| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Biodiesel | 生物柴油 |
A substitute for diesel fuel derived from the oily seeds of sunflowers, oilseed rape, soya beans, etc. 从向日葵、油菜、大豆等的油性种子中提取的柴油的替代品。 |
| Nominal size | 公称尺寸 |
The intended size of a component. The actual size will depend on manufacturing tolerances. 组件的预期尺寸。实际尺寸取决于制造公差。 |
| Free joint | 万向节 |
The joint on a robot arm and wrist that causes the greatest end-effector movement when a specified force is applied to the end effector, i.e. that has the lowest stiffness with regard to the force. 机器人手臂和手腕上的关节，当指定的力施加到末端执行器时，会导致末端执行器的最大运动，即相对于力具有最低刚度。 |
| 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。 |
| Hysteresis | 滞后 |
The phenomenon of permanently absorbed or lost energy that occurs during any cycle of loading or unloading when a material is subjected to repeated loading. 当材料经受重复加载时，在任何加载或卸载循环期间发生的永久吸收或损失能量的现象。 |
| 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。 |
| Vapour-pressure thermometer | 蒸汽压力温度计 |
(vapour-filled thermometer) A type of fluidexpansion thermometer in which the working fluid is a volatile liquid. （蒸汽填充温度计）一种流体膨胀温度计，其中工作流体为挥发性液体。 |
| Rotor | 转子 |
A part of a machine that rotates on a shaft (rotor shaft) about its own axis, such as the blade-carrying discs of a turbine, the blades of a helicopter, or the rotating parts of a Roots blower. 绕轴（转子轴）绕其自身轴线旋转的机器部件，如涡轮叶片、直升机叶片或罗茨鼓风机的旋转部件。 |
| Vane engine (vane motor) | 叶片发动机（叶片马达） |
A rotary engine in which high-pressure hydraulic fluid in the spaces between spring-loaded sliding vanes held in an offset rotor acts on the vanes, causing the rotor to revolve within a cylinder. The design is much like a sliding-vane compressor, as is that of a vane pump, used to pump liquids. 一种旋转式发动机，其中偏置转子中装有弹簧的滑动叶片之间的高压液压流体作用在叶片上，使转子在气缸内旋转。这种设计很像滑动叶片压缩机，就像用于泵送液体的叶片泵一样。 |
| 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。 |
| Fatigue test | 疲劳测试 |
A method for determining the range of alternating (fluctuating)stresses a material can withstand without failing. 一种确定材料可以承受而不会失效的交变（波动）应力范围的方法。 |
| Chilled castings | 冷铸件 |
Iron castings cooled at a rate that results in white iron (slow enough to avoid the formation of martensite, yet fast enough to prevent any silicon present from causing decomposition of cementite into iron and graphite). 铸铁件以产生白口铁的速度冷却（足够慢以避免形成马氏体，但足够快以防止任何存在的硅导致渗碳体分解成铁和石墨）。 |
| 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。 |
| 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。 |
| Graphitic carbon | 石墨碳 |
Free carbon in steel or cast iron. 钢或铸铁中的游离碳。 |
| Absolute manometer | 绝对压力计 |
A manometer that measures absolute pressure, i.e. pressure measured relative to a perfect vacuum. Absolute pressure cannot be negative. 测量绝对压力的压力计，即相对于完美真空测量的压力。绝对压力不能为负。 |
| Boiler and Pressure Vessel Code | 锅炉和压力容器规范 |
A large and complex document, maintained and published by the American Society of Mechanical Engineers. The code 一份庞大而复杂的文件，由美国机械工程师协会出版和维护。 |
| 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。 |
| 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。 |
| Multiple threaded screw | 多螺纹螺钉 |
A screw with two or more threads cut around the periphery of the workpiece to provide an increased lead with a specified pitch. 一种螺钉，具有围绕工件周边切割的两个或多个螺纹，以提供具有指定螺距的增加的导程。 |
| Bond strength (Unit Pa) | 结合强度（单位Pa） |
The tensile, compressive or shear stress at which joints fail, e.g. by fracture or excessive deformation. 接头失效的拉伸、压缩或剪切应力，例如断裂或过度变形。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Crankshaft | 曲轴 |
The main shaft, of which the cranks are a part, of a reciprocating single-or multi-cylinder machine. Crankshafts may be built up in sections or forged as a single component. In an engine, the reciprocating motion of the pistons transmits power to the crankshaft and causes it to rotate, whereas in a pump the crankshaft is driven and its rotation causes the pistons to reciprocate. 曲柄是往复式单缸或多缸机器主轴的一部分。曲轴可以分段组装或作为单个部件锻造。在发动机中，活塞的往复运动将动力传递给曲轴并使其旋转，而在泵中，曲轴被驱动，其旋转使活塞往复运动。 |
| Effective yield strength | 有效屈服强度 |
An assumed value of uniaxial yield strength that represents the influence of plastic yielding on fracture test parameters. 单轴屈服强度的假设值，代表塑性屈服对断裂试验参数的影响。 |
| 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。 |
| 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。 |
| Hot pressing | 热压 |
1. Sintering of metal or ceramic powder at high temperature. 2. Formation of components from fibre-reinforced composite material in which bonding is ensured through application of pressure and temperature, often against a mould to give the required shape. 1、金属或陶瓷粉末的高温烧结。2. 由纤维增强复合材料形成部件，其中通过施加压力和温度来确保粘合，通常靠在模具上以形成所需的形状。 |
| Kinetic energy | 动能 |
Energy that an object possesses because it is in motion. It is the energy given to an object to set it in motion. On impact, it is converted into other forms of energy such as strain, heat, sound and light. 物体因运动而拥有的能量。它是赋予物体使其运动的能量。撞击时，它被转换成其他形式的能量，如应变、热、声和光。 |
| 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。 |
| 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。 |
| 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。 |
| 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）。 |
| Swept volume (Unit m³) | 扫描体（单位m³) |
In the cylinder of a piston engine or other device, the volume between top and bottom dead centre positions of a piston; equal to πR2S where R is the piston radius and S is the stroke. 在活塞发动机或其他装置的气缸中，活塞上止点和下止点位置之间的体积；等于πR2S，其中R是活塞半径，S是冲程。 |
| 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。 |
| Coherent precipitate | 相干沉淀 |
A crystalline precipitate that forms from solid solution with an orientation that maintains continuity between the crystal lattice of the precipitate and the lattice of the matrix, usually accompanied by some strain in both lattices. Because the lattices fit at the interface between precipitate and matrix, there is no discernible phase boundary. 由固溶体形成的结晶沉淀物，其取向保持沉淀物晶格和基体晶格之间的连续性，通常伴随着两个晶格中的一些应变。由于晶格适合于沉淀和基体之间的界面，因此不存在可识别的相边界。 |
| 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。 |
| Eutectic | 共晶 |
(1) An isothermal reversible reaction in which a liquid 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 eutectic point on an equilibrium diagram. (3) An alloy structure of intermixed solid constituents formed by a eutectic reaction. （1）一种等温可逆反应，其中液体溶液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）一种合金，其成分由平衡图上的共晶点表示。（3）由共晶反应形成的混合固体成分的合金结构。 |
| Finished hexagon bolts | 精制六角螺栓 |
A washer faced or chamfered bearing surface with a close body tolerance. 头下有垫圈面或倒角，尺寸公差小 |
| Fatigue limit for p % survival | p%存活率的疲劳极限 |
The limiting value of fatigue strength for p%survival as the number of stress cycles becomes very large; pmay be any number, such as 95, 90, etc. 随着应力循环次数的增加，p%存活率的疲劳强度极限值变得非常大；p可以是任何数字，例如95、90等。 |
| Transfer machines | 转印机 |
These specialized machine tools are used to perform various machining operations on parts or parts in fixtures as the parts are moved along on an automatic conveyor which is part of the machine tool set-up. In a set-up, the parts can move in a straight line from their entry point to their exit point, or the setup may be constructed in a U-shape so that the parts are expelled near where they start. 当零件在自动输送机上移动时，这些专用机床用于对零件或夹具中的零件执行各种加工操作，自动输送机是机床设置的一部分。在设置中，零件可以从其入口点直线移动到其出口点，或者设置可以构造为U形，以便零件在其起点附近排出。 |
| Gasket m-factor | 垫片m系数 |
For a gasketed joint of area A in which the clamping force is F, the factor m is defined by F ≥ mpA where p is the pressure that would separate the two halves of the joint and m > 1. 对于面积为A且夹紧力为F的垫片接头，系数m由F≥mpA定义，其中p是分离接头两半的压力，m>1。 |
| Concentrated load | 集中负荷 |
A load on a component which is distributed over a very small area, idealized as the line load of a wedge or knife edge, and the point load of a cone. 分布在非常小的区域上的部件上的载荷，理想化为楔形或刀刃的线载荷和锥体的点载荷。 |
| 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。 |
| 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。 |
| Bypass valve | 旁通阀 |
A valve that directs flow through a bypass. 引导流过旁路的阀门。 |
| Threshold stress for stress-corrosion cracking (σth) | 应力腐蚀开裂阈值应力（σth） |
