烧气体的压力降低,无论是强制还是由于热气体的浮力,用于吸入燃烧空气并去除燃烧产物。
Compression fitting 压缩接头 A screwed joint for pipework made resistant to leakage by permanent deformation of a closely-fitting ring, called a ferrule or olive, on tightening.
一种用于管道的螺纹接头,通过紧密配合的环(称为套圈或橄榄形)在拧紧时的永久变形来防止泄漏。
Stainless steels 不锈钢 Iron-base alloys that are highly resistant to corrosion in many environments. The predominant alloying element is chromium, which, like iron at room temperature, has BCC crystal structure. Corrosion resistance by passivation is achieved by the formation of chromium oxide on the steel surface. Nickel, which has FCC crystal structure, is another important addition for some steels. Other additions used to enhance properties include manganese, molybdenum, niobium, and titanium. There are several classes of stainless steel.
在许多环境中具有高度耐腐蚀性的铁基合金。主要的合金元素是铬,与室温下的铁一样,铬具有BCC晶体结构。钝化抗腐蚀性是通过在钢表面形成氧化铬来实现的。具有FCC晶体结构的镍是某些钢的另一种重要添加剂。其他用于增强性能的添加剂包括锰、钼、铌和钛。不锈钢的种类有好几种。
Ductile fracture 韧性断裂 Fracture characterized by tearing of metal accompanied by appreciable gross plastic deformation and expenditure of considerable energy. A fracture of a component or structure which is preceded by extensive ductile deformation so that the broken pieces cannot be re-fitted to regain the original size and shape of the component or structure.
以金属撕裂为特征的断裂,伴随着明显的总塑性变形和相当大的能量消耗。一种部件或结构的断裂,在断裂前会发生大范围的延性变形,从而使断裂的碎片无法重新装配以恢复部件或结构原来的尺寸和形状。
Turbine flow meter 涡轮流量计 (axial flow meter, propeller meter) An in-line flow meter in which the rotation speed N of a propeller or rotor is a measure of the mass flowrate ṁ. Calibration is always necessary but with appropriate design ṁ is closely proportional to N over a wide range.
(轴向流量计、螺旋桨流量计)一种串联流量计,其中螺旋桨或转子的转速N是质量流量的测量值ṁ. 校准总是必要的,但需要适当的设计ṁ在很宽的范围内与N成正比。
Sample average 样本平均值 The sum of all the observed values in a sample divided by the sample size. It is a point estimate of the population mean. Also known as arithmetic mean.
样本中所有观察值的总和除以样本大小。它是总体平均值的点估计。也称为算术平均值。
Composite material 复合材料 (composite structure) A general term used of two or more materials or structures acting in combination (e.g. concrete, reinforced concrete, filamentreinforced polymers, laminated materials, particulate-reinforced materials, flitched beams), resulting in values of strength, stiffness, or toughness greater than the base matrix material alone.
(复合结构)用于组合作用的两种或多种材料或结构的通用术语(例如混凝土、钢筋混凝土、纤维增强聚合物、层压材料、颗粒增强材料、切割梁),从而产生强度、刚度或韧性值大于单独的基体材料。
Dew point 压力露点 The temperature and pressure at which a gas begins to condense to a liquid.
气体开始凝结成液体的温度和压力。
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。
Induction heating 感应加热 Heating by combined electrical resistance and hysteresis losses induced by subjecting a metal to the varying magnetic field surrounding a coil carrying alternating current.
通过将金属置于承载交流电的线圈周围的变化磁场中而引起的电阻和磁滞损耗的组合加热。
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。
Torsional angle (ϕ) 扭转角(ψ) (Unit ° or rad) The angular deflexion between two locations on a straight bar subjected to a torque.
(单位为°或rad)受扭矩作用的直杆上两个位置之间的角偏转。
Fracture 断裂 (rupture) The separation of materials, components, or structures into two or more parts by the propagation of one or more cracks. Cracking may be globally elastic (brittle) or accompanied by varying degrees of plasticity (ductile).
(断裂)通过一个或多个裂纹的扩展将材料、部件或结构分离成两个或更多部分。裂纹可能是整体弹性(脆性)或伴有不同程度的塑性(延性)。
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。
Continuous precipitation 连续沉淀 Precipitation from a supersaturated solid solution in which the precipitate particles grow by longrange diffusion without recrystallization of the matrix. Continuous precipitates grow from nuclei distributed more or less uniformly throughout the matrix. They usually are randomly oriented, but may form a Widmanstätten structure.
