| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Crack length (depth) (a) | 裂纹长度（深度）（a） |
In fatigue and stress corrosion cracking, the physical crack size used to determine the crack growth rate and the stress-intensity factor. For the compact-type specimen, crack length is measured from the line connecting the bearing points of load application. For the center-cracked-tension specimen, crack length is measured from the perpendicular bisector of the central crack. 在疲劳和应力腐蚀裂纹中，用于确定裂纹扩展速率和应力强度因子的物理裂纹尺寸。对于紧凑型试样，裂纹长度从连接载荷施加点的线开始测量。对于中心裂纹拉伸试样，从中心裂纹的垂直平分线测量裂纹长度。 |
| Compressed liquid | 压缩液体 |
A liquid subjected to a pressure greater than the saturation pressure corresponding to its temperature. 承受大于与其温度对应的饱和压力的压力的液体。 |
| 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。 |
| 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。 |
| Burning | 燃烧化 |
(1) Permanently damaging a metal or alloy by heating to cause either incipient melting or intergranular oxidation. See overheating, grain-boundary liquation. (2) In grinding, getting the work hot enough to cause discoloration or to change the microstructure by tempering or hardening. （1）通过加热导致初期熔化或晶间氧化而永久损坏金属或合金。参见过热、晶界液化。（2）在磨削过程中，使工件热到足以引起变色或通过回火或硬化改变微观结构。 |
| 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。 |
| Impact strength 1. (Unit Pa) | 冲击强度1.（单位Pa） |
The stress to cause failure (by yielding or fracture) under conditions of high strain rate. 2. (Unit J) A term sometimes used to describe the energy required to fracture a specimen in a Charpy or Izod impact test even though the unit is not that of strength. 在高应变率条件下导致失效（通过屈服或断裂）的应力。2.（单位J）有时用于描述在夏比或悬臂梁式冲击试验中使样品断裂所需的能量，即使单位不是强度单位。 |
| Semiguided bend | 半导弯曲 |
The bend obtained by applying a force directly to the specimen in the portion that is to be bent. The specimen is either held at one end and forced around a pin or rounded edge, or is supported near the ends and bent by a force applied on the side of the specimen opposite the supports and midway between them. In some instances, the bend is started in this manner and finished in the manner of a free bend. 通过将力直接施加于待弯曲部分中的试样而获得的弯曲。将试样固定在一端，并围绕销或圆边施力，或者在靠近端部的位置支撑试样，并通过施加在试样与支撑件相对的一侧以及两者中间的力进行弯曲。在某些情况下，折弯以此方式开始，然后以自由折弯的方式结束。 |
| Achme thread | Achme螺纹 |
A screw thread having an included angle of 29° and largely used for feed screws on machine tools. 一种夹角为29°的螺纹，主要用于机床上的进给丝杠。 |
| Socket wrench | 套筒扳手 |
A form of spanner with an internally ridged steel socket to fit a nut or the head of a bolt or screw. 扳手的一种形式，带有内脊钢套筒，用于安装螺母或螺栓或螺钉的头部。 |
| Cylinder head | 气缸盖 |
The machined casting, typically of aluminium alloy or cast iron, that fits above the cylinder block of a piston engine and closes off the cylinders. It normally includes part of the combustion chambers and holes for the valves and spark plugs. 活塞式发动机缸体上方的机械铸件，通常由铝合金或铸铁制成，用于封闭气缸。它通常包括燃烧室的一部分以及阀门和火花塞的孔。 |
| Plastic deformation | 塑性变形 |
The permanent (inelastic) distortion of a material under applied stress that strains the material beyond its elastic limit. 材料在施加应力下的永久（非弹性）变形，使材料应变超过其弹性极限。 |
| Captive nut | 松脱螺母 |
A nut attached loosely or rigidly to a sheet member that is too thin to thread and which engages with a cap screw. 松脱地或刚性地连接到薄板构件上的螺母，该螺母太薄而无法拧入，并与带帽螺钉接合。 |
| 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。 |
| Second (s) | 秒（s） |
The SI base unit of time equal to 9 192 631 770 times the period of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom. SI基时间单位等于9192631770倍的辐射周期，对应于铯-133原子基态的两个超精细能级之间的跃迁。 |
| Coaxial | 同轴 |
A term for components having a common axis such as concentric shafts. 具有共同轴线的部件的术语，例如同心轴。 |
| Rotational joint (revolute joint) | 旋转关节 |
In robotics, a single degree-of-freedom joint where the controlled variable is the joint angle. 在机器人技术中，一种单自由度关节，其中受控变量为关节角度。 |
| Constant life diagram | 恒定寿命图 |
A plot of experimentally derived fatigue-life data; perhaps the most complex and complete of the popular charts used to represent such data. 实验得出的疲劳寿命数据图；可能是用于表示此类数据的最复杂和最完整的流行图表。 |
| 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。 |
| Design load (Unit N) | 设计荷载（单位N） |
The greatest load that a component or structure is expected to experience under normal operating conditions. 部件或结构在正常运行条件下预期承受的最大负载。 |
| 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。 |
| 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）。 |
| 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。 |
| Temper embrittlement | 回火脆化 |
Brittleness that results when certain steels are held within, or are cooled slowly through, a certain range of temperature below the transformation range. The brittleness is manifested as an upward shift in ductile-to-brittle transition temperature but only rarely produces a low value of reduction in area in a smooth-bar tension test of the embrittled material. The anomalous reduction in toughness of martensitic stainless steels when tempered in the range 370–600°C. Embrittlement of alloy steels caused by holding within or cooling slowly through a temperature range just below the transformation range. Embrittlement is the result of the segregation at grain boundaries of impurities such as arsenic, antimony, phosphorus, and tin; it is usually manifested as an upward shift in ductile-to-brittle transition temperature. Temper embrittlement can be reversed by retempering above the critical temperature range, then cooling rapidly. 当某些钢保持在低于转变范围的某一温度范围内或缓慢冷却时产生的脆性。脆性表现为延性到脆性转变温度的向上移动，但在脆性材料的平滑棒材拉伸试验中，很少产生较小的面积减小值。马氏体不锈钢在370–600°C范围内回火时的韧性异常降低。合金钢的脆化是由于在低于转变范围的温度范围内保持或缓慢冷却而引起的。脆化是杂质（如砷、锑、磷和锡）在晶界处偏析的结果；它通常表现为韧脆转变温度的上升。回火脆化可以通过在临界温度范围以上重新回火，然后快速冷却来逆转。 |