An experimentally determined critical gross-section stress below which stress-corrosion cracking will not occur under specified test conditions. 实验确定的临界总截面应力，低于该应力，在规定的试验条件下不会发生应力腐蚀开裂。 |
| Mohs scale | 莫氏硬度 |
A scale of scratch hardness originally developed for minerals. 最初为矿物开发的划痕硬度标尺。 |
| Flange rotation | 法兰转角 |
Angular distortion of a flange under the influence of bolt and reaction forces. Measured with respect to the center of the cross section of the flange. 法兰在螺栓和反作用力影响下的角度变形。相对于法兰横截面的中心测量。 |
| 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。 |
| System engineering | 系统工程 |
A methodology which integrates all disciplines and specialty groups into a team effort, forming a structured development process that proceeds from concept to production to operation. 一种将所有学科和专业组整合到团队工作中的方法，形成从概念到生产再到运营的结构化开发过程。 |
| 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。 |
| Stress-concentration factor (Kt) | 应力集中系数（Kt） |
A multiplying factor for applied stress that allows for the presence of a structural discontinuity such as a notch or hole; Kt equals the ratio of the greatest stress in the region of the discontinuity to the nominal stress for the entire section. Also known as theoretical stress-concentration factor. 施加应力的倍增系数，允许存在结构不连续性，如缺口或孔；Kt等于不连续区域的最大应力与整个截面的标称应力之比。也称为理论应力集中系数。 |
| Gibbs–Dalton law | 吉布斯-道尔顿定律 |
An extension of Dalton’s law of additive pressures to include the statement that the internal energy, enthalpy, and entropy of a mixture of gases are equal to the sum of the internal energies, enthalpies, and entropies the individual constituents would have if each existed alone at the same temperature and volume. Gibbs rule is that part of the law pertaining to entropy. 道尔顿附加压力定律的扩展，包括以下陈述：气体混合物的内能、焓和熵等于各个成分单独存在时的内能、焓和熵之和。相同的温度和体积。吉布斯定律是与熵有关的定律的一部分。 |
| Press quenching | 压淬 |
A quench in which hot dies are pressed and aligned with a part before the quenching process begins. Then the part is placed in contact with a quenching medium in a controlled manner. This process avoids part distortion. 一种淬火方法，在淬火过程开始之前，热模具被压制并与零件对齐。然后将零件以受控方式放置在与淬火介质接触的位置。该过程避免了零件变形。 |
| 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。 |
| Absolute specific gravity | 绝对比重 |
The ratio of the weight of any volume of a substance to the weight of an equal volume of a reference substance at the same temperature, often water at 4°C, both measured in a vacuum to avoid any effect of buoyancy. 在相同温度下，任何体积的物质的重量与等体积的参考物质的重量之比，通常是4°C的水，两者都是在真空中测量的，以避免任何浮力的影响。 |
| Pressure surface | 压力面 |
The high-pressure surface of an aerofoil, turbine, or compressor blade. In normal aircraft applications, this is the lower surface of a wing. For applications, such as to high-performance motor vehicles, where the aerofoil is inverted to generate downforce, it is the upper surface. 机翼、涡轮或压缩机叶片的高压表面。在正常的飞机应用中，这是机翼的下表面。对于高性能机动车辆等应用，机翼翻转以产生下压力，它是上表面。 |
| Composite property | 复合属性 |
In thermodynamics, a property defined in terms of the properties of a closed system and its surroundings, such as the non-flow exergy function. 在热力学中，根据封闭系统及其周围环境的性质定义的性质，例如非流动火用函数。 |
| 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。 |
| 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。 |
| Coefficient of rolling friction | 滚动摩擦系数 |
The ratio of force parallel to a surface, on which an object rolls, to the normal force. Unlike sliding friction, rolling friction depends on the size of the contact patch and the radius of the rolling element, and the behaviour depends on whether the contact is elastic, viscoelastic, or plastic and on hysteresis losses. 平行于物体滚动表面的力与法向力之比。与滑动摩擦不同，滚动摩擦取决于接触片的大小和滚动元件的半径，其行为取决于接触是弹性的、粘弹性的还是塑性的以及滞后损失。 |
| 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。 |
| Degradation failure | 退化失效 |
Failure of a system, component, or structure owing to material degradation. 由于材料退化导致的系统、组件或结构失效。 |
| Notch brittleness | 缺口脆性 |
Susceptibility of a material to brittle fractureat points of stress concentration. For example, in a notch tensile test, the material is said to be notch brittle if the notch strengthis less than the tensile strength of an unnotched specimen. Otherwise, it is said to be notch ductile. 材料在应力集中点易发生脆性断裂。例如，在缺口拉伸试验中，如果缺口强度小于无缺口试样的抗拉强度，则称材料为缺口脆性材料。否则，称其为缺口韧性。 |
| Lead screw | 丝杠 |
The master screw running along the length of the bed of a lathe from which all screws threads on that machine are cut. Master screw used for cutting a screw thread in a lathe. 沿车床床身长度方向运行的主螺钉，该机床上的所有螺钉和螺纹都从主螺钉上切割下来。用于在车床上切削螺纹的主螺钉。 |
| Refractory materials | 耐火材料 |
Metals or ceramics that do not melt when exposed to temperature above about 1 500°C or deteriorate rapidly in a continuous temperature above about 550°C. 当暴露于高于约1500°C的温度时不熔化或在高于约550°C的连续温度下快速劣化的金属或陶瓷。 |
| Regenerative pump | 涡流泵 |
(regenerative turbine pump, peripheral pump) A pump with a double-sided impeller having a large number of radial blades. The pressure of the pumped liquid increases progressively over several revolutions of the impeller. It is particularly suited to producing large heads at small flow rates without cavitation. （再生涡轮泵，外围泵）具有具有大量径向叶片的双面叶轮的泵。泵送液体的压力在叶轮的几圈内逐渐增加。它特别适合于在小流速下产生大水头且不产生气穴。 |
| 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。 |
| Seal | 密封件 |
A component which controls or prevents leakage of fluids into or out of parts of a machine. 控制或防止流体流入或流出机器部件的部件。 |
| Minute (min) | 分钟（min） |
A non-SI unit of time. The conversion to SI is 1 min = 60 s. 非SI时间单位。转换为1分钟=60秒。 |
| Stress factor | 应力因子 |
A calibration constant used in ultrasonic measurement of bolt stress or strain. It is the ratio between the change in ultrasonic transit time caused by the change in length of the fastener, under load, to the total change in transit time. 用于螺栓应力或应变超声波测量的校准常数。它是由紧固件长度变化引起的超声波传输时间变化与总传输时间变化之间的比率。 |
| Graham’s laws | 格雷厄姆定律 |
The laws stating that the rates of diffusion and effusion of a gas are inversely proportional to the square root of its density. 规定气体的扩散和渗出速率与其密度的平方根成反比的定律。 |
| Mechanical alloying | 机械合金化 |
Production of alloys from powders by consolidation, e.g. hotpressing or extrusion, followed by hot and/or cold working and final annealing. Materials such as dispersion-strengthened alloys, high-temperature aluminium alloys, and amorphous alloys can be made in this way. 通过固结（例如热压或挤压）从粉末生产合金，然后进行热和/或冷加工和最终退火。用这种方法可以制造弥散强化合金、高温铝合金和非晶合金等材料。 |
| Zero-gravity | 零重力 |
The situation in which there is no force of gravity (i.e. weightlessness). 没有重力的情况（即失重）。 |
| Fog quenching | 雾淬 |
Quenching in a fine vapor or mist. 在细蒸汽或薄雾中淬火。 |
| Cleavage fracture | 解理断裂 |
A fracture, usually of a polycrystalline metal, in which most of the grains have failed by cleavage, resulting in bright reflecting facets. It is one type of crystalline fracture and is associated with low energy brittle fracture. Contrast with shear fracture. A fracture created by splitting (cleavage), as between layers in materials like slate or mica. In brittle metals, and brittle microconstituents in alloys, cleavage occurs along particular crystal planes. 一种通过分裂（劈裂）产生的裂缝断裂，通常是多晶金属的断裂，其中大部分晶粒因解理而失效，产生明亮的反射面。它是一种结晶性断裂，与低能脆性断裂有关。与剪切断裂相对。如板岩或云母等材料的层之间。在脆性金属和合金中的脆性微量成分中，沿特定晶面发生解理。 |
| 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。 |
| Ablation cooling | 烧蚀冷却 |
The cooling of a surface exposed to very high external gas temperature which causes the surface material to sublime, melt or decompose. The chemical process absorbs heat while the mass flow of material away from the surface blocks the heat flux from the hot gas. 冷却暴露于非常高的外部气体温度的表面，导致表面材料升华、熔化或分解。化学过程吸收热量，而远离表面的物质的质量流阻挡了来自热气体的热通量。 |
| Liquation temperature | 液化温度 |
The lowest temperature at which partial melting can occur in an alloy that exhibits the greatest possible degree of segregation. 偏析程度最高的合金发生部分熔融的最低温度。 |
| Terminal temperature difference (Unit K) | 终端温差（单位K） |
The temperature difference between the two fluid streams at either inlet or outlet of a heat exchanger. 热交换器入口或出口处两种流体流之间的温差。 |
| 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。 |
| Face | 表平面 |
To machine a flat surface perpendicular to the axis at rotation on a lathe. 在车床上加工一个垂直于旋转轴的平面。 |
| 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。 |