来自过饱和固溶体的沉淀,其中沉淀颗粒通过长程扩散生长而无需基质再结晶。连续析出物从在整个基体中或多或少均匀分布的核生长而来。它们通常是随机取向的,但可能形成魏氏结构。
Transverse strain 横向应变 Linear strain in a plane perpendicular to the loading axis of a specimen.
垂直于试样加载轴的平面内的线性应变。
Honing 珩磨 Honing is a controlled, low-speed sizing and surface-finishing process in which stock is removed by the shearing action to the bonded abrasive grains of a honing stone, or stick. Finish polishing of surfaces and cutting edges in which very fine abrasive powders, such as rouge, are employed. Honing is usually applied to cylindrical surfaces and lapping to flat, but the usage is not consistent.
珩磨是一种受控的低速尺寸和表面精加工工艺,其中通过对珩磨石或棒的粘结磨粒的剪切作用去除原料。表面和切削刃的精抛光,其中使用了非常细的研磨粉,例如胭脂。珩磨通常用于圆柱面,研磨至平面,但用法并不一致。
Fillet 圆角 Transition region between bolt head and shank, or between other changes in diameter.
螺栓头和螺栓杆之间的过渡区域,或其他直径变化之间的过渡区域。
Wind pressure (Unit Pa) 风压(单位Pa) The dynamic pressure associated with the wind. The static pressure of the wind is the atmospheric pressure.
与风相关的动态压力。风的静压是大气压。
Spring 弹簧 An elastic component which stores mechanical energy and exerts a force when deformed. The slope of the curve of applied force F to the deflexion of a spring x, dF/dx, is termed the spring rate or spring modulus k with unit N/m. For a linear spring, the F(x) curve is proportional and k is called the spring constant. An elastic device which yields under stress or pressure but returns to its original state or position when the stress or pressure is removed.
储存机械能并在变形时施加力的弹性部件。作用力F与弹簧x偏转的曲线斜率dF/dx称为弹簧率或弹簧模量k,单位为N/m。对于线性弹簧,F(x)曲线成比例,k称为弹簧常数。一种弹性装置,在应力或压力下屈服,但在应力和压力消除后恢复到其原始状态或位置。
Tension testing 张力测试 A method of determining the behavior of materials subjected to uniaxial loading, which tends to stretch the metal. A longitudinal specimen of known length and diameter is gripped at both ends and stretched at a slow, controlled rate until rupture occurs. Also known as tensile testing.
一种确定材料在单轴载荷下的行为的方法,这种载荷倾向于拉伸金属。将已知长度和直径的纵向试样夹持在两端,并以缓慢、受控的速率拉伸,直到发生断裂。也称为拉伸测试。
Slip 滑落 Plastic deformation by the irreversible shear displacement (translation)of one part of a crystal relative to another in a definite crystallographic direction and usually on a specific crystallographic plane. Sometimes called glide.
晶体的一部分在一定的晶体学方向上相对于另一部分的不可逆剪切位移(平移)引起的塑性变形,通常在特定的晶体主义平面上。有时被称为滑翔。
Abelian group 阿贝尔群 Property of a group of elements associated with a binary operation. In an Abelian group, the group elements commute under the binary operation. If a and b are any two group elements and if the (+) sign denotes the binary operation, then, for an Abelian group,
与二元运算相关的一组元素的属性。在阿贝尔群中,群元素在二元运算下交换。如果a和b是任意两个群元素并且(+)符号表示二元运算
Safety valve (safety-relief valve) 安全阀(安全泄压阀) A mechanical valve, fitted by law to all pressure vessels (e.g. steam boilers), which opens to prevent the internal pressure exceeding the maximum design value for that vessel. The valve closes again once the pressure reduces to a safe level.
根据法律安装在所有压力容器(如蒸汽锅炉)上的机械阀,其打开以防止内部压力超过该容器的最大设计值。一旦压力降至安全水平,阀门将再次关闭。
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。
Supercharging 增压 The process of increasing the mass flow rate of air (or air/fuel mixture) into the cylinder(s) of a piston engine using a compressor driven from the crankshaft (the supercharger). The power output is increased compared with a naturally-aspirated engine of the same capacity. The process also increases the air pressure and density to greater than ambient. In the past, most superchargers were mechanically driven from the engine’s crankshaft, but these have been largely superseded by turbochargers.
使用由曲轴(增压器)驱动的压缩机增加进入活塞式发动机气缸的空气(或空气/燃料混合物)质量流率的过程。与相同容量的自然吸气发动机相比,功率输出增加。该过程还将空气压力和密度增加到大于环境压力和密度。在过去,大多数增压器都是由发动机曲轴机械驱动的,但这些增压器在很大程度上已被涡轮增压器所取代。
Tensiometer 张力计 An instrument used to measure surface tension.