| Fastener | 紧固件 |
A fastener is a mechanical device for holding two or more bodies in definite positions with respect to each other. 紧固件是一种机械装置，用于将两个或多个物体相对于彼此固定在确定的位置。 |
| 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。 |
| Chain dimensioning | 链条尺寸标注 |
On an engineering drawing, where the end point of one dimension is the starting point for the next. Parallel dimensioning is preferred as chain dimensioning can lead to the accumulation of tolerances. 在工程图纸上，其中一个尺寸的终点是下一个的起点。平行尺寸标注是首选，因为链尺寸标注可能导致公差累积。 |
| Barometer | 气压计 |
An instrument used to measure atmospheric pressure. An instrument for measuring atmospheric pressure. There are two main types – the mercury barometer, and the aneroid barometer. 用于测量大气压力的仪器。有两种主要类型——水银气压计和无液气压计。 |
| Precision | 精确 |
The closeness of agreement between the results of individual replicated measurements or tests. The standard deviation of the error of measurement may be used as a measure of “imprecision.” 单个重复测量或测试结果之间的一致性。测量误差的标准偏差可用作“不精确性”的度量 |
| Electrolyte | 电解质 |
The liquid with which the Electrodes of a battery or Corrosion cell are wetted. 润湿电池或腐蚀电池电极的液体。 |
| Black oxide | 黑色氧化物 |
A black finish on a metal produced by immersing it in hot oxidizing salts or salt solutions. 通过将金属浸入热氧化盐或盐溶液中产生的黑色饰面。 |
| Austenite finish temperature (Af) | 奥氏体完成温度（Af） |
Temperature at which the transformation of martensite into austenite completes upon heating. The same designation is also applied to nonferrous alloys in which martensite transforms into some parent phase. 加热时马氏体转变为奥氏体的温度。相同的名称也适用于马氏体转变为某些母相的有色合金。 |
| Union (union joint) | 活接头 |
A threaded pipe fitting that allows two pipes to be connected anddetached without the need for either to be rotated, and without damaging the pipe ends. 一种螺纹管件，允许连接和拆卸两个管道，而无需旋转任何一个管道，且不会损坏管道端部。 |
| Deviation | 偏差 |
The difference between the actual value and the desired value of a controlled variable. 受控变量的实际值与期望值之间的差值。 |
| Diffusion coating | 扩散涂层 |
Coating on metal for corrosion- and/or oxidation-resistance. Coatings are produced by heating a metal in contact with an alloy in powder, liquid, or gaseous form at elevated temperature such that atoms of the coating diffuse into the substrate. Examples include chromium, aluminium, or silicon on substrates such as nickel-based superalloys, steels, and refractory metals. 金属上的防腐和/或抗氧化涂层。涂层是通过在高温下加热与粉末、液体或气体形式的合金接触的金属，从而使涂层的原子扩散到基体中而产生的。实例包括基底上的铬、铝或硅，如镍基高温合金、钢和耐火金属。 |
| Working stress (Unit Pa) | 工作应力（单位Pa） |
The stress under which a component or structure is designed to operate under normal conditions. 部件或结构设计为在正常条件下运行的应力。 |
| Corrosion failure | 腐蚀失效 |
1. The failure of a component or structure after corrosion has reduced the load-bearing area to an unsupportable level. 2. A situation in which a mechanism cannot function owing to corrosion products preventing free movement at joints. 1、部件或结构在腐蚀后失效，使承重面积减少到无法支撑的程度。2.由于腐蚀产物阻止关节处的自由运动，导致机构无法运行的情况。 |
| Ablative materials | 烧蚀材料 |
Materials, especially coating materials, designed to provide thermal protection to a body in a fluid stream through the loss of mass. 材料，尤其是涂层材料，旨在通过质量损失为流体流中的物体提供热保护。 |
| Hydraulics | 液压系统 |
The study of water flow in open channels (including canals, rivers, etc.), water-supply, drainage, and irrigation systems. 研究明渠（包括运河、河流等）、供水、排水和灌溉系统中的水流。 |
| Plane strain | 平面应变 |
The stress condition in linear-elastic fracture mechanics in which there is zero strain in a direction normal to both the axis of applied tensile stress and the direction of crack growth (i.e., parallel to the crack front); most nearly achieved in loading thick plates along a direction parallel to the plate surface. Under plane-strain conditions, the plane of fracture instability is normal to the axis of the principal tensile stress. 线弹性断裂力学中的应力条件，其中在垂直于施加拉应力轴和裂纹扩展方向（即平行于裂纹前沿）的方向上存在零应变；最接近于沿平行于板表面的方向加载厚板。在平面应变条件下，断裂失稳平面垂直于主拉应力轴。 |
| Specimen | 样品 |
A test object, often of standard dimensions or configuration, that is used for destructive or nondestructive testing. One or more specimens may be cut from each unit of a sample. 用于破坏性或无损检测的测试对象，通常具有标准尺寸或配置。可以从样品的每个单位切割一个或多个样品。 |
| 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。 |
| Pre-stress | 预应力 |
To induce stresses into a component or structure before it is subjected to operating loads. 在部件或结构承受操作载荷之前，将应力引入部件或结构。 |
| Absorption dynamometer | 吸收式测功机 |
A dynamometer in which input work or power is dissipated by mechanical friction, electrical resistance, hydraulic resistance, etc. 通过机械摩擦、电阻、液压阻力等耗散输入功或功率的测功机。 |
| 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。 |
| Screw extractor | 螺钉拔 |
A device for removing broken-off screws from threaded holes. It resembles a drill with, for broken right-hand threads, a fast (long-pitch) left-hand thread that is driven into a hole drilled in the broken screw, thus untwisting it. 从螺纹孔中去除断裂螺钉的装置。它类似于一个钻头，对于断裂的右螺纹，一个快速（长螺距）的左螺纹被打入在断裂螺钉上钻的孔中，从而将其松开。 |
| 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）。 |
| Compression wave | 压缩波 |