| Constant-mesh gearbox | 恒啮合齿轮箱 |
A gearbox in which the pairs of gears giving different speed ratios are constantly in mesh, different ratios being obtained by connecting or disconnecting the relevant gear to the driving shaft. 一种齿轮箱，其中提供不同速比的齿轮对始终啮合，通过将相关齿轮连接或断开驱动轴获得不同的速比。 |
| Volumetric efficiency | 容积效率 |
For a piston engine, the ratio of the volume of the induced charge per induction stroke, determined at a reference pressure and temperature, to the swept volume. 对于活塞式发动机，在参考压力和温度下确定的每个进气冲程的进气体积与扫掠体积之比。 |
| Cavity radiator | 空腔辐射器 |
A heated chamber having a small hole through which radiation, approximating blackbody radiation, passes out. 具有小孔的加热室，近似于黑体辐射的辐射通过该小孔传递出去。 |
| Shank | 螺杆 |
Portion of a bolt which lies under the head. 1. The stem of a tool, such as a broach, drill bit, reamer, or tap, which fits into a holder such as a chuck. 2. The stem of a rivet or the unthreaded part of a screw or bolt. 3. The shaft of a tool connecting the tip and the handle. 螺栓头部下方的部分。1.一种工具的柄部，如拉刀、钻头、铰刀或丝锥，可装入夹具（如卡盘）中。铆钉的杆或螺钉或螺栓的无螺纹部分。3.连接尖端和手柄的工具的轴。 |
| Transfer ratio | 传输比 |
(transfer constant) A complex variable representing the ratio between the output of a transducer and the input causing that output. （传递常数）一个复变量，表示传感器输出与产生该输出的输入之间的比率。 |
| Diaphragm compressor | 隔膜式压缩机 |
A machine in which compression is achieved by the reciprocating motion of a flexible membrane of metal, plastic, or elastomeric material. This arrangement is ideally suited to pumping high-purity, toxic, or explosive gases. A similar machine incorporating check valves is a self-priming positive-displacement pump (diaphragm pump, membrane pump). 通过金属、塑料或弹性材料的柔性薄膜的往复运动实现压缩的机器。这种布置非常适合泵送高纯度、有毒或爆炸性气体。装有止回阀的类似机器是自吸容积泵（隔膜泵、隔膜泵）。 |
| 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。 |
| Fit | 装配 |
The general term used to signify the range of tightness which may result from the application of a specific combination of allowances and tolerances in the design of mating parts. 通用术语，用于表示配合零件设计中公差和公差的特定组合可能导致的紧密性范围。 |
| 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。 |
| Butt joint | 对接接头 |
The end-to-end joining of two plates either by welding or by overlapping plates that are bolted or riveted. 通过焊接或通过螺栓或铆接的重叠板将两块板端对端连接。 |
| Complete decarburization | 完全脱碳 |
Decarburization with sufficient carbon loss to show only clearly defined ferrite grains under metallographic examination. 脱碳，具有足够的碳损失，以在金相检查下仅显示清晰定义的铁素体晶粒。 |
| Anelastic | 无弹性 |
Literally ‘not elastic’, but in practice used for materials that display timedependent recovery on unloading. 字面意思是“没有弹性”，但实际上用于在卸载时显示随时间恢复的材料。 |
| 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。 |
| Decarburization | 脱碳 |
Loss of carbon from the surface layer of a carbon-containing alloy due to reaction with one or more chemical substances in a medium that contacts the surface. 由于与接触表面的介质中的一种或多种化学物质发生反应，含碳合金表面层的碳损失。 |
| Cycle annealing | 循环退火 |
An annealing process employing a predetermined and closely controlled time-temperature cycle to produce specific properties or microstructures. 采用预定且严格控制的时间-温度循环来产生特定性能或微观结构的退火工艺。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Fatigue strength | 疲劳强度 |
The stress to which a metal can be subjected for a specified number of cyclic changes of stress. The maximum stress that can be sustained for a specified number of cycles without failure. The value of the maximum stress and the stress ratio also should be stated. 金属在指定数量的应力循环变化下可以承受的应力。可以在指定的循环次数内持续而不失效的最大应力。还应说明最大应力值和应力比。 |
| 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。 |
| Strain rate | 应变率 |
The time rate of straining for the usual tensile test. Strain as measured directly on the specimen gage length is used for determining strain rate. Because strain is dimensionless, the units of strain rate are reciprocal time. 通常拉伸试验的应变时间速率。直接在试样标距上测量的应变用于确定应变率。因为应变是无因次的，所以应变率的单位是倒数时间。 |
| Quench aging | 淬火时效 |
Aging induced by rapid cooling after solution heat treatment. 固溶热处理后快速冷却引起的时效。 |
| Standard gauge | 标准量规 |
A highly-accurate reference gauge against which to check working gauges. 一种高精度的基准量规，用于检查工作量规。 |
| Nipple | 喷嘴 |
A device containing a non-return valve screwed into a lubrication point through which grease may be introduced, for example into a bearing. 一种包含止回阀的装置，该止回阀拧入润滑点，通过该润滑点可以将润滑脂引入，例如轴承中。 |
| Bioengineering | 生物工程 |
(biological engineering) The application of engineering principles to biology, medicine, agriculture, etc. （生物工程）工程原理在生物学、医学、农业等方面的应用。 |
| Unison ring | 协调环 |
In a turbomachine with adjustable guide or stator vanes, the ring to which a set of vanes is linked such that when the ring is rotated, all vane angles are adjusted. 在具有可调导向叶片或定子叶片的涡轮机中，一组叶片连接到的环，当环旋转时，所有叶片角度都可调整。 |
| Plane stress | 平面应力 |
The stress condition in linear-elastic fracture mechanics in which the stress in the thickness direction is zero; most nearly achieved in loading very thin sheet along a direction parallel to the surface of the sheet. Under plane-stress conditions, the plane of fracture instability is inclined 45° to the axis of the principal tensile stress. 线弹性断裂力学中厚度方向上的应力为零的应力条件；在沿着平行于薄片表面的方向加载非常薄的薄片时最接近。在平面应力条件下，断裂失稳平面与主拉应力轴倾斜45°。 |
| Microscopic stresses | 微观应力 |
Residual stresses that vary from tension to compression in a distance (presumably approximating the grain size) that is small compared with the gage length in ordinary strain measurements. They are not detectable by dissection methods, but can sometimes be measured from line shift or line broadening in an x-ray diffraction pattern. 与普通应变测量中的标距相比，从拉伸到压缩的距离（大概接近晶粒尺寸）较小的残余应力。它们无法通过解剖方法检测到，但有时可以通过x射线衍射图案中的线位移或线加宽来测量。 |
| 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。 |
| Dislocation density | 位错密度 |
The total length of dislocation lines per unit volume, or the number of dislocation lines that cut through a unit cross-sectional area. 每单位体积的位错线的总长度，或穿过单位横截面积的位错线的数量。 |
| Combustion | 燃烧氧化 |
An exothermic chemical reaction in which a fuel and an oxidant, typically air, react together to release a significant quantity of thermal energy in the presence of a flame. In the case of fluid fuels, ignition may be from an electric spark or compression of the 一种放热化学反应，其中燃料和氧化剂（通常是空气）一起反应，在火焰存在的情况下释放大量热能。 |
| Gear motor | 齿轮马达 |
Essentially a gear pump run in reverse, in which high-pressure fluid supplied to one side of the casing causes the gears to rotate. 本质上是一个齿轮泵反向运行，其中供应到外壳一侧的高压流体导致齿轮旋转。 |
| Temper color | 回火颜色 |
A thin, tightly adhering oxide skin that forms when steel is tempered at a low temperature, or for a short time, in air or a mildly oxidizing atmosphere. The color, which ranges from straw to blue depending on the thickness of the oxide skin, varies with both tempering time and temperature. 一种薄的、紧密粘附的氧化皮，当钢在低温或短时间内在空气或轻度氧化气氛中回火时形成。颜色范围从稻草色到蓝色，取决于氧化皮的厚度，随回火时间和温度而变化。 |
| 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。 |
| Thermal efficiency | 热效率 |
The ratio, for a heat engine or thermodynamic cycle, of the net work output to the net heat input into the system. 对于热机或热力循环，净功输出与系统净热输入的比率。 |
| Biaxial stress | 双轴应力 |
Generalized loading of a body in a single plane with no loading normal to it. 物体在一个平面内的广义载荷，没有垂直于它的载荷。 |
| Actual value | 实际价值 |
The output of a plant that is being controlled, i.e. the controlled variable. Not directly accessible by the control system, as it can only be measured by a sensor which may distort the measurement. 受控设备的输出，即受控变量。控制系统不能直接访问，因为它只能由可能会扭曲测量结果的传感器测量。 |
| R-curve/Resistance curve | 阻力曲线 |
In linear-elastic fracture mechanics, a plot of crack-extension resistance as a function of stable crack extension, which is either the difference between the physical crack size, or the effective crack size, and the original crack size. R-curves normally depend on specimen thickness and, for some materials, on temperature and strain rate. An increase in fracture toughness with crack propagation shown by rising plots of toughness vs growing crack length. 在线弹性断裂力学中，作为稳定裂纹扩展函数的裂纹扩展阻力图，即物理裂纹尺寸或有效裂纹尺寸与原始裂纹尺寸之间的差值。R曲线通常取决于试样厚度，对于某些材料，还取决于温度和应变率。是随着裂纹扩展，断裂韧性增加，表现为韧性与扩展裂纹长度的上升曲线。 |
| 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。 |