用来测量表面张力的仪器。
Secondary hardening 二次硬化 The process whereby some low-alloy steels, quenched to produce martensite, produce fine precipitates when tempered above 550°C, which inhibit dislocation motion and reverse the trend towards lower strength at higher tempering temperatures.
某些低合金钢经淬火产生马氏体,在550°C以上回火时产生细小沉淀的过程,这抑制了位错运动,扭转了在较高回火温度下强度降低的趋势。
Pitch diameter 中径 For screw threads, the diameter of an imaginary cylinder, the surface of which would pass through the threads at such points that would make the width of the groove and width of the land equal to one half the pitch.
对于螺纹,指一个假想圆柱体的直径,其表面将在使凹槽宽度和焊盘宽度等于螺距一半的点穿过螺纹。
Absorptance 吸收率 (absorptivity, absorption coefficient, α) The fraction of radiant flux incident on a surface that is absorbed by the surface. The term also applies to absorption of radiation by a volume of fluid. For a semi-transparent surface, α + ρ + τ = 1, where ρ is the reflectance and τ is the transmittance.
(吸收率,吸收系数,α)入射到表面的辐射通量被表面吸收的部分。该术语也适用于一定体积的流体对辐射的吸收。对于半透明表面,α+ρ+τ=1,其中ρ是反射率,τ是透射率。
Humidify 加湿 To add water vapour to air or another gas to increase its humidity.
将水蒸气添加到空气或其他气体中以增加其湿度。
Carbon potential 碳势 A measure of the ability of an environment containing active carbon to alter or maintain, under prescribed conditions, the carbon level of the steel. Note: In any particular environment, the carbon level attained will depend on such factors as temperature, time, and steel composition.
衡量含有活性碳的环境在规定条件下改变或保持钢的碳含量的能力。注意:在任何特定环境中,所达到的碳含量将取决于温度、时间和钢成分等因素。
Torsion-bar suspension 扭杆悬架 A type of motor-vehicle suspension in which one end of a torsion bar is rigidly fixed to the chassis while the other carries a lever to which are attached the components that carry a wheel. In a torsion-beam suspension, a beam connects the wheels on either side of the vehicle.
一种汽车悬架,其中扭力杆的一端刚性固定在底盘上,而另一端带有一个杠杆,杠杆上连接着承载车轮的部件。在扭转梁悬架中,梁连接车辆两侧的车轮。
Working stress (Unit Pa) 工作应力(单位Pa) The stress under which a component or structure is designed to operate under normal conditions.
部件或结构设计为在正常条件下运行的应力。
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。
Reproducibility 再现性 A term used to describe test-result variability associated with specifically defined components of variance obtained both from within a single laboratory and between laboratories.
一个术语,用于描述与从单个实验室内和实验室之间获得的具体定义的方差分量相关的测试结果可变性。
Second (s) 秒(s) The SI base unit of time equal to 9 192 631 770 times the period of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom.
SI基时间单位等于9192631770倍的辐射周期,对应于铯-133原子基态的两个超精细能级之间的跃迁。
Translational joint 平移铰 A robot joint where the controlled variable is straight line movement.
控制变量为直线运动的机器人关节。
Centre of pressure 压力中心 1. The location, on an aerofoil or other body that develops lift, of the resultant lift force. 2. The location, on a surface submerged in a liquid, of the resultant force due to the pressure acting on the surface. Because hydrostatic pressure increases with depth, the centre of pressure is generally below the centroid of the surface.
1.在产生升力的机翼或其他物体上,合成升力的位置。2.在浸没在液体中的表面上,由于作用在表面上的压力而产生的合力的位置。由于静水压力随深度增加,压力中心通常低于表面质心。
Thumb screw 蝶形螺钉 A type of screw having a winged or knurled head for turning by hand when a quick and light clamping effect is desired.
一种螺钉,具有翼形或滚花头,当需要快速、轻夹紧效果时,可手动转动。
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。
Transmissibility 传递率 The ratio of the transmitted force to the disturbing force for a system subjected to a vibratory disturbance. The ratio may also be defined in terms of displacements, velocities, or accelerations.
受到振动干扰的系统的传递力与干扰力之比。该比率也可以用位移、速度或加速度来定义。
Tap wrench 螺丝攻扳手 A lever with an adjustable square hole at its centre into which is fitted the shank of a tap so that torque can be applied to cut a thread.