(dilatation wave) In a fluid or a solid, a progressive wave or wavefront that compresses the medium through which it propagates. （膨胀波）在流体或固体中，压缩介质传播的行波或波前。 |
| Guided bend | 导向弯曲 |
The bend obtained by use of a plunger to force the specimen into a die in order to produce the desired contour of the outside and inside surfaces of the specimen. 通过使用柱塞将试样压入模具中获得的弯曲，以产生试样外表面和内表面所需的轮廓。 |
| Wedge | 楔子 |
A short triangular prism whose major surfaces subtend an acute angle, that can be driven between two objects or parts of an object to split, tighten, or secure them, or to widen an opening or raise a heavy object. The acute angle gives a high mechanical advantage. 一种短的三棱镜，其主面对着一个锐角，可在两个物体或物体的一部分之间驱动，以将它们分开、拧紧或固定，或加宽开口或举起重物。锐角具有很高的机械优势。 |
| 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。 |
| mechanical engineering | 机械工业 |
That branch of engineering concerned with energy conversion, stress analysis, vibration, dynamics, and kinematics, especially applied to design (machine design, mechanical-engineering design). 与能量转换、应力分析、振动、动力学和运动学有关的工程分支，尤其适用于设计（机器设计、机械工程设计）。 |
| Trepanning | 开孔 |
Trepanning is a machining process for producing a circular hole or groove in solid stock, or for producing a disk, cylinder, or tube from solid stock, by the action of a tool containing one or more cutters (usually single-point) revolving around a center. 开孔是一种机械加工工艺，通过包含一个或多个围绕中心旋转的刀具（通常为单点）的作用，在实心坯料中制造圆孔或凹槽，或从实心坯料生产圆盘、圆柱体或管。 |
| Dynamics | 动力学 |
The branch of mechanics that deals with objects in motion. Its two main branches are kinematics, which studies motion without regards to its cause, and kinetics, which also takes into account forces that cause motion. 力学中研究运动物体的分支。它的两个主要分支是运动学和动力学，前者研究运动而不考虑其原因，后者也考虑引起运动的力。 |
| Wear | 磨损 |
Damage to a solid surface, generally involving progressive loss of material, due to relative motion between that surface and a contacting surface or substance. The deterioration of a component or structure with time and usage, often impairing the function for which it was designed, owing to abrasion, corrosion, fatigue, friction, etc. during relative motion of parts. The wear factor (K), with unit mm³/N.m, is an empirical dimensional factor that quantifies surface wear due to mechanical frictional contact, and defined by K = /Fs where is the worn volume (in mm³), F is the contact load (in N), and s is the sliding distance (in m). 由于固体表面与接触表面或物质之间的相对运动，对固体表面的损坏，通常涉及材料的渐进损失。部件或结构随时间和使用而劣化，通常由于部件相对运动过程中的磨损、腐蚀、疲劳、摩擦等而损害其设计功能。磨损系数（K），单位为mm³/N.m、 是量化机械摩擦接触导致的表面磨损的经验尺寸因子，由K=/Fs定义，其中是磨损体积（单位：mm³），F是接触载荷（单位：N），s是滑动距离（单位：m）。 |
| Low-E coating | 低辐射涂层 |
(low-emittance coating) A thin metallic or metal-oxide coating on a glass sheet to absorb and reflect infrared radiation. The coating is applied either by a pyrolytic chemical vapour-deposition process (hard coat), or by sputtering (soft coat). （低辐射涂层）玻璃板上的薄金属或金属氧化物涂层，用于吸收和反射红外辐射。通过热解化学气相沉积工艺（硬涂层）或溅射（软涂层）施加涂层。 |
| Total energy (Unit J) | 总能量（单位J） |
The sum of all forms of energy associated with a system, including kinetic, potential, internal, magnetic, chemical, and electrical energy. 与系统相关的所有形式能量的总和，包括动能、势能、内能、磁能、化学能和电能。 |
| Available head (Unit m) | 可用水头（单位米） |
In a hydroelectric power system, the difference between the vertical height of the water level in the supply reservoir above the turbine inlet less the head loss due to friction and fittings in the duct leading to the turbine. 在水力发电系统中，水轮机入口上方供水水库中水位垂直高度之间的差减去由于通向涡轮机的管道中的摩擦和配件造成的水头损失。 |
| Load and resistance factor design | 负载和阻力系数设计 |
A design procedure developed for the AISC by the Research Council on Structural Connections. Assigns uncertainties in the strength of (i.e., resistance of) and in the service loads to be placed on a shear joint to estimate the probable strength of the joint. It is a recently defined alternative to the Allowable stress design procedure. 结构连接研究委员会为AISC制定的设计程序。分配剪切接头的强度（即阻力）和工作荷载的不确定性，以估计接头的可能强度。它是最近定义的容许应力设计程序的替代方案。 |
| 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。 |
| Proportional limit | 比例极限 |
The greatest stress a material is capable of developing without a deviation from straight-line proportionality between stress and strain. 材料能够产生的最大应力不偏离应力和应变之间的直线比例。 |
| Dynamic strain aging | 动态应变时效 |
A behavior in metals in which solute atoms are sufficiently mobile to move toward and interact with dislocations. This results in strengthening over a specific range of elevated temperature and strain rate. 金属的一种特点，其中溶质原子具有足够的移动能力，能够向位错移动并与位错相互作用，会导致在特定的高温和应变速率范围内强化。 |
| Dimensional stability | 尺寸稳定性 |
Ability of a plastic part to retain the precise shape in which it was molded, fabricated, or cast. 塑料零件保持其成型、制造或铸造时的精确形状的能力。 |
| Octane number | 辛烷值 |
(octane rating) A measure of the anti-knock properties of a fuel taken as the percentage by volume of iso-octane in the fuel. （辛烷值）以燃料中异辛烷的体积百分比表示的燃料抗爆性能的量度。 |
| Quarter hard | （1/4H）低硬（回火） |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength aboutmidway between that of dead soft and half 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软态和半硬态之间。 |
| Computer-aided design (CAD) | 计算机辅助设计（CAD） |
Generally, design and calculations performed by computer; more specifically, the use of computer graphics and models to communicate design concepts. Computer-aided design and computer-aided manufacturing (CAD/CAM) is where component dimensions resulting from CAD are passed by electronic means directly to machines for manufacture. 一般由计算机进行设计和计算，更具体地说，使用计算机图形和模型来传达设计概念。计算机辅助设计和计算机辅助制造（CAD/CAM）是由CAD产生的组件尺寸通过电子方式直接传递到机器进行制造。 |