| 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。 |
| Square | 正方 |
1. A regular quadrilateral, i.e. a polygon with four equal sides and four right angles. 2. An instrument to check angles of internal and external surfaces and flatness. 1.正四边形，即具有四条等边和四个直角的多边形。2.一种检查内外表面角度和平面度的仪器。 |
| 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。 |
| 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。 |
| Vector | 矢量 |
Any physical quantity, such as velocity, acceleration, force, or momentum, that is specified in terms of both its magnitude and its direction. The convention of printing vector quantities in boldface was introduced by the physicist Josiah Willard Gibbs. 任何物理量，如速度、加速度、力或动量，以其大小和方向来表示。用黑体印刷矢量量的惯例是由物理学家约西亚·威拉德·吉布斯提出的。 |
| 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。 |
| Car furnace | 车炉 |
A batch-type furnace using a car on rails to enter and leave the furnace area. Car furnaces are used for lower stress relieving ranges. 一种间歇式炉，使用轨道上的小车进出炉区。汽车炉用于较低的应力消除范围。 |
| Proof load | 验证载荷（单位 N） |
The maximum, safe, static, tensile load which can be placed on a fastener without yielding it. Sometimes given as a force (in lb or N) sometimes as a stress (in psi or MPa). The test load in quality control to which different components made of different materials must be subjected without failing in order to perform properly. 可施加在紧固件上而不使其屈服的最大安全静态拉伸载荷。有时以力（lb或N）表示，有时以应力（psi或MPa）表示。质量控制中的测试负荷，由不同材料制成的不同部件必须经受该负荷，才能正常运行。 |
| Specific weight (γ) (Unit N/m³) | 比重（γ）（单位：N/m³） |
The weight per unit volume of a substance: if W is the weight of a volume of the substance, ρ is its density, and g is the acceleration due to gravity, γ = W/ = ρg. 物质单位体积的重量：W是物质体积的重量，ρ是其密度，g是重力引起的加速度，γ=W/=ρg。 |
| Absolute viscosity | 绝对粘度 |
A measure of the internal shear properties of fluids, expressed as the tangential force per unit area at either of two horizontal planes separated by one unit thickness of a given fluid, one of the planes being fixed and the other moving with unit velocity. 流体内部剪切特性的量度，表示为两个水平面中的任何一个上的单位面积切向力，两个水平面被给定流体的一个单位厚度隔开，其中一个平面固定，另一个以单位速度移动。 |
| 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。 |
| Latent heat | 潜热 |
Thermal energy absorbed or released when a substance undergoes a phase change. 物质发生相变时吸收或释放的热能。 |
| Extra hard | 额外硬化 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about one-third of the way from full hard to extra spring temper. 有色合金和一些铁合金的回火，其特征是抗拉强度和硬度大约是从完全硬回火到额外弹簧回火的三分之一。 |
| Stress–strain curve | 应力-应变曲线 |
(stress–strain diagram) A plot of stress vs strain for a solid material obtained from a test in which a specimen is loaded in tension, compression, shear, or combinations thereof. Diagrams of true stress vs true strain deviate from those of nominal stress vs nominal strain only at large strains where appreciable changes in cross section of testpieces occur. （应力-应变图）从试验中获得的固体材料的应力与应变图，其中试样在拉伸、压缩、剪切或其组合中加载。只有在试件横截面发生明显变化的大应变下，真实应力与真实应变图与标称应力与标称应变图不同。 |
| Hot-wire analyzer | 热电阻丝型分析仪 |
An electrical atmosphere analysis device that is based on the fact that the electrical resistivity of steel is a linear function of carbon content over a range from 0.05% C to saturation. The device measures the carbon potential of furnace atmospheres (typically). This term is not to be confused with the hot-wire test which measures heat extraction rates. 一种基于以下事实的电气氛分析设备：钢的电阻率是从0.05%C到饱和范围内的碳含量的线性函数。该设备测量炉内气氛的碳势（通常）。不要将此术语与测量热提取率的热线测试相混淆。 |
| Quench cracking | 淬火开裂 |
Fracture of a metal during quenching from elevated temperature. Most frequently observed in hardened carbon steel, alloy steel, or tool steel parts of high hardness and low toughness. Cracks often emanate from fillets, holes, corners, or other stress raisers and result from high stresses due to the volume changes accompanying transformation to martensite. 高温淬火时金属断裂。在高硬度和低韧性的硬化碳钢、合金钢或工具钢零件中最常见。裂纹通常来自圆角、孔、角部或其他应力集中区，并由伴随马氏体转变的体积变化引起的高应力引起。 |
| 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。 |
| 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。 |
| Slant fracture | 倾斜裂缝 |
A type of fracture appearance, typical of plane-stress fractures, in which the plane of metal separation is inclined at an angle (usually about 45°) to the axis of the applied stress. 一种断裂现象，典型的平面应力断裂，其中金属分离面与施加应力的轴成一定角度（通常约45°）倾斜。 |
| Cone clutch | 锥形离合器 |
A friction clutch in which an internal cone moves axially in or out of engagement with an external cone. One or both surfaces is lined with high-friction material. 一种摩擦离合器，其中内锥与外锥轴向啮合或脱离啮合。一个或两个表面衬有高摩擦材料。 |
| 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。 |
| Compression spring | 压缩弹簧 |
A spring that resists compression forces, usually in the form of a helix with separated coils (giving a linear axial stiffness) or a cone with separated coils (giving a non-linear axial stiffness). 一种抵抗压缩力的弹簧，通常采用带有分离线圈的螺旋形式（提供线性轴向刚度）或带有分离线圈的锥形（提供非线性轴向刚度）。 |
| Coining | 压印 |
A forging operation, employing a closely-fitting punch and die from which no metal is allowed to escape, in which the surface pattern on the punch and die is imprinted on the blank. 一种锻造操作，采用紧密配合的凸模和模具，不允许金属逸出，其中凸模和模具上的表面图案印在坯料上。 |
| 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。 |
| Pascal’s law | 帕斯卡定律 |
When there is a change in pressure at any point in a confined fluid at rest, there is an equal change at every other point in the fluid volume. 当处于静止状态的受限流体中任何一点的压力发生变化时，流体体积中的每一点的变化都相等。 |
| Supercooling | 过冷 |
Cooling below the temperature at which an equilibrium phase transformation can take place, without actually obtaining the transformation. 在没有实际获得相变的情况下，冷却到可以发生平衡相变的温度以下。 |
| Vernier | 游标 |
A short auxiliary scale that slides along the main instrument scale to permit more accurate fractional reading of the least main division of the main scale. 一种短辅助刻度，沿主仪表刻度滑动，以便更准确地读取主刻度的最小主刻度。 |
| Acceleration due to gravity | 重力加速度 |
(acceleration of free fall, gravitational acceleration, g) (Unit m/s²) The acceleration of a freely-falling body in a vacuum, with a mean value at sea level of approximately 9.81 m/s². （自由落体加速度，重力加速度，g）（单位m/s²）自由落体在真空中的加速度，在海平面处的平均值约为9.81m/s²。 |
| Coupling | 耦合 |
A detachable mechanism forming a joint. A connector of two components of a joint. 1. Any mechanical fastening connecting two or more shafts, or parts of a mechanism, in order to transmit power. 2. A device for connecting two vehicles. 一种形成关节的可拆卸机构。关节的两个组件的连接器。1.连接两个或多个轴或机构部件的任何机械紧固件，以传递动力。2.连接两辆车的装置。 |
| 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。 |
| U-bolt | U型螺栓 |
A rod threaded at both ends and bent into a U-shape. It is used for clamping. An externally threaded fastener bent in the shape of the letter U and with both ends threaded. 两端有螺纹并弯曲成U形的杆。用于夹紧。一种外螺纹紧固件，弯曲成字母U的形状，两端带有螺纹。 |
| Wave spring | 波形弹簧 |
A type of compression spring, similar to a coil spring, but made of strip shaped into waves around the circumference. 一种压缩弹簧，类似于螺旋弹簧，但由沿圆周成波浪形的条状物制成。 |
| Spring load (Unit N) | 弹簧载荷（单位：N） |
A load exerted on a component by bending, compressing, extending, or twisting an attached spring. Mechanical energy stored in the spring can be released if any constraints on the component are removed. 通过弯曲、压缩、延伸或扭转连接的弹簧而施加在部件上的载荷。如果部件上的任何约束被移除，则可以释放弹簧中存储的机械能。 |
| Roots blower | 罗茨鼓风机 |
(rotary-piston blower) A positive-displacement gas compressor with two meshing lobed rotors that rotate within a close-fitting casing. Commonly used as a supercharger. （旋转活塞鼓风机）一种容积式气体压缩机，具有两个啮合的凸角转子，在紧密配合的外壳内旋转。通常用作增压器。 |
| 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 |
| Salt-velocity meter | 盐速计 |
A volume flow meter based on detecting the transit time for a small quantity of salt or radioactive isotope in a flow by measuring electrical conductivity or radiation level. 一种体积流量计，通过测量电导率或辐射水平来检测流量中少量盐或放射性同位素的渡越时间。 |
| Blue brittleness | 蓝色脆性 |
Anomalous loss of ductility when quenched steels are tempered in the range 250–350°C (temperatures that produce blue tints on the surface of components). Brittleness exhibited by some steels after being heated to some temperature within the range of about 205 to 370 °C (400 to 700 °F), particularly if the steel is worked at the elevated temperature. Killed steels are virtually free of this kind of brittleness. 当淬火钢在250–350°C范围内回火（在部件表面产生蓝色色调的温度）时，延展性异常损失。某些钢在加热到约205至370°C（400至700°F）范围内的某个温度后表现出脆性，特别是在高温下加工钢时。镇静钢几乎没有这种脆性。 |