一种杠杆,其中心有一个可调节的方孔,丝锥柄安装在该孔中,以便施加扭矩以切断螺纹。
Rockwell superficial hardness test 洛氏表面硬度试验 Same as Rockwell hardness test, except that smaller minor and major loads are used.
与洛氏硬度测试相同,只是使用较小的次要载荷和主要载荷。
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。
Breaking load (Unit N) 断裂负荷(单位N) The load applied at some point to a component or structure which leads to fracture. The breaking stress (breaking strength) is the average stress at which a member breaks, given by the breaking load divided by the area over which it acts.
在某个点施加到导致断裂的部件或结构的载荷。断裂应力(断裂强度)是构件断裂时的平均应力,由断裂载荷除以其作用的面积给出。
Atomizing humidifier 雾化加湿器 A humidifier that functions by spraying fine droplets of water into an airstream.
一种加湿器,通过将细小的水滴喷射到气流中来发挥作用。
Stress relaxation 应力松弛 The slow decrease in stress level within a part (e.g., a bolt) which is heavily loaded under constant deflection conditions. A ‘‘cousin’’ to creep, which is a slow change in geometry under constant stress conditions. The time-dependent decrease in stress in a solid under constant strain at constant temperature due to creep. The stress-relaxation behavior of a metal is usually shown in a stress-relaxation curve.
在恒定挠曲条件下,零件(如螺栓)内的应力水平缓慢降低,该零件承受重荷载。蠕变的“表亲”,是在恒定应力条件下几何结构的缓慢变化。在恒定温度下,由于蠕变,固体在恒定应变下的应力随时间变化的减小。金属的应力松弛行为通常显示在应力松弛曲线中。
Delamination 分层 A mode of failure of composite materials, including radial-ply tyres, in which the layers separate due to repeated cyclic loading, impact, or weak bonding.
复合材料的一种失效模式,包括子午线轮胎,其中层由于重复的循环载荷、冲击或弱粘合而分离。
Brake lining 制动衬片 The replaceable friction material that covers a brake shoe in an internally expanding brake.
在内膨胀制动器中覆盖制动的可更换摩擦材料。
Working load (Unit N) 工作负荷(单位:N) The tension in a bolt in use; tension produced by a combination of Residual preload and a portion (usually) of any External load. The Joint diagram is usually used to predict the approximate working load a fastener will see in service. The load under which a component or structure is designed to operate under normal conditions.
螺栓在使用中的张力;残余预载荷和部分(通常)任何外部载荷的组合产生的张力。连接图通常用于预测紧固件在使用中的近似工作载荷。部件或结构设计为在正常条件下运行的荷载。
Minimum material condition 最小材料条件 (minimum metal condition) The situation where the volume of a manufactured component corresponds to the lower limit of all toleranced external dimensions and to the upper limit for all internal dimensions.
(最小金属条件)制造部件的体积对应于所有公差外部尺寸的下限和所有内部尺寸的上限的情况。
PSI (pounds per square inch) PSI(磅/平方英寸) Pressure measurement. Psia (pounds per square inch absolute) measures actual pressure with no allowance for atmospheric pressure. Psig (pounds per square inch gauge) measures pressure with the gauge set to zero (0) at atmospheric pressure (14.7 psia). In other words psig = psia – 14.7.
压力测量。Psia(绝对磅/平方英寸)测量实际压力,不考虑大气压力。Psig(磅/平方英寸表压)在大气压(14.7 psia)下,将表压设置为零(0)时测量压力。换句话说,psig=psia–14.7。
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。
Total combustion air (Unit kg/s) 总燃烧空气(单位:kg/s) 1. The combination of the stoichiometric flow of air required for combustion together with any excess air. 2. The flow of fresh air into a boiler plus any flue gas recirculated.
1.燃烧所需的化学计量空气流与任何过量空气的组合。2.进入锅炉的新鲜空气流加上再循环的任何烟气。
Carbon restoration 碳修复 Replacing the carbon lost in the surface layer from previous processing by carburizing this layer to substantially the original carbon level. Sometimes called recarburizing.
通过将该层渗碳到基本上原始的碳水平来替换先前处理中在表面层中损失的碳。有时称为再碳化。
British thermal unit (BTU, Btu) 英热单位(BTU,Btu) An obsolete (non-SI) imperial unit of energy defined as the energy required to raise the temperature of one pound of pure water at 68°F by 1°F. The conversion to SI is 1 Btu = 1.055 056 × 103 J.