| Hooke’s law | 胡克定律 |
Within the limit of proportionality, the extension of a material is proportional to the applied force. Approximately, it is the relationship between stress and strain in an elastic material when it is stretched. The law states that the stress (force per unit area) is proportional to the strain (a change in dimensions). The law, which holds only approximately and over a limited range, was discovered in 1676 by Robert Hooke. 在比例极限内，材料的延伸与所施加的力成比例。近似地说，它是弹性材料拉伸时应力和应变之间的关系。该定律指出，应力（单位面积的力）与应变（尺寸变化）成比例。该定律仅适用于有限的范围，由罗伯特·胡克于1676年发现。 |
| Absolute expansion | 绝对扩张 |
The true volumetric expansion of a liquid with temperature, after account is taken of any expansion of the container in which it is held. 考虑到容纳液体的容器的任何膨胀后，液体随温度的真实体积膨胀。 |
| 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。 |
| Absolute humidity | 绝对湿度 |
The weight of water vapor in a gadwater vapor mixture per unit volume of space occupied, expressed, for example, in grains or pounds per cubic foot. 单位体积空间占用的水蒸气混合物中水蒸气的重量，例如，以谷物或磅/立方英尺表示。 |
| Stead’s brittleness | 斯特德脆性 |
A condition of brittleness that causes transcrystalline fracture in the coarse grain structure that results from prolonged annealing of thin sheets of low-carbon steel previously rolled at a temperature below about 705 °C (1300 °F). The fracture usually occurs at about 45° to the direction of rolling. 一种脆性状态，导致粗晶结构中发生穿晶断裂，这是由于之前在低于约705°C（1300°F）的温度下轧制的低碳钢薄板经过长时间退火造成的。断裂通常发生在与轧制方向约45°处。 |
| Bolt | 螺栓 |
(machine bolt) A fastener in the form of an externally-threaded cylinder with a head on one end that is inserted through holes in assembled parts that are then held together by a nut tightened on to the thread. A bolt has an unthreaded region below the head so that when located in a hole, transverse loads are borne by two plain cylindrical surfaces in contact. In contrast, use of a machine screw, that has threads all along its length, results in threads bearing against the plain surface of a hole. Officially, a threaded fastener designed to be used with a nut. （机械螺栓）外螺纹圆柱状紧固件：一端有头的紧固件，通过装配零件上的孔插入，然后通过拧紧到螺纹上的螺母固定在一起。螺栓头部下方有一个无螺纹区域，因此当位于孔中时，横向载荷由两个接触的平面圆柱面承担。相反，使用沿其长度具有螺纹的机器螺钉，会导致螺纹支撑在孔的平面上。正式情况下，螺纹紧固件设计用于与螺母一起使用。 |
| Maximum stress-intensity factor (Kmax) | 最大应力强度因子（Kmax） |
The maximum value of the stress-intensity factorin a fatigue cycle. 疲劳循环中应力强度因子的最大值。 |
| Flame hardening | 火焰硬化 |
A process for hardening the surfaces of hardenable ferrous alloys in which an intense flame is used to heat the surface layers above the upper transformation temperature, whereupon the workpiece is immediately quenched. 一种用于硬化可硬化铁合金表面的工艺，其中使用强烈的火焰将表面层加热到转变温度上限以上，然后立即对工件进行淬火。 |
| Radius of bend | 弯曲半径 |
The radius of the cylindrical surface of the pin or mandrel that comes in contact with the inside surface of the bend during bending. For free or semiguided bends to 180° in which a shim or block is used, the radius of bend is one-half the thickness of the shim or block. 在弯曲过程中与弯曲内表面接触的销或心轴的圆柱面半径。对于使用垫片或垫块的180°自由弯曲或半导向弯曲，弯曲半径为垫片或垫板厚度的一半。 |
| Physical testing | 物理测试 |
Methods used to determine the entire range of physical properties of a material. In addition to density and thermal, electrical, and magnetic properties, physical testing methods can be used to assess simple fundamental physical properties such as color, crystalline form, and melting point. 用于确定材料整个物理特性范围的方法。除了密度和热、电、磁特性外，物理测试方法还可用于评估简单的基本物理特性，如颜色、结晶形式和熔点。 |
| 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。 |
| Corrosion cell | 腐蚀电池 |
A natural ‘‘battery’’ formed when two metals having different electrical potentials (an Anode and a Cathode) are connected together in the presence of a liquid (the Electrolyte). 当两种具有不同电势的金属（阳极和阴极）在液体（电解质）存在下连接在一起时形成的天然“电池”。 |
| Stress-strain diagram | 应力-应变图 |
A graph in which corresponding values of stress and strain are plotted against each other. Values of stress are usually plotted vertically(ordinates or y-axis) and values of strain horizontally (abscissas or xaxis). Also known as deformation curve and stress-strain curve. 对应的应力和应变值相对绘制的图表。应力值通常垂直绘制（纵坐标或y轴），应变值水平绘制（横坐标或X轴）。也称为变形曲线和应力-应变曲线。 |
| Newton’s law of viscosity | 牛顿内摩擦定律 |
The shear stress between two parallel layers of fluid is proportional to the velocity of one relative to that of the other, and inversely proportional to the distance between them. The constant of proportionality is the dynamic viscosity μ. For a Newtonian fluid μ is independent of pressure gradient, shear stress, and strain, but may change with temperature and pressure. 两个平行流体层之间的剪切应力与其中一层相对于另一层的速度成正比，与它们之间的距离成反比。比例常数是动态粘度μ。对于牛顿流体，μ与压力梯度、剪切应力和应变无关，但可能随温度和压力而变化。 |
| Scoring | 划痕 |
In tribology, a severe form of wear characterized by the formation of extensive grooves and scratches in the direction of sliding. 在摩擦学中，一种严重的磨损形式，其特征是在滑动方向上形成大面积的凹槽和划痕。 |
| Pneumatic control valve | 气动控制阀 |
(pneumatic valve) A valve in which the position of the valve stem, which varies the open area, is determined by the net force generated by compressed air acting on a diaphragm operating against the force of a compression spring. Depending upon the arrangement of the spring, in the event of air-supply failure, the valve may open or close. （气动阀）一种阀门，其中阀杆的位置随开口面积的变化而变化，由压缩空气作用在隔膜上产生的净力决定，隔膜克服压缩弹簧的力进行操作。根据弹簧的布置，在供气故障的情况下，阀门可以打开或关闭。 |