| Vacuum annealing | 真空退火 |
Annealing carried out at subatmospheric pressure. 在低于大气压的压力下进行退火。 |
| Critical compression ratio | 临界压缩比 |
1. The compression ratio for incipient knock of hydrocarbon fuels as determined in a variable-compression single-cylinder piston engine. 2. The compression ratio at which an air–fuel mixture will spontaneously ignite due to the temperature increase produced. 1.在可变压缩单缸活塞发动机中确定的烃类燃料初期爆震的压缩比。2.空气-燃料混合物由于产生的温度升高而自燃的压缩比。 |
| Columnar structure | 柱状结构 |
A coarse structure of parallel elongated grains formed by unidirectional growth, most often observed in castings, but sometimes in structures resulting from diffusional growth accompanied by a solid-state transformation. 由单向生长形成的平行细长晶粒的粗略结构，最常见于铸件中，但有时也出现在伴随固态转变的扩散生长产生的结构中。 |
| Clevis joint | U形接头 |
A joint formed by two parallel cantilever beams pressed upon a component between the beams. 由两个平行悬臂梁压在梁之间的部件上形成的接头。 |
| Engine emissions | 发动机排放 |
(exhaust emissions) The pollutants contained in the exhaust gases from an internal-combustion engine. （废气排放）内燃机废气中所含的污染物。 |
| Fatigue limit | 疲劳极限 |
The maximum stress that presumably leads to fatigue fracture in a specified number of stress cycles. The value of the maximum stress and the stress ratio also should be stated. Compare with endurance limit. 在指定数量的应力循环中可能导致疲劳断裂的最大应力。还应说明最大应力值和应力比。与耐力极限比较。 |
| DTI | DTI |
Direct tension indicator. A fastener used primarily in the structural steel industry, designed to indicate that a certain minimum amount of tension has been developed in the fastener during assembly. 直接张力指示器。一种主要用于结构钢行业的紧固件，旨在表明在装配过程中紧固件中产生了一定的最小张力。 |
| 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。 |
| 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。 |
| Half hard | 半硬化回火 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength about mid-way between that of dead soft and full hard tempers. 非铁合金和某些铁合金的一种回火，其特点是抗拉强度介于完全软回火和完全硬回火之间。 |
| Kilocalorie | 千卡 |
(Cal, kg-cal, kilogram-calorie, large calorie) An obsolete (i.e. non-SI) unit of energy equal to 1 000 cal. （卡，千克卡，千克卡路里，大卡路里）一种已被淘汰的（即非国际单位制）能量单位，等于1000卡。 |
| ASME | ASME |
The American Society of Mechanical Engineers. 美国机械工程师学会。 |
| Slip line | 滑移线 |
The trace of the slip plane on a viewing surface; the trace is usually observable only if the surface has been polished before deformation. The usual observation on metal crystals (under the light microscope) is of a cluster of slip lines known as a slip band. 滑动平面在观察表面上的轨迹；只有在变形前对表面进行抛光，才能观察到痕迹。通常对金属晶体的观察（在光学显微镜下）是一组称为滑移带的滑移线。 |
| Relative density | 相对密度 |
(specific gravity) The ratio of the density of a substance to that of a reference substance, such as water for liquids and solids, and dry air for gases. （比重）物质密度与参考物质密度之比，如液体和固体为水，气体为干燥空气。 |
| 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。 |
| Graphitization | 石墨化 |
Formation of graphite in iron or steel. Where graphite is formed during solidification, the phenomenon is called primary graphitization; where formed later by heat treatment, secondary graphitization. 在铁或钢中形成石墨。在凝固过程中形成石墨的现象称为一次石墨化；后来通过热处理，形成二次石墨化。 |
| 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。 |
| Biomechanics | 生物力学 |
The application of mechanical-engineering principles, including thermodynamics, fluid mechanics, and solid mechanics together with materials engineering, to biological systems. 机械工程原理（包括热力学、流体力学和固体力学以及材料工程）在生物系统中的应用。 |
| Cap nut | 盖型螺母 |
A nut with a blind threaded hole, for example a dome nut to cover the end of a bolt. 带有盲螺纹孔的螺母，例如用于覆盖螺栓末端的圆顶螺母。 |
| Secondary stresses (Unit Pa) | 二次应力（单位Pa） |
Stresses different from those induced by the major loading but nevertheless resulting from the major loads; for example, the hoop stresses that occur around the circumference of barrelled compression testpieces and forgings. 与主要荷载引起的应力不同，但主要荷载产生的应力；例如，桶装压缩试件和锻件周围产生的环向应力。 |
| 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）。 |
| Socket head | 凹头 |
Screw head having a hexagonal or other form of recessed socket in the head so that the screw can be turned with a wrench or key, as a hexagon key. 螺钉头上有六角或其他形式的凹座，可以用扳手或钥匙（如六角钥匙）转动螺钉。 |
| Die screw | 模具螺丝 |
Tool used when threading cylindrical pieces beyond the capacity of a die plate. 对超出模板容量的圆柱件进行螺纹加工时使用的工具。 |
| Strain aging | 应变时效 |
The changes in ductility, hardness, yield point, and tensile strength that occur when a metal or alloy that has been cold worked is stored for some time. In steel, strain aging is characterized by a loss of ductility and a corresponding increase in hardness, yield point, and tensile strength. 已冷加工的金属或合金在储存一段时间后发生的延展性、硬度、屈服点和抗拉强度的变化。在钢中，应变时效的特点是延性损失，硬度、屈服点和抗拉强度相应增加。 |
| Free ferrite | 游离铁氧体 |
Ferrite that is formed directly from the decomposition of hypoeutectoid austenite during cooling, without the simultaneous formation of cementite. Also proeutectoid ferrite. 在冷却过程中亚共析奥氏体分解直接形成的铁素体，没有同时形成渗碳体。也是先共析铁氧体。 |
| Teeth | 齿 |
The projecting elements on gears, cutting tools, etc. 齿轮、刀具等上的突出元件。 |
| Ductile crack propagation | 延性裂纹扩展 |
Slow crack propagation that is accompanied by noticeable plastic deformation and requires energy to be supplied from outside the body. 缓慢的裂纹扩展，伴随着明显的塑性变形，需要从外部提供能量。 |
| Hardness | 硬度 |
A measure of the resistance of a material to surface indentation or abrasion; may be thought of as a function of the stress required to produce some specified type of surface deformation. There is no absolute scale for hardness; therefore, to express hardness quantitatively, each type of test has its own scale of arbitrarily defined hardness. Indentation hardness can be measured by Brinell hardness test, Rockwell hardness test, Vickers hardness test, Knoop hardness test, and the Scleroscope hardness test. The ability of a ductile material to resist permanent deformation. It is a measure of plastic flow properties determined principally by indentation testing, but scratch hardness and rebound hardness are also employed. hardness scales The different measures of hardness given by different tests, such as indentation pressure in the Brinell and in the Vickers hardness tests, and the different Rockwell hardness numbers. 测量材料对表面压痕或磨损的阻力；可以认为是产生某些特定类型的表面变形所需的应力的函数。硬度没有绝对刻度，因此为了定量表示硬度，每种类型的试验都有自己的任意定义硬度等级。压痕硬度可通过布氏硬度试验、洛氏硬度试验，维氏硬度试验和努氏硬度试验以及硬化镜硬度试验进行测量。延展性材料具有抵抗永久变形的能力，它是主要通过压痕测试确定的塑性流动性能的量度，也使用划痕硬度和回弹硬度。硬度标度不同试验给出的不同硬度测量值，如布氏硬度试验和维氏硬度试验中的压痕压力，以及不同的洛氏硬度值。 |
| Crossed threads | 交叉螺纹 |
When the axis of a nut offered up to a bolt is not aligned with the axis of a bolt (or a screw to a threaded member), it may be possible for the threads to engage incorrectly and even for the nut or screw to advance a turn or more, but ultimately the misaligned threads become locked together. Forcing the nut in such circumstances may irretrievably damage the threads on both. 当提供给螺栓的螺母的轴线与螺栓（或螺纹构件的螺钉）的轴线不对齐时，螺纹可能会错误接合，甚至螺母或螺钉会提前一圈或更多，但最终未对齐的螺纹会锁定在一起。在这种情况下强行拧入螺母可能会对两侧的螺纹造成无法修复的损坏。 |
| Clamping force | 夹紧力 |
The equal and opposite forces which exist at the interface between two joint members. The clamping force is created by tightening the bolts, but is not always equal to the combined tension in the bolts. Hole interference problems, for example, can create a difference between clamping force and bolt loads. 存在于两个连接构件之间的界面处的相等和相反的力。夹紧力是通过拧紧螺栓产生的，但并不总是等于螺栓中的组合张力。例如，孔干涉问题可能会在夹紧力和螺栓载荷之间产生差异。 |
| Tare weight (Unit N) | 皮重（单位N） |
The weight of an empty container. 空容器的重量。 |
| 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。 |
| Tensile strength (Unit Pa) | 抗拉强度（单位Pa） |
In tension testing, the ratio of maximum load to original cross-sectional area. Also known as ultimate strength. The resistance that a material offers to tensile stress. It is defined as the smallest tensile stress required to break the body. (ultimate strength, ultimate tensile strength, UTS, Rm, Rm) The nominal or engineering stress given by the maximum load in a tension test divided by the original cross-sectional area of the specimen. The maximum load could be the fracture load for a brittle material, but for a ductile material it is usually taken as the load at which necking begins, beyond which the load falls. 在拉伸试验中，最大载荷与原始横截面积之比。也称为极限强度。材料对拉伸应力的抵抗力。它被定义为破坏主体所需的最小拉伸应力。（极限强度、极限抗拉强度、UTS、Rm、Rm）拉伸试验中最大载荷除以试样原始横截面积得出的标称或工程应力。对于脆性材料，最大载荷可以是断裂载荷，但对于韧性材料，最大荷载通常被视为颈缩开始时的载荷，超过该载荷时，载荷下降。 |