一种已被淘汰的(非SI)英制能量单位,定义为将68°F的一磅纯水的温度升高1°F所需的能量。转换为SI为1Btu=1.055056×103J。
Celsius 摄氏度 The temperature scale based on the freezing point of water (0ºC) and the boiling point of water (100ºC). The interval between these points is divided into 100 degrees. The scale was devised by Anders Celsius.
基于水的冰点(0ºC)和水的沸点(100ºC)的温标。这些点之间的间隔被划分为100度。这个比例是由安德斯·摄氏设计的。
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。
Uniform strain 均匀应变 The strain occurring prior to the beginning of localization of strain (necking); the strain to maximum load in the tension test.
在应变局部化(颈缩)开始之前发生的应变;拉伸试验中最大载荷的应变。
Stroke 一击 1. (stroke length) (Unit m) The linear distance between top dead centre and bottom dead centre of a piston in a reciprocating engine or mechanism. 2. The movement of a piston or plunger in a reciprocating machine to execute a particular function; for example, the exhaust stroke of an engine in which the exhaust gases are expelled from a cylinder.
1.(冲程长度)(单位:m)往复式发动机或机构中活塞上止点和下止点之间的线性距离。2.活塞或柱塞在往复式机器中执行特定功能的运动;例如发动机的排气冲程,其中排气从气缸中排出。
Cohesive strength 内聚强度 (Unit Pa) A theoretical fracture strength for solids based on interatomic forces, approximately equal to E/10 where E is Young’s modulus.
(单位Pa)基于原子间力的固体理论断裂强度,大约等于E/10,其中E是杨氏模量。
Corrosion fatigue 腐蚀疲劳 Cracking produced by the combined action of repeated or fluctuating stress and a corrosive environment at lower stress levels or fewer cycles than would be required in the absence of a corrosive environment.
由重复或波动的应力和腐蚀环境的联合作用产生的开裂,其应力水平低于没有腐蚀环境时所需的应力水平或循环次数更少。
Pitch (Unit m) 间距(单位:m) 1. In a cascade of identical turbine or compressor blades, the distance between successive blades measured parallel to the leading edges. 2. For a screw thread, the distance between adjacent thread forms measured parallel to the thread axis. 3. For an aircraft, the vertical relationship between the nose and the horizon. The pitch axis is an axis in the plane of the wings of an aircraft, perpendicular to the centreline, about which the aircraft rotates. Pitch motion is the corresponding up or down movement of the aircraft nose. Pitch attitude is the angle between the centreline of an aircraft and the horizontal. The angle is positive when the nose is above its position when the centreline is horizontal.
1.在相同涡轮或压缩机叶片的叶栅中,平行于前缘测量的连续叶片之间的距离。2.对于螺纹,平行于螺纹轴线测量的相邻螺纹形状之间的距离。3.对于飞机,机头和水平线之间的垂直关系。俯仰轴是飞机机翼平面内垂直于中心线的轴,飞机绕中心线旋转。俯仰运动是飞机机头的相应向上或向下运动。俯仰姿态是飞机中心线与水平线之间的角度。当中心线水平时,当机头高于其位置时,角度为正。
Fillet radius 圆角半径 Concave junction at two intersecting surfaces of a fastener. Often used to describe the junction between the head and the  shank of a threaded fastener (under head fillet).
在紧固件的两个相交表面处的凹形接合处。通常用于描述螺纹紧固件的头部和柄部之间的连接处(头部圆角下方)。
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。
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。
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。
Autonomous energy system 自主能源系统 (stand-alone energy system) A sole source of electricity, usually small-scale, for applications remote from a grid, especially with energy storage in the system. Hydroelectric, photovoltaic, wind-power and other renewable systems are well suited to stand-alone applications.
(独立能源系统)一种唯一的电力来源,通常是小规模的,用于远离电网的应用,尤其是系统中的能量存储。水电、光伏、风力和其他可再生能源系统非常适合独立应用。
Engine 引擎 A machine that converts energy, including the chemical energy in a fuel and electrical energy, into mechanical energy, usually to produce power delivered through a rotating shaft or thrust. Examples include internal-combustion engines, gas and steam turbines, rocket engines, electric, hydraulic and pneumatic motors.
一种将能量(包括燃料中的化学能和电能)转换为机械能的机器,通常通过旋转轴或推力产生动力。例子包括内燃机、燃气轮机和蒸汽轮机、火箭发动机、电动、液压和气动马达。
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)。
Meyer hardness (Unit Pa) 迈耶硬度(单位Pa) A material hardness similar to the Brinell hardness but based upon the projected area of the impression rather than the surface area.