| Peel strength (Unit N) | 剥离强度（单位：N） |
(peel test) The strength of an adhesive bond between two materials as measured by the force required in a given direction to peel apart adhered strips. This force depends on the dimensions and thickness of the adhered strips and their yield stress, together with the fracture toughness of the bond. （剥离试验）两种材料之间的粘合强度，通过给定方向上剥离粘合条所需的力来测量。该力取决于粘合条的尺寸和厚度及其屈服应力，以及粘合剂的断裂韧性。 |
| Serrations | 锯齿 |
A row of notches or tooth-like projections on an edge or surface. On an engineering drawing, serrations on the surface of a circular component are shown over about 60° of arc. 边缘或表面上的一排凹口或齿状突起。在工程图纸上，圆形部件表面的锯齿超过约60°的圆弧。 |
| Collar | 圈、箍 |
A ring secured to, or integral with, a shaft to give axial location. 固定在轴上或与轴成一体以提供轴向位置的环。 |
| Kinetic friction | 动摩擦 |
(dynamic friction, sliding friction) (Unit N) The sliding resistance to relative motion of two surfaces in contact with each other. （动摩擦，滑动摩擦）（单位N）两个相互接触的表面相对运动的滑动阻力。 |
| Bearing strength | 承载强度 |
The maximum bearing stress that a material is capable of sustaining. 材料能够承受的最大承载应力。 |
| Clearance hole | 间隙孔 |
A hole of specified size such that a bolt, stud, etc. of the same nominal size will always pass through. 指定尺寸的孔，使相同标称尺寸的螺栓、螺柱等可以通过。 |
| Blowing | 吹气 |
The process by which a gas is transferred through a porous surface over which there is a gas flow. The effect is used to decrease skin friction and increase heat transfer, for example in turbine-blade cooling. 气体通过有气流的多孔表面转移的过程。该效应用于减少表面摩擦和增加传热，例如在涡轮叶片冷却的过程中。 |
| Fastener specification | 紧固件规格 |
A precise statement of set requirements to be satisfied by a fastener, its material, or its processing. It also indicates the procedure used to determine whether the requirements given are satisfied. 对紧固件、其材料或加工过程要满足的设定要求的精确陈述。它还指出了用于确定是否满足给定要求的程序。 |
| Turn-of-nut method | 螺母转动法 |
It applies preload by turning a nut through an angle that corresponds to a given elongation. 它通过将螺母旋转一个与给定伸长率相对应的角度来施加预载荷。 |
| Strain hardening | 应变硬化 |
An increase in hardness and strengthcaused by plastic deformation at temperatures below the recrystallization range. Also known as work hardening. (workhardening) The increase in stress above the initial yield stress required to deform a metal to greater strains in the plastic range at temperatures below the recrystallization range (cold working). Unloading after some strain or work input gives a harder and stronger material. 在低于再结晶范围的温度下，塑性变形导致硬度和强度的增加。也称为加工硬化。（加工硬化）在低于再结晶范围（冷加工）的温度下，使金属在塑性范围内变形至更大应变所需的高于初始屈服应力的应力增加。在一定的应变或功输入后卸载，会得到更硬、更强的材料。 |
| Oil-cooled | 油冷却 |
A term for a machine that uses circulating oil to remove heat. 使用循环油散热的机器的术语。 |
| 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。 |
| Rotary valve (rotating valve) | 旋转阀 |
A cylindrical or conical plug in which there is a transverse hole through which fluid can flow when the hole is aligned with the adjacent piping. 一种圆柱形或锥形塞，其中有一个横向孔，当该孔与相邻管道对齐时，流体可通过该孔流动。 |
| Screw compressor | 螺杆压缩机 |
A positive-displacement rotary compressor in which gas is progressively compressed by two intermeshing, counter-rotating, helical screws. 一种容积式旋转压缩机，其中气体由两个相互啮合、反向旋转的螺旋螺杆逐渐压缩。 |
| Thread form | 螺纹形式 |
The cross-sectional shape of the threads, defining thread angle, root, and crest profiles, etc. Thread length Length of that portion of the fastener which contains threads cut or rolled to full depth. 螺纹的横截面形状，定义螺纹角度、齿根和齿冠轮廓等。螺纹长度：紧固件中包含全深度切割或轧制螺纹的部分的长度。 |
| Mechanical energy (Unit J) | 机械能（单位J） |
The sum of kinetic energy and potential energy for an object or a mechanical system, including the energy stored in springs, etc. 物体或机械系统的动能和势能之和，包括储存在弹簧等中的能量。 |
| 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。 |
| Lathe | 车床 |
A machine tool in which work, gripped in the headstock, is rotated against the cutting tool to produce turned, bored, faced, or threaded components. 一种机床，其中夹持在主轴箱中的工件靠着切削工具旋转，以生产车削、钻孔、端面或螺纹部件。 |
| Crushing strain | 压应变 |
The supposed single strain that results in comminution of a brittle material. The corresponding stress is termed the crushing strength. Neither quantity can be a material constant as they must obey the laws of fracture mechanics and will depend on the type of testpiece, method of loading etc. 导致脆性材料粉碎的假定单应变。相应的应力称为抗压强度。这两个量都不能是材料常数，因为它们必须遵守断裂力学定律，并取决于试件类型、加载方法等。 |
| Water-jet cutting | 水射流切割 |
Cutting of materials such as rock by means of a high-speed jet of water containing abrasive particles. 通过含有磨料颗粒的高速水射流切割岩石等材料。 |
| Anode | 阳极 |
That electrode in a battery or corrosion cell which produces electrons. It is the electrode which is destroyed (corrodes). 电池或腐蚀电池中产生电子的电极。被破坏（腐蚀）的是电极。 |
| Caustic cracking | 苛性开裂 |
A form of stress-corrosion cracking most frequently encountered in carbon steels or iron-chromiumnickel alloys that are exposed to concentrated hydroxide solutions at temperatures of 200 to 250 °C (400 to 480 °F). Also known as caustic embrittlement. 在200至250°C（400至480°F）的温度下暴露于浓氢氧化物溶液中的碳钢或铁铬镍合金中最常遇到的一种应力腐蚀开裂形式。也称为碱脆。 |
| J-integral | J-积分 |