| Tab washer (lock washer) | 止动垫圈（锁紧垫圈） |
A washer with one or more protruding tabs which can be bent in such a way that a nut or bolt head is prevented from becoming loose. 一种垫圈，具有一个或多个突出凸耳，可弯曲以防止螺母或螺栓头松动。 |
| 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。 |
| 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。 |
| Continuous-type furnace | 连续式炉 |
A furnace used for heat treating materials that progress continuously through the furnace, entering one door and being discharged from another. See belt furnac, direct-fired tunnel-type furnac, rotary retort furnace, shaker-hearth furnace. 一种用于热处理材料的炉子，该炉子连续通过炉子，进入一个门并从另一个门排出。参见带式高炉、直燃隧道式高炉、旋转罐式炉、振动炉。 |
| Thermal energy (heat energy) (Unit J) | 热能（单位：J） |
The sensible and latent forms of internal energy. 内能的感知和潜在形式。 |
| 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。 |
| 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”。 |
| 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。 |
| 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。 |
| Actual cubic feet per minute | 实际立方英尺每分钟 |
(acfm) An obsolete (i.e. non-SI) measure of volumetric flow rate; the volume of a gas flowing per minute at actual operating pressure and temperature, as opposed to the corresponding volume flow rate at STP. （acfm）已被淘汰的（即非SI）体积流量测量；在实际工作压力和温度下每分钟流动的气体体积，与STP下的相应体积流量相反。 |
| Endurance | 耐力 |
The capacity of a material to withstand repeated application of stress. 材料承受反复施加应力的能力。 |
| Ion carburizing | 离子渗碳 |
A method of surface hardening in which carbon ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma carburizing or glowdischarge carburizing. 一种表面硬化方法，利用高压电能将碳离子在真空中扩散到工件中。与等离子渗碳或辉光放电渗碳同义。 |
| 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。 |
| Bright nitriding | 光亮氮化 |
Nitriding in a protective medium to prevent discoloration of the bright surface. 在保护介质中氮化，以防止光亮表面变色。 |
| Coalescence | 聚结 |
Growth of grains at the expense of the remainder by absorption or the growth of a phase or particle at the expense of the remainder by absorption or reprecipitation. 通过吸收以牺牲剩余为代价的晶粒的生长或以通过吸收或再沉淀为代价的以剩余为代价的相或颗粒的生长。 |
| Elasticity | 弹性 |
The property of a material by virtue of which deformation caused by stress disappears on removal of the stress. A perfectly elastic body completely recovers its original shape and dimensions after release of stress. 一种材料的特性，通过这种特性，由应力引起的变形在去除应力后消失。完全弹性体在应力释放后完全恢复其原始形状和尺寸。 |
| Fatigue | 疲劳 |
The phenomenon leading to fracture under repeated or fluctuating stresses having a maximum value less than the ultimate tensile strength of the material. Fatigue failure generally occurs at loads that, applied statically, would produce little perceptible effect. Fatigue fractures are progressive, beginning as minute cracks that grow under the action of the fluctuating stress. A term referring, in components and structures subjected to either random or cyclic periodically-varying loads, to a progressive reduction in strength leading to failure at stresses lower than those that cause failure under monotonic loading. Variable loads arise from outof-balance machinery and other vibration sources, wind gusts, etc., and a large proportion of service failures is caused by fatigue. Fatigue results from the initiation and slow propagation of cracks. In manufactured components, crack initiation usually occurs at a point of stress concentration. After a period, often of millions of stress cycles, the crack reaches a critical length at which the next peak load causes sudden brittle or ductile fracture. Fracture surfaces resulting from fatigue display characteristic striations or progression marks emanating from the crack initiation site during the slow crack growth period, with a different surface appearance for the final fracture. 在最大值小于材料极限抗拉强度的重复或波动应力下导致断裂的现象。疲劳失效通常发生在静态施加的载荷下，不会产生明显影响。疲劳断裂是渐进性的，从在波动应力作用下生长的微小裂纹开始。在承受随机或周期性变化载荷的部件和结构中，指强度逐渐降低，导致在低于单调载荷下导致失效的应力下发生失效的术语。可变负载由失衡的机械和其他振动源、阵风等引起，大部分故障是由疲劳引起的。疲劳是裂纹萌生和缓慢扩展的结果。在制造部件中，裂纹萌生通常发生在应力集中点。在一段时间（通常是数百万次应力循环）后，裂纹达到临界长度，此时下一个峰值载荷会导致突然脆性或韧性断裂。疲劳产生的断裂表面在缓慢裂纹扩展期间显示出从裂纹萌生部位发出的特征条纹或进展标记，最终断裂的表面外观不同。 |
| 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。 |
| Bolt stress (Unit Pa) | 螺栓应力（单位Pa） |
The axial tensile stress induced in a bolt by tightening. 通过拧紧在螺栓中产生的轴向拉应力。 |
| 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%。 |
| 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。 |
| Coefficient of friction (μ) | 摩擦系数（μ） |
(coefficient of kinetic friction, coefficient of sliding friction, friction coefficient, μ) The ratio of the frictional force F to the normal force N between two surfaces in contact, i.e. μ = F/N. Static friction is when there is no relative sliding; kinetic friction when there is. For structural components sliding on one another, the coefficient of friction is the ratio of the force causing the sliding to the force perpendicular to the sliding component surfaces. The coefficient of friction is dimensionless with values between zero and one. The number characterising the force necessary to slide or roll one material along the€surface of another. If an object has a weight N and the coefficient of friction is μ, then the force F necessary to move it without acceleration along a level surface is F = μN. The coefficient of static friction determines the force necessary to initiate movement; the coefficient of kinetic friction determines the force necessary to maintain movement. Kinetic friction is usually smaller than static friction. （动摩擦系数、滑动摩擦系数、摩擦系数，μ）两个接触表面之间摩擦力F与法向力N的比值，即μ=F/N。静摩擦是指没有相对滑动时；有摩擦时的动摩擦。对于相互滑动的结构部件，摩擦系数是引起滑动的力与垂直于滑动部件表面的力的比值。摩擦系数是无量纲的，其值介于0和1之间。代表一种材料沿另一种材料的表面滑动或滚动所需的力的数字。如果一个物体的重量为N并且摩擦系数为μ，那么在没有加速度的情况下沿水平表面移动它所需的力F为F=μN。静摩擦系数决定了启动运动所需的力；动摩擦系数决定了保持运动所需的力。动摩擦通常小于静摩擦。两个物体之间的力（F）与将这些物体压在一起的法向力（N）的无量纲比：μ（或f）=（F/N）。 |
| Annealing | 退火 |
A generic term denoting a treatment, consisting of heating to and holding at a suitable temperature followed by cooling at a suitable rate, used primarily to soften metallic materials, but also to simultaneously produce desired changes in other properties or in microstructure. 一个通用术语，表示一种处理，包括加热并保持在合适的温度，然后以合适的速率冷却，主要用于软化金属材料，但也同时产生其他性能或微观结构的所需变化。 |
| 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。 |
| Alloying element | 合金元素 |
Component added deliberately with the aim of improving the properties of an alloy. Alloying elements can affect the existence range of equilibrium phases present in an unalloyed material, or lead to the occurrence of new phases, or both. In addition, alloying elements strongly affect the kinetics of phase transformations and thus the microstructure formation in alloyed materials. 为改善合金性能而有意添加的成分。合金元素可以影响非合金材料中存在的平衡相的存在范围，或导致新相的出现，或两者兼而有之。此外，合金元素强烈影响相变动力学，从而影响合金材料的微观结构形成。 |
| Creep–time relations | 蠕变时间关系 |
Algebraic or numerical relations between creep strain and time at constant stress. 恒定应力下蠕变应变与时间之间的代数或数值关系。 |
| 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。 |
| 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。 |
| Toothed belt | 齿带 |
A flat belt, typically of a reinforced-rubber material, with transverse teeth that engage with teeth on a wheel or pulley. 一种扁平皮带，通常由增强橡胶材料制成，带有横向齿，与车轮或皮带轮上的齿啮合。 |
| Acoustic separation | 声学分离 |
(Unit m) The separation of particles in a fluid using standing acoustic waves, typically ultrasound, to drive them to nodal points (acoustic particle concentration). （单位m）使用驻声波（通常是超声波）将流体中的粒子分离，以将它们驱动到节点（声学粒子浓度）。 |
| Spherical washer | 球面垫圈 |
A washer whose upper surface is semispherical. Used with a nut whose contact face is also semispherical. Reduces bending stress in a bolt or stud, by allowing some self-alignment and some compensation for nonparallel joint surfaces or Angularity. 上表面为半球形的垫圈。与接触面也是半球形的螺母一起使用。减少螺栓或螺柱中的弯曲应力，允许一些自对准，并对不平行的接头表面或角度进行一些补偿。 |
| Torsion bar | 扭杆 |