与布氏硬度相似的材料硬度,但基于印模的投影面积而不是表面面积。
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。
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。
Balance piston 平衡活塞 (balance drum, dummy piston) A disc attached to the shaft of a turbine or compressor, to one side of which high or low pressure is applied to counteract the axial thrust produced by the pressure change across the machine. A form of thrust bearing.
(平衡鼓,假活塞)连接在涡轮机或压缩机轴上的圆盘,在其一侧施加高压或低压,以抵消机器压力变化产生的轴向推力。推力轴承的一种形式。
Eutectoid 共析 (1) An isothermal reversible reaction in which a solid solution is converted into two or more intimately mixed solids on cooling, the number of solids formed being the same as the number of components in the system. (2) An alloy having the composition indicated by the eutectoid point on an equilibrium diagram. (3) An alloy structure of intermixed solid constituents formed by a eutectoid reaction.
(1)一种等温可逆反应,其中固溶体在冷却时转化为两种或两种以上紧密混合的固体,形成的固体数量与系统中组分的数量相同。(2)具有平衡图上共析点所示成分的合金。(3)由共析反应形成的混合固体成分的合金结构。
Nautical mile (M) 海里(M) A special unit of distance employed for marine and aerial navigation. The conversion to SI is 1 M = 1 852 m.
用于海上和空中导航的特殊距离单位。SI的转换为1M=1852m。
Microindentation hardness test 显微压痕硬度测试 Hardness test using a calibrated machine to force a diamond indenter of specific geometry, under a test load of 1 to 1000 gramforce, into the surface of the test material and to measure the diagonal or diagonals of the indentation optically.
使用校准机器进行硬度试验,以在1至1000克力的试验载荷下,将特定几何形状的金刚石压头压入试验材料表面,并光学测量压痕的对角线。
Cooling coil 冷却盘管 A simple heat exchanger consisting of a coiled tube, typically of copper or stainless steel, through which is circulated a coolant such as a refrigerant, chilled water, or water mixed with ethylene glycol. Applications include air conditioning, process cooling, and refrigeration.
一种简单的热交换器,由通常由铜或不锈钢制成的盘管组成,冷却剂如制冷剂、冷冻水或与乙二醇混合的水通过盘管循环。应用包括空调、工艺冷却和制冷。
Uniform elongation 均匀伸长 The elongation at maximum load and immediately preceding the onset of necking in a tension test.
在拉伸试验中,在最大载荷下和颈缩开始之前的伸长率。
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。
Springback 回弹 The extent to which metal tends to return to its original shape or contour after undergoing a forming operation.
金属在经历成形操作后趋于恢复其原始形状或轮廓的程度。
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。
Combined stresses 复合应力 The stress state at a point in a component subjected to combination of axial, bending, torsional loadings etc., acting along all reference axes.
沿所有参考轴作用的受轴向、弯曲、扭转载荷等组合作用的部件中某点的应力状态。
Centrifugal 离心式 Acting or moving in a direction away from the axis of rotation of a rotating body.
沿远离旋转体的旋转轴的方向作用或移动。
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。
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。
Eyebolt (eyescrew) 吊环螺栓(眼螺丝) A bolt threaded at one end and bent to a loop at the other end. A bolt or screw with a closed loop in place of a head.
一端有螺纹,另一端弯曲成环的螺栓。带有闭合环代替头部的螺栓或螺钉。
Compound pendulum 复摆 A rigid body free to swing about an axis.
可绕轴自由摆动的刚体。
Observed value 观测值 The particular value of a characteristic determined as a result of a test or measurement.
作为测试或测量结果确定的特性的特定值。
Crank angle (Unit °) 曲柄角度(单位°) The angle between the crank of a slider-crank mechanism and a line from the crankshaft centreline to the piston axis.
曲柄滑块机构的曲柄与曲轴中心线到活塞轴线的直线之间的角度。
Conduit 导管 A hollow object, of metal, plastic, glass, ceramic, etc., which is relatively long compared with its lateral dimensions and through which there is fluid flow.
由金属、塑料、玻璃、陶瓷等制成的中空物体,与其横向尺寸相比相对较长,并且有流体流过。
Centre line 中心线 1. In an engineering drawing, a line of symmetry. 2. An imaginary line along a pipe, duct, or shaft that defines an axis of symmetry. 3. An imaginary straight line parallel to the intended direction of a surface located such that the areas above and below the line and the real wavy (rough) surface cancel out.