A mathematical expression describing a line or surface integral that encloses the crack front from one crack surface to the other, used to characterize the fracture toughness of a material having appreciable plasticity before fracture. The J-integral eliminates the need to describe the behavior of the material near the crack tip by considering the local stress-strain field around the crack front; JIc is the critical value of the J-integral required to initiate crack extension from a preexisting crack. 描述从一个裂纹表面到另一个裂纹正面的线或表面积分的数学表达式，用于表征断裂前具有可观塑性的材料的断裂韧性。J积分通过考虑裂纹前缘周围的局部应力应变场，无需描述裂纹尖端附近材料的行为；JIc是从先前存在的裂纹开始裂纹扩展所需的J积分的临界值。 |
| Guided-bend test | 导向弯曲试验 |
A test in which the specimen is bent to a definite shape by means of a punch (mandrel) and a bottom block. 用冲头（心轴）和底块将试样弯曲成一定形状的试验。 |
| Angström (Å) | 昂斯特罗姆（Å） |
An obsolete (non-SI) unit of length, sometimes still employed for atomic and crystallographic measurements. The conversion to SI is 1 Å = 10−10 m. 一种已被淘汰的（非SI）长度单位，有时仍用于原子和晶体学测量。转换为SI为1Å=10-10m。 |
| Shear | 扭剪 |
The type of force that causes or tends to cause two contiguous parts of the same body to slide relative to each other in a direction parallel to their plane of contact. 导致或倾向于导致同一物体的两个相邻部分在平行于其接触面的方向上相对滑动的力的类型。 |
| Fastener with waisted shank | 带腰柄的紧固件 |
Finished fastener with a shank diameter of ds < d2. 柄径ds |
| Absolute value error | 绝对值误差 |
The magnitude of the error dlsregarding the algebraic sign, or, for a vectorial error, disregarding its function. 关于代数符号的误差幅度，或者，对于矢量误差，不考虑其函数。 |
| Freezing range | 冻融范围 |
That temperature range between liquidus and solidus temperatures in which molten and solid constituents coexist. 熔融和固体成分共存的液相线和固相线温度之间的温度范围。 |
| Stress wave | 应力波 |
An unbalanced force, such as an impact, applied at one location in a body sets the material there into vibration that is transmitted to adjacent elements and ultimately to all parts of the body in the form of stress waves or wave packets. 施加在物体某个位置的不平衡力（如冲击力）会使物体中的材料产生振动，并以应力波或波包的形式传递到相邻元件，最终传递到物体的所有部位。 |
| 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。 |
| Profilometer | 轮廓仪 |
An instrument used to quantify the roughness of a surface. For a contact profilometer, a diamond stylus sweeps across the surface along a series of parallel lines. Noncontact profilometers use optical techniques to map the surface irregularities. 用于量化表面粗糙度的仪器。对于接触式轮廓仪，钻石触针沿一系列平行线扫过表面。非接触式轮廓仪使用光学技术绘制表面不规则。 |
| Thermochemical treatment | 热化学处理 |
Heat treatment carried out in a medium suitably chosen to produce a change in the chemical composition of the object by exchange with the medium. 在适当选择的介质中进行热处理，以通过与介质交换产生物体化学成分的变化。 |
| Olsen cup test | 奥尔森杯测试 |
A cupping test in which a piece of sheet metal, restrained except at the center, is deformed by a standard steel ball until fracture occurs. The height of the cup at time of fracture is a measure of the ductility. 一种杯突试验，其中一块金属板，除了中心以外，被一个标准钢球变形，直到发生断裂。断裂时杯的高度是延展性的量度。 |
| Maximum material condition | 最大材料条件 |
(maximum metal condition) The situation where the volume of a manufactured component corresponds to the upper limit for all toleranced external dimensions, and to the lower limit for all internal dimensions. （最大金属条件）制造部件的体积对应于所有公差外部尺寸的上限和所有内部尺寸的下限的情况。 |
| Galilean transformation | 伽利略变换 |
In steady fluid flow, the addition or subtraction of a constant velocity to the entire flowfield, e.g. so that flow can be considered relative to a moving object or flow feature, such as a shock wave. 在稳定的流体流动中，对整个流场增加或减少恒定速度，例如，可以考虑相对于移动物体或流动特征（例如冲击波）流动。 |
| 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。 |
| Flexural strength | 抗弯强度 |
The maximum stress in the outer fiber at the moment of crack or break. 断裂或断裂时刻外层纤维的最大应力。 |
| 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。 |
| A-basis | A-基础 |
Mechanical property value above which at least 99% of the population of values is expected to fall, with a confidence of 95%. Also called A-allowable. 机械性能值超过该值时，至少99%的值预计会下降，置信度为95%。也被称为A-容许。 |
| Compounding | 复合串联 |
In a steam engine (compound steam engine) or impulse turbine, the progressive reduction in pressure (expansion) across two or more stages in series. 在蒸汽机（复合蒸汽机）或脉冲涡轮机中，通过串联的两个或多个级逐渐降低压力（膨胀）。 |
| 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。 |
| Oxidizing flame | 氧化焰 |
A gas flame produced with excess oxygen in the inner flame. 在内部火焰中过量氧气产生的气体火焰。 |
| Stress cracking | 应力开裂 |
A family of failure modes, each of which involves high stress and chemical action. The family includes Hydrogen embrittlement, Stress corrosion cracking, stress embrittlement, and hydrogen-assisted stress corrosion. 一系列失效模式，每种模式都涉及高应力和化学作用。该系列包括氢脆、应力腐蚀开裂、应力脆化和氢辅助应力腐蚀。 |
| 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。 |
| Equilibrium diagram | 平衡图 |
A graphical representation of the temperature, pressure and composition limits of phase fields in an alloy system as they exist under conditions of complete equilibrium. In metal systems, pressure is usually considered constant. 在完全平衡条件下，合金系统中相场的温度、压力和成分极限的图形表示。在金属系统中，压力通常被认为是恒定的。 |
| Oxidative wear | 氧化磨损 |
A type of wear resulting from the sliding action between two metallic components that generates oxide films on the metal surfaces. These oxide films prevent the formation of a metallic bond between the sliding surfaces, resulting in fine wear debris and low wear rates. 由两个金属部件之间的滑动作用导致的一种磨损，在金属表面上产生氧化膜。这些氧化膜防止在滑动表面之间形成金属结合，导致细磨屑和低磨损率。 |
| Nut thickness | 螺母厚度 |