A metal bar designed to act as an elastic spring when torque is applied. 当施加扭矩时用作弹性弹簧的金属棒。 |
| 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。 |
| Standard deviation (σ) | 标准偏差（σ） |
A statistical term used to quantify the Scatter in a set of data points. If the standard deviation is small, most of the data points are ‘‘nearly equal.’’ A large deviation means less agreement. The most usual measure of the dispersion of observed values or results expressed as the positive square root of the variance. The square root of variance, a measure of the spread of data about the mean value. 用于量化一组数据点中分散度的统计术语。如果标准偏差很小，则大多数数据点“几乎相等”大的偏差意味着更少的一致性。观测值或结果离散度的最常用度量，表示为方差的正平方根。方差的平方根，衡量平均值的数据分布。 |
| Structure | 结构体 |
An assembly, usually load bearing, of connected (pinned, riveted, screwed, bolted, welded, etc.) components, such as bars, tubes, beams, and plates. 由连接（销接、铆接、螺纹连接、螺栓连接、焊接等）部件组成的组件，通常为承重组件，如杆、管、梁和板。 |
| 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。 |
| Austenite | 奥氏体 |
A solid solution of one or more elements in face-centered cubic iron. Unless otherwise designated (such as nickel austenite), the solute is generally assumed to be carbon. Solid solution of alloying elements and/or carbon in γ-Fe. It is named after British metallurgist W. C. Roberts-Austen. 一种或多种元素在面心立方铁中的固溶体。除非另有说明（如镍奥氏体），溶质通常假定为碳。合金元素和/或碳在γ-Fe中的固溶体。它以英国冶金学家WCRoberts-Austen的名字命名。 |
| Annealing twin | 退火孪晶 |
A twin form in a crystal during recrystallization. 重结晶过程中晶体中的孪晶形式。 |
| 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。 |
| 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。 |
| Hardness test | 硬度测试 |
1. Any of various tests in which different hard indenters are forced into the surface of a solid under different loads to give permanent impressions, the pressure to cause which being called the hardness. The Brinell test employs a spherical indenter; the Vickers test a square-based pyramid. The relation between indentation hardness H and uniaxial yield stress Y is approximately H = (2.5 ~ 3.0)Y. Originally hardnesses were given in kg/mm² but now are often given in Pa. 2. The tests for scratch and file hardness relate either to one material being able to mark another (Mohs hardness scale for minerals), or to the size of groove produced by a rigid indenter slid under load across a surface. 3. Rebound hardness concerns the height of rebound of a dropped indenter, or an indenter at the end of a pivoted arm, having struck a surface. 1.任何一种试验，其中不同的硬压头在不同载荷下压入固体表面，以产生永久压痕，所产生的压力称为硬度。布氏试验采用球形压头；维氏硬度测试是一个方形金字塔。压痕硬度H与单轴屈服应力Y之间的关系约为H=（2.5~3.0）Y。最初硬度以kg/mm²为单位，但现在通常在Pa.2中给出。划痕和锉刀硬度测试要么与一种材料能够标记另一种材料（矿物的莫氏硬度标度）有关，要么与刚性压头在表面上滑动产生的凹槽大小有关。3.回弹硬度涉及掉落压头或旋转臂端部压头撞击表面后的回弹高度。 |
| Activation energy | 活化能 |
(Ea, U) (Unit kJ/mol) The minimum energy for a chemical reaction to occur or for processes such as diffusion to take place in crystals. （Ea, U）（单位kJ/mol）发生化学反应或在晶体中发生扩散等过程的最小能量。 |
| Degradation | 降解 |
The reduction with time of the physical properties of a material. 材料的物理性质随时间的减少。 |
| Pressure storage tank | 压力贮存器 |
(pressure vessel) A closed container for storing gases or volatile liquids, such as liquefied gases, at pressures significantly above atmospheric pressure. Such tanks are commonly cylindrical with domed ends, spherical, spheroidal, torispherical or hemispherical. （压力容器）密闭容器：在大气压以上的压力下储存气体或挥发性液体，如液化气体的密闭容器。此类贮存器通常为圆柱形，具有半球形端部、球形、球面或半球形。 |
| Aerated bath nitriding | 空气搅拌液体渗氮法 |
A type of liquid nitriding in which air is pumped through the molten bath creating agitation and increased chemical activity. 一种液体氮化，其中空气被泵入熔池，产生搅拌并增加化学活性。 |
| Pitch-circle diameter (Unit m) | 节圆直径（单位：m） |
The diameter of the circle (the pitch circle) centred on a component’s axis, around which holes or bolts are equally spaced. 以部件轴为中心的圆（节圆）的直径，孔或螺栓围绕其等距分布。 |
| Tightness parameter | 密封参数 |
A dimensionless parameter which defines the mass leakage of a gasket as a functionof contained pressure and a contained fluid constant. 一种无量纲参数，将垫圈的质量泄漏定义为所含压力和所含流体常数的函数。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Radial marks | 径向标记 |
Lines on a fracture surface that radiate from the fracture origin and are visible to the unaided eye or at low magnification. Radial lines result from the intersection and connection of brittle fractures propagating at different levels. Also known as shear ledges. 断裂表面上的线，从断裂起点辐射，肉眼可见或在低放大率下可见。径向线是在不同层面上传播的脆性断裂相交和连接的结果。也称为剪切壁架。 |
| Speed of rotation (N) | 转速（N） |
(Unit rps or rpm) For an object rotating about a fixed axis, the speed of rotation is the number of turns (revolutions) of the object per unit time. It is equal to the angular velocity Ω (or ω) (unit rad/s) divided by 2π. （单位rps或rpm）对于绕固定轴旋转的物体，旋转速度是物体每单位时间的转数。它等于角速度Ω（或ω）（单位rad/s）除以2π。 |
| Auxetic materials | 拉胀材料 |
Those man-made materials for which Poisson’s ratio is negative, so that the cross section expands when subjected to a longitudinal tensile stress and contracts when subjected to a longitudinal compressive stress. 泊松比为负的人造材料，其横截面在受到纵向拉应力时会膨胀，在受到纵向压应力时会收缩。 |
| Maximum allowable operating pressure (Unit Pa) | 最大允许使用压力（单位Pa） |
The highest pressure at which any pressure system may be operated, usually 10 to 20% below the maximum allowable working pressure. 任何压力系统可运行的最高压力，通常比最大允许工作压力低10%至20%。 |
| Creep fatigue | 蠕变疲劳 |
The effects of combined creep and fatigue at high homologous temperatures in metals, and in other materials such as polymers having time-dependent behaviour. 金属和其他材料（例如具有时间相关行为的聚合物）在高同源温度下的组合蠕变和疲劳的影响。 |
| Wing | 翼 |
A relatively long and thin body with a cross section designed to produce lift when there is motion relative to a fluid. The principal applications are to aircraft and highperformance motor vehicles. 一种相对长而薄的物体，其横截面设计用于在相对于流体运动时产生升力。主要应用于飞机和高性能机动车辆。 |
| 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。 |
| 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。 |
| 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。 |
| Bearing failure | 轴承故障 |
A failure that occurs in a riveted or bolted joint when the transverse load divided by the bearing area results in a stress that leads to permanent plastic deformation. 当横向载荷除以承载面积产生导致永久塑性变形的应力时，铆接或螺栓连接中发生的失效。 |
| Gage length | 标距 |
The original length of the portion of a specimen over which strain, change of length, or other characteristics are determined. 确定应变、长度变化或其他特性的试样部分的原始长度。 |
| True stress (σ) (Unit Pa) | 真应力（σ）（单位Pa） |
The value obtained by dividing the load applied to a member at a given instant by the cross-sectional area over which it acts. Compare with engineering stress. The applied load on a test specimen divided by the current cross-section area over which it acts. σ = s expε where s is the engineering stress given by the applied load divided by the original cross-section area over which it acts, and ε is the true strain. 通过将给定时刻施加在构件上的荷载除以其作用的横截面积而获得的值。与工程应力相比。施加在试样上的荷载除以其作用的当前横截面积。σ=s expε，其中s是由施加荷载除以其作用的原始横截面面积得出的工程应力，ε是真实应变。 |
| Brittle | 脆性材料 |
A brittle material is one that breaks, often suddenly, with no permanent deformation. Examples of brittle materials are some cast irons, glass, concrete, and some plastics. A bolt is said to be brittle if it will break when stretched only a small amount past its yield point. 脆性材料通常会突然断裂，不会产生永久变形。脆性材料的例子有一些铸铁、玻璃、混凝土和一些塑料。如果螺栓在拉伸时仅超过其屈服点一小部分就会断裂，则称其为脆性螺栓。 |
| 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。 |
| Least count | 最小计数 |
The smallest value that can be read from an instrument having a graduated scale. Except on instruments provided with a vernier, the least count is that fraction of the smallest division which can be conveniently and reliably estimated; this fraction is ordinarily one-fifth or one-tenth, except where the graduations are very closely spaced. 可从具有刻度尺的仪器中读取的最小值。除配备游标的仪器外，最小计数是可以方便可靠地估计的最小除法的分数；这个分数通常是五分之一或十分之一，除非刻度间隔非常近。 |
| 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）。 |
| 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。 |
| Laser hardening | 激光硬化 |