1.在工程图中,对称线。2.沿着管道、管道或竖井定义对称轴的假想线。3.一条平行于表面预期方向的假想直线,该直线上方和下方的区域与真实的波状(粗糙)表面相抵消。
Cooling curve 冷却曲线 A curve showing the relation between time and temperature during the cooling of a material.
显示材料冷却过程中时间和温度之间关系的曲线。
Vacuum servo 真空服务器 A vacuum-operated servomotor which is used in a motor vehicle to provide a brake effort greater than the capability of the driver.
一种真空操作的伺服电机,用于机动车中,以提供大于驾驶员能力的制动力。
Vacuum carburizing 真空渗碳 A high-temperature gas carburizing process using furnace pressures between 7 and 55 kPa during the carburizing portion of the cycle.
在循环的渗碳部分期间使用7至55kPa之间的炉压的高温气体渗碳工艺。
Washer 垫圈 An annular disc of metal, rubber, plastic, ceramic, etc., placed between two surfaces in contact either to spread the load (for example, between a surface and a tightened nut or a bolt head), to provide a seal, or to separate or align components.
由金属、橡胶、塑料、陶瓷等制成的环形圆盘,放置在两个接触面之间,以分散载荷(例如,在一个表面和拧紧的螺母或螺栓头之间),提供密封,或分离或对齐部件。
Materials science 材料科学 The study of the properties, behaviour, and application of solid substances such as metals, ceramics, glasses, polymers, composites, biomaterials, and semiconductors, at all scales from the atomic to the macroscopic. The topic has its origins in metallurgy.
研究金属、陶瓷、玻璃、聚合物、复合材料、生物材料和半导体等固体物质的特性、行为和应用,涵盖从原子到宏观的所有范围。起源于冶金学。
Volume (Unit m³) 体积(单位m³) The amount of space occupied by a specified mass of substance or by an object.
一定质量的物质或物体占据的空间量。
Remaining stress 残留应力 The stress remaining at a given time during a stress-relaxation test. See also stress relaxation.
在应力松弛试验期间在给定时间内剩余的应力。参见压力松弛。
Oil quenching 油淬 Hardening of carbon steel in an oil bath. Oils are categorized as conventional, fast, martempering, or hot quenching.
碳钢在油浴中的硬化。分为常规、快速、马氏体淬火或热淬火。
Critical load (Unit N) 临界负荷(单位N) 1. The applied load that causes propagation of an existing crack of known length, and hence fracture of a component or structure. 2. The applied load that results in buckling of a column of given end fixity.
1.导致已知长度的现有裂纹扩展并因此导致部件或结构断裂的施加荷载。2.导致具有给定端部固定性的柱屈曲的施加荷载。
Belt drive 带传动 Transmission of motion from one shaft to another by means of a continuous plain, or toothed, flexible band (belt) passing over pulleys. In contrast to chain drives, belt drives tend to be employed in low-torque applications. Reduction in transmissible power may occur due to stretch of a plain transmission belt which results in slack in the drive (belt creep) or slip of a belt on a driving or driven pulley (belt slip).
通过穿过滑轮的连续平带或带齿柔性带(带)将运动从一根轴传递到另一根轴。与链条传动相比,皮带传动往往用于低扭矩应用。由于普通传动带的拉伸可能会导致传动松弛(皮带蠕变)或主动或从动皮带轮上的皮带打滑(皮带打滑),从而导致传动功率降低。
Eutectic carbide 共晶碳化物 Carbide formed during freezing as one of the mutually insoluble phases participating in the eutectic reaction of ferrous alloys.
在冷冻过程中形成的碳化物,是参与铁合金共晶反应的互不溶相之一。
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。
Tightness 紧密度 A measure of the mass leak rate from a gasketed joint.
垫圈接头质量泄漏率的测量值。
Alloy steels 合金钢 Steels that contain alloying elements such as chromium, nickel, molybdenum, manganese, silicon, tungsten, and vanadium. These are added to improve properties such as the hardenability, toughness, strength, wear resistance, and corrosion resistance compared with those of plain-carbon steel. Low-alloy steels have a total alloy content (including carbon) of less than about 8%. They are hardenable and have strength up to 30% higher than plain-carbon steels. High-alloy steels contain considerably more alloy content and are developed for specific properties such as superior corrosion and chemical resistance.
含有铬、镍、钼、锰、硅、钨和钒等合金元素的钢。添加这些是为了提高与普通碳钢相比的淬透性、韧性、强度、耐磨性和耐腐蚀性等性能。低合金钢的总合金含量(包括碳)小于约8%。它们是可硬化的,强度比普通碳钢高出30%。高合金钢含有相当多的合金含量,并针对特定性能而开发,例如卓越的耐腐蚀性和耐化学性。
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。
Combustion deposit 燃烧沉积物 Ash, carbon, and other incombustible solids, often due to impurities in the fuel, that build up on any surfaces exposed to products of combustion. They can lead to corrosion, reduced heat transfer and so higher flue-gas temperatures and reduced efficiency.