The nut thickness shall be the overall distance measured parallel to the axis of nut, from the top of the nut to the bearing surface, and shall include the thickness of the washer face where provided. 螺母厚度应为平行于螺母轴线测量的从螺母顶部到轴承表面的总距离，还应包括垫圈表面的厚度。 |
| Blade compressor | 叶片式压缩机 |
An oil-free, double-acting rotary compressor in which an angled blade attached to the inner surface of a rotating housing passes through a slot in a disk rotating about an axis perpendicular to that of the housing but offset from it. Air enters through apertures in the housing and leaves through a port in the housing. 一种无油双作用旋转式压缩机，其中连接到旋转外壳内表面的倾斜叶片穿过圆盘上的槽，该槽绕垂直于外壳的轴旋转，但偏离外壳。空气通过壳体中的孔进入，并通过壳体的端口离开。 |
| Strain-age embrittlement | 应变时效脆化 |
A loss in ductility accompanied by an increase in hardness and strength that occurs when low-carbon steel (especially rimmed or capped steel) is aged following plastic deformation. The degree of embrittlement is a function of aging time and temperature, occurring in a matter of minutes at about 200°C (400 °F), but requiring a few hours to a year at room temperature. 塑性变形后低碳钢（尤其是边缘钢或封顶钢）时效时发生的延展性损失，伴随着硬度和强度的增加。脆化程度是老化时间和温度的函数，在大约200°C（400°F）的温度下，在几分钟内发生，但在室温下需要几小时到一年。 |
| 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。 |
| 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）。 |
| Screw jack | 螺旋千斤顶 |
A lifting device (jack) consisting of a nut and square-threaded shaft at the top of which is a load-bearing pad. Rotation of the nut raises or lowers the pad. 一种起重装置（千斤顶），由螺母和方形螺纹轴组成，其顶部为承重垫。螺母的旋转可升高或降低衬垫。 |
| Eutectic carbide | 共晶碳化物 |
Carbide formed during freezing as one of the mutually insoluble phases participating in the eutectic reaction of ferrous alloys. 在冷冻过程中形成的碳化物，是参与铁合金共晶反应的互不溶相之一。 |
| Total combustion air (Unit kg/s) | 总燃烧空气（单位：kg/s） |
1. The combination of the stoichiometric flow of air required for combustion together with any excess air. 2. The flow of fresh air into a boiler plus any flue gas recirculated. 1.燃烧所需的化学计量空气流与任何过量空气的组合。2.进入锅炉的新鲜空气流加上再循环的任何烟气。 |
| Mechanical efficiency (η) | 机械效率（η） |
1. In general for a machine, the ratio of output work to input work. 2. For a compressor, the ratio of indicated power to shaft power; for a reciprocating engine or an expander, the ratio of shaft power to indicated power. 1.一般而言，机器的输出功与输入功之比。2.对于压缩机，指示功率与轴功率之比；对于往复式发动机或膨胀机，轴功率与指示功率之比。 |
| Crank pin | 曲柄销 |
It is a short shaft parallel to the axis of the crankshaft but radially offset from it, to which is attached the big end of a connecting rod in a bearing. Sometimes the crank pin is supported at one end only (a wrist pin) but in built-up or one-piece forged crankshafts, the crank pin is supported by thick plates (crank arms, crank webs) at either end. 它是一个短轴，平行于曲轴的轴线，但径向偏移，轴承中连杆的大端连接到该短轴上。有时曲柄销仅在一端支撑（腕销），在组合式或整体锻造曲轴中，曲柄销在两端由厚板（曲柄臂、曲柄腹板）支撑。 |
| 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。 |
| Effective discharge area (Unit m²) | 有效排放面积（单位m²） |
A nominal area for flow through a pressure relief valve used to determine the valve’s flow capacity given the pressure difference across it, the fluid density and correction factors to allow for compressibility, the back pressure and the coefficient of discharge. 流经泄压阀的标称面积，用于确定阀门的流量，给定压力差、流体密度和允许可压缩性的校正因子、背压和排放系数。 |
| Stainless steels | 不锈钢 |
Iron-base alloys that are highly resistant to corrosion in many environments. The predominant alloying element is chromium, which, like iron at room temperature, has BCC crystal structure. Corrosion resistance by passivation is achieved by the formation of chromium oxide on the steel surface. Nickel, which has FCC crystal structure, is another important addition for some steels. Other additions used to enhance properties include manganese, molybdenum, niobium, and titanium. There are several classes of stainless steel. 在许多环境中具有高度耐腐蚀性的铁基合金。主要的合金元素是铬，与室温下的铁一样，铬具有BCC晶体结构。钝化抗腐蚀性是通过在钢表面形成氧化铬来实现的。具有FCC晶体结构的镍是某些钢的另一种重要添加剂。其他用于增强性能的添加剂包括锰、钼、铌和钛。不锈钢的种类有好几种。 |
| 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。 |
| Coarse threads | 粗螺纹 |
Threads with relatively large separation between corresponding points on the threads. 螺纹上相应点之间的间距相对较大的螺纹。 |
| Yielding | 屈服 |
Evidence of plastic deformation in structural materials. Also known as plastic flow or creep. 结构材料塑性变形的证据。也称为塑性流动或蠕变。 |
| Full annealing | 全退火 |
An imprecise term that denotes an annealing cycle to produce minimum strength and hardness. For the term to be meaningful, the composition and starting condition of the material and the time-temperature cycle used must be stated. Annealing a ferrous alloy by austenitizing and then cooling slowly through the transformation range. 一个不精确的术语，表示产生最小强度和硬度的退火循环。为了使该术语有意义，必须说明材料的组成和起始条件以及使用的时间-温度循环。通过奥氏体化退火铁合金，然后在转变范围内缓慢冷却。 |
| Push rod | 推杆 |
A rod which opens and closes a valve via a valve rocker in an overhead-valve piston engine. The rod is actuated by a camshaft located in the crankcase. 在顶置气门活塞发动机中，通过气门摇臂打开和关闭气门的杆。连杆由曲轴箱中的凸轮轴驱动。 |
| Normality | 常态 |
The principle that the vector sum of plastic strain increments is perpendicular to the yield surface. 塑性应变增量矢量和垂直于屈服面的原理。 |
| Newton’s law of gravitation | 牛顿万有引力定律 |
(Newton’s law of universal gravitation) Any two bodies exert a gravitational force of attraction F on each other directed along the line joining their centres of mass, in magnitude proportional to the product of their masses and inversely proportional to the square of the distance r between them. （牛顿万有引力定律）任何两个物体沿其质心连接线相互施加引力F，其大小与其质量乘积成正比，与它们之间距离r的平方成反比。 |