A surface-hardening process which uses a laser to quickly heat a surface. Heat conduction into the interior of the part will quickly cool the surface, leaving a shallow martensitic layer. Hardening of steel by a moving CO2 or Nd:YAG laser beam focussed down to a few mm in diameter. A point in the surface of an object is rapidly heated into the austenite range and then rapidly cooled to form tempered martensite. 一种使用激光快速加热表面的表面硬化工艺。进入零件内部的热传导将快速冷却表面，留下浅马氏体层。通过移动CO2或Nd:YAG激光束使钢硬化，激光束聚焦至直径几毫米。物体表面的一点迅速加热到奥氏体范围，然后迅速冷却，形成回火马氏体。 |
| Imperial system | 英制单位体系 |
The units of measurement developed in the UK. Formerly known as the fps system, which is an abbreviation for the ‘foot-pound-second system of units. 英国开发的计量单位。以前称为fps系统，是“英尺-磅-秒（foot-pound-second）单位制”的缩写。 |
| 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。 |
| Bearing test | 轴承测试 |
A method of determining the response to stress (load) of metal products that are subjected to riveting, bolting, or a similar fastening procedure. The purpose of the test is to determine the bearing strength of the material and to measure the bearing stress versus the deformation of the hole created by a pin or rod of circular cross section that pierces the sheet perpendicular to the surface. 一种确定经受铆接、螺栓连接或类似紧固程序的金属产品对应力（载荷）的响应的方法。测试的目的是确定材料的承载强度，并测量承载应力与由垂直于表面刺穿板材的圆形横截面的销或杆产生的孔的变形。 |
| Clearance | 间距 |
(Unit m or μm) 1. The distance (if any) between mating components in an assembly. 2. The distance between two moving parts, or a moving part and stationary part, in a machine (e.g. the gap between a piston and a cylinder head). 3. With threads, the major clearance is the distance between the design form at the root of an internal thread and the crest of its mating external thread; the minor clearance is the corresponding dimension between the crest of an internal thread and the root of the external thread. （单位m或μm）1.装配体中配合组件之间的距离（如果有）。2.机器中两个运动部件之间的距离，或运动部件和静止部件之间的距离（例如活塞和气缸盖之间的间隙）。3.带螺纹时，主要间隙是内螺纹根部的设计形状与其配合的外螺纹牙顶之间的距离；小间隙是内螺纹牙顶和外螺纹牙根之间的对应尺寸。 |
| Zero time | 零时 |
The time when the given loading or constraint conditions are initially obtained in creep or stressrelaxation tests, respectively. 分别在蠕变或应力松弛试验中初始获得给定载荷或约束条件的时间。 |
| Joint diagrams | 接合处关系图 |
Mathematical diagrams which illustrate the forces on and deflections of fasteners and joint members. 说明紧固件和连接件上的力和变形的数学图。 |
| 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。 |
| Quench-age embrittlement | 淬火时效脆化 |
Embrittlement of low-carbon steels resulting from precipitation of solute carbon at existing dislocations and from precipitation hardening of the steel caused by differences in ferrite at different temperatures. Quenchage embrittlement usually is caused by rapid cooling of the steel from temperatures slightly below Ac1 (the temperature at which austenite begins to form), and can be minimized by quenching from lower temperatures. 低碳钢的脆化是由于溶质碳在现有位错处的沉淀和铁素体在不同温度下的差异导致的钢沉淀硬化造成的。淬火脆性通常是由钢从略低于Ac1的温度（奥氏体开始形成的温度）快速冷却引起的，可以通过从较低温度淬火来最小化。 |
| Microstrain | 微应变 |
The strain over a gage length comparable to interatomic distances. These are the strains being averaged by the macrostrain measurement. Microstrain is not measurable by currently existing techniques. Variance of the microstrain distribution can, however, be measured by x-ray diffraction. 与原子间距离相当的标距上的应变。这些是通过宏观应变测量得到的平均应变。现有技术无法测量微应变。然而微应变分布的变化可以通过x射线衍射来测量。 |
| Proof stress | 弹性极限应力 |
(1) The stress that will cause a specified small permanent set in a material. (2) A specified stress to be applied to a member or structure to indicate its ability to withstand service loads. （1）在材料中引起规定的小永久变形的应力。（2）施加在构件或结构上的规定应力，以表明其承受工作荷载的能力。 |
| Crack size (a) | 裂纹尺寸（a） |
A lineal measure of a principal planar dimension of a crack. This measure is commonly used in the calculation of quantities descriptive of the stress and displacement fields. In practice, the value of crack size is obtained from procedures for measurement of physical crack size, original crack size, or effective crack size, as appropriate to the situation under consideration. 裂纹主平面尺寸的线性度量。这种测量通常用于计算描述应力场和位移场的量。在实践中，裂纹尺寸的值是通过测量物理裂纹尺寸、原始裂纹尺寸或有效裂纹尺寸的程序获得的，视情况而定。 |
| Preheating | 预热 |
Heating before some further thermal or mechanical treatment. For tool steel, heating to an intermediate temperature immediately before final austenitizing. For some nonferrous alloys, heating to a high temperature for a long time, to homogenize the structure before working. In welding and related processes, heating to an intermediate temperature for a short time immediately before welding, brazing, soldering, cutting, or thermal spraying. 在进一步热处理或机械处理之前加热。对于工具钢，在最终奥氏体化之前立即加热至中间温度。对于一些非铁合金，在工作前长时间加热到高温，以使结构均匀化。在焊接和相关工艺中，在焊接、钎焊、钎焊、切割或热喷涂之前，立即加热到中间温度。 |
| Dynamic hardness | 动态硬度 |
(rebound hardness) The resistance of a material to local indentation by a rapidly-moving rigid indenter. In most practical methods the indenter is allowed to fall under gravity on to the surface of the material when the rebound height is a measure of the dynamic hardness. （回弹硬度）材料对快速移动的刚性压头局部压痕的阻力。在大多数实际方法中，当回弹高度是动态硬度的测量值时，允许压头在重力作用下落在材料表面上。 |
| Impact loads | 冲击载荷 |
Especially severe shock loads such as those caused by instantaneous arrest of a falling mass, shock meeting of two parts (in a mechanical hammer, for example), or by explosive impact, in which there can be an exceptionally rapid build-up of stress. 特别严重的冲击载荷，例如由下落质量的瞬时停止、两部分的冲击碰撞（例如在机械锤中）或爆炸性冲击引起的冲击载荷，其中可能会出现异常快速的应力积聚。 |
| Flat head | 平头 |
Flat top surface and a conical bearing surface. 平顶表面和锥形轴承表面。 |
| Strain | 拉紧 |
The unit of change in the size or shape of a body due to force. Also known as nominal strain. 物体的大小或形状因力而变化的单位。也称为标称应变。 |
| 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。 |
| 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。 |
| 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。 |
| Bearing area | 承载面积 |
The product of the pin (or hole) diameter and specimen thickness in a bearing test. (bearing surface) (Unit m²) The projected area of a hole, such as a rivet hole, that carries a transverse load. 轴承测试中销（或孔）直径和试样厚度的乘积。（承载面）（单位m²）承载横向载荷的孔（例如铆钉孔）的投影面积。 |
| Combined dimensioning | 组合尺寸标注 |
The use of chain dimensioning and parallel dimensioning on the same engineering drawing. 在同一工程图上使用链式尺寸标注和平行标注。 |
| Population | 集合 |
The hypothetical collection of all possible test specimens that could be prepared in the specified way from the material under consideration. Also known as universe. 从所考虑的材料中以规定方式制备的所有可能试样的假设集合。也称为体系。 |
| Erosion | 侵蚀 |
Progressive loss of original material from a solid surface due to mechanical interaction between that surface and a fluid, a multicomponent fluid, or impinging liquid or solid particles. 由于固体表面与流体、多组分流体或撞击液体或固体颗粒之间的机械相互作用，原始材料从固体表面逐渐损失。 |
| Wrist | 腕关节 |
The final three joints on a robot which simulate rotations provided by the human wrist and thus allow orientation of the end effector to which it is attached by the wrist socket. 机器人上的最后三个关节，模拟人类手腕提供的旋转，从而允许其通过手腕插座连接到的末端执行器的方向。 |
| Generator | 发电机 |
1. A machine for converting mechanical energy to electrical energy. 2. (generatrix) A point, line, or surface regarded as moving and so forming a line, a surface, or a volume, respectively. 1.将机械能转化为电能的机器。2.（母线）被认为是运动的点、线或面，因此分别形成一条线、一个面或一个体积。 |
| Radioactive heat (Unit J) | 放射性热（单位J） |
Thermal energy released from the nucleus of an atom such as uranium235 by fission due to the absorption of a neutron. Heat is also produced by radioactive decay. 铀235等原子核因吸收中子而裂变释放的热能。放射性衰变也会产生热量。 |
| 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。 |
| Clip gauge | 夹规 |
A displacement gauge consisting of two thin strain-gauged cantilever arms attached through knife edges to a testpiece to give the load–line displacement in fracture mechanics test pieces, or used as an extensometer in tensile tests. 一种位移计，由两个通过刀刃连接到试件上的薄应变测量悬臂组成，以提供断裂力学试件中的载荷线位移，或用作拉伸试验中的引伸计。 |
| 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。 |
| Checks | 检查 |
Numerous, very fine cracks in a coating or at the surface of a metal part. Checks may appear during processing or during service and are most often associated with thermal treatment or thermal cycling. 涂层中或金属零件表面的许多非常细微的裂纹。在加工或服务期间可能会出现检查，并且通常与热处理或热循环有关。 |
| 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。 |
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