灰、碳和其他不燃固体,通常是由于燃料中的杂质,在暴露于燃烧产物的任何表面上堆积。它们会导致腐蚀、传热降低,从而导致烟气温度升高和效率降低。
Transition temperature (Unit K) 转变温度(单位K) (1) An arbitrarily defined temperature that lies within the temperature range in which metal fracture characteristics (as usually determined by tests of notched specimens) change rapidly, such as from primarily fibrous (shear)to primarily crystalline (cleavage) fracture. (2) Sometimes used to denote an arbitrarily defined temperature within a range in which the ductility changes rapidly with temperature. (transition point) 1. The temperature at which the mechanism of fracture in metal alloys having a face-centred cubic crystal structure changes from ductile void growth to brittle cleavage. 2. The temperature at which a material changes from one crystal state to another.
(1) 任意定义的温度,位于金属断裂特性(通常通过缺口试样的试验确定)快速变化的温度范围内,如从主要纤维(剪切)断裂到主要结晶(解理)断裂。(2) 有时用于表示延性随温度快速变化的范围内的任意定义的温度。(转变点)1.具有面心立方晶体结构的金属合金的断裂机制从韧性孔洞生长转变为脆性解理的温度。2.材料从一种晶体状态转变为另一种晶体的温度。
Spring clip 弹簧夹 A clip made of a material such as spring steel which grips an inserted part.
由弹簧钢等材料制成的夹子,用于夹住插入的零件。
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。
Secant modulus 割线模量 The slope of the secant drawn from the origin to any specified point on a stress-strain curve. Compare with chord modulus.
从原点到应力应变曲线上任何指定点的割线斜率。与弦模量进行比较。
Cylinder head 气缸盖 The machined casting, typically of aluminium alloy or cast iron, that fits above the cylinder block of a piston engine and closes off the cylinders. It normally includes part of the combustion chambers and holes for the valves and spark plugs.
活塞式发动机缸体上方的机械铸件,通常由铝合金或铸铁制成,用于封闭气缸。它通常包括燃烧室的一部分以及阀门和火花塞的孔。
Static equilibrium 静态平衡 A solid body, structure, or physical system (or any subdivided part) will be in static equilibrium, either at rest or moving with constant velocity, if the resultants of all external forces and moments acting on it are zero.
如果作用在固体上的所有外力和力矩的合力为零,则固体、结构或物理系统(或任何细分部分)无论是静止还是以恒定速度移动,都是处于静态平衡。
Hydraulics 液压系统 The study of water flow in open channels (including canals, rivers, etc.), water-supply, drainage, and irrigation systems.
研究明渠(包括运河、河流等)、供水、排水和灌溉系统中的水流。
Compressor blades 压缩机叶片 The aerofoil-shaped vanes that form the rotor(s) and stator(s) of an axial-flow compressor. The aerodynamic design is more critical than is the case for turbine blades because there is an increase in pressure across each row of blades. The arrows in the diagram indicate the flow direction relative to the blades.
形成轴流式压缩机的转子和定子的翼型叶片。空气动力学设计比涡轮叶片的情况更为关键,因为每排叶片的压力都会增加。图中的箭头表示相对于叶片的流动方向。
Flat head 平头 Flat top surface and a conical bearing surface.
平顶表面和锥形轴承表面。
Intergranular fracture 沿晶破裂 Brittle fracture of a metal in which the fracture is between the grains, or crystals, that form the metal. Also called intercrystalline fracture.
金属的脆性断裂,断裂位于形成金属的晶粒或晶体之间。又称晶间破裂。
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。
Design load (Unit N) 设计荷载(单位N) The greatest load that a component or structure is expected to experience under normal operating conditions.
部件或结构在正常运行条件下预期承受的最大负载。
Gear ratio 传动比 For two gears in contact, the ratio of the number of teeth on the driving gear to that on the driven gear.
对于接触的两个齿轮,主动齿轮上的齿数与从动齿轮上的齿数之比。
Knot (kn) 节(kn) A non-SI unit defined as one nautical mile per hour. The conversion to SI is 1 kn = 5.144 444 444×10−1 m/s.
非国际单位制单位,定义为每小时一海里。转换为SI为1kN=5.144444×10−1米/秒。
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