| Cavitation tunnel | 空泡试验筒 |
A closed-circuit recirculating water tunnel in which the static pressure can be reduced to sufficiently low levels for cavitation studies to be performed. 一种闭路循环水隧洞，其中静压可降至足够低的水平，以便进行气蚀研究。 |
| Dimensioning | 尺寸标注 |
The specification on an engineering drawing of the size (e.g. length, radius, angle, or spacing) and the relative location (e.g. angular position) of each feature of a component. The numerical values often include the tolerances. There should be no more dimensions than are necessary to manufacture the component. 工程图纸上对部件每个特征的尺寸（例如长度、半径、角度或间距）和相对位置（例如角位置）的规范。数值通常包括公差。尺寸不应超过制造组件所需的尺寸。 |
| Knot (kn) | 节（kn） |
A non-SI unit defined as one nautical mile per hour. The conversion to SI is 1 kn = 5.144 444 444×10−1 m/s. 非国际单位制单位，定义为每小时一海里。转换为SI为1kN=5.144444×10−1米/秒。 |
| Temper | 回火 |
(1) In heat treatment, reheating hardened steel or hardened cast iron to some temperature below the eutectoid temperature for the purpose of decreasing hardness and increasing toughness. The process also is sometimes applied to normalized steel. (2) In tool steels, temper is sometimes used, but inadvisedly, to denote the carbon content. (3) In nonferrous alloys and in some ferrous alloys (steels that cannot be hardened by heat treatment), the hardness and strength produced by mechanical or thermal treatment, or both, and characterized by a certain structure, mechanical properties, or reduction in area during cold working. （1）在热处理中，将硬化钢或硬化铸铁重新加热到共析温度以下的温度，以降低硬度和增加韧性。该工艺有时也适用于正火钢。（2）在工具钢中，有时使用回火来表示碳含量，但这是不恰当的。（3）在非铁合金和一些铁合金（不能通过热处理硬化的钢）中，通过机械或热处理或两者产生的硬度和强度，其特征是在冷加工过程中具有一定的结构、机械性能或面积减小。 |
| British Standards Institution (BSI) | 英国标准协会（BSI） |
The Institution in the UK responsible for the preparation and publication of standard specifications (British standards) for manufactured goods, their design, manufacture and testing. 负责为制成品及其设计、制造和测试制定和发布标准规范（英国标准）的英国机构。 |
| Gamma iron | 加马铁 |
The face-centered cubic form of pure iron, stable from 910 to 1400 °C (1670 to 2550 °F). 纯铁的面心立方形式，在910至1400°C（1670 2550°F）温度范围内稳定。 |
| Counter sink | 台面水槽 |
To cut or shape a depression in an object so that the head of a screw may set flush or below the surface. 在物体上切割或塑造一个凹陷，使螺钉的头部可以齐平或低于表面。 |
| Critical cooling rate | 临界冷却速度 |
The rate of continuous cooling required to prevent undesirable transformation. For steel, it is the minimum rate at which austenite must be continuously cooled to suppress transformations above the Ms temperature. 防止不期望的转变所需的连续冷却速率。对于钢，它是奥氏体必须持续冷却以抑制Ms温度以上的转变的最小速率。 |
| 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。 |
| Diaphragm meter | 隔膜计 |
A dry flow meter in which there are two or more interconnected chambers, each having a diaphragm in the wall. The chambers empty and fill alternately and the flow rate of gas is determined from the movement of diaphragms. Diaphragm meters are commonly used to monitor domestic and commercial gas supply. 一种干式流量计，其中有两个或多个相互连接的腔室，每个腔室的壁上都有一个隔膜。腔室交替排空和填充，气体流速由隔膜的移动确定。隔膜流量计通常用于监测家用和商用燃气供应。 |
| Joint space | 关节空间 |
The description of the position and orientation of a robot in terms of the rotational angles and translational positions of the joints. Kinematic analysis, normally using homogeneous transforms, allows conversion between this description and the end‐effector position and orientation in x,y,z space. 根据关节的旋转角度和平移位置描述机器人的位置和方向。通常使用齐次变换的运动学分析允许在该描述与x、y、z空间中的末端执行器位置和方向之间进行转换。 |
| Working fluid | 工作流体 |
In thermodynamics, the fluid contained within the boundary of a system that experiences changes in its properties during any fluid dynamic or thermodynamic process. 在热力学中，包含在系统边界内的流体，在任何流体动力学或热力学过程中其性质发生变化。 |
| Zone melting (zone refining) | 区域熔炼（区域精炼） |
A process of purification of materials in which a narrow molten zone is moved along the length of the material, resulting in impurities being segregated at one end. 一种净化材料的过程，其中一个狭窄的熔融区沿材料长度移动，导致杂质在一端分离。 |
| Wrought iron | 锻铁 |
A highly ductile (but anisotropic) type of iron containing elongated slag fibres that resulted from the method of manufacture in which excess carbon in pig iron was burnt and worked out. The yield strength is some 200 MPa, tensile strength 320 MPa, and reduction of area on a 50-mm gauge length up to 35%. Now replaced by steel. 一种高韧性（但各向异性）的铁，含有细长的矿渣纤维，由生铁中多余的碳燃烧和加工的制造方法产生。屈服强度约为200MPa，抗拉强度为320MPa，50mm标距上的面积缩减率高达35%。现在被钢所取代。 |
| Assembly line | 流水线 |
A system of mass production in which work is moved progressively from one operation to another, ultimately to give the final complete product. 一种大规模生产系统，其中工作逐渐从一个操作转移到另一个操作，最终得到完整产品。 |
| Tare weight (Unit N) | 皮重（单位N） |
The weight of an empty container. 空容器的重量。 |
| Stretch-bending test | 拉伸弯曲试验 |
A simulative test for sheet metal formability in which a strip of sheet metal is clamped at its ends in lock beads and deformed in the center by a punch. Test conditions are chosen so that fracture occurs in the region of punch contact. 金属板成形性的模拟试验，其中金属板条在其端部夹紧在锁珠中，并通过冲头在中心变形。选择试验条件，以便在冲头接触区域发生断裂。 |
| Ultrasonic extensometer | 超声波伸长计 |
An electronic instrument which measures the change in length of a fastener ultrasonically as, or before and after, the fastener is tightened. 一种电子仪器，可在紧固件拧紧时或前后通过超声波测量紧固件长度的变化。 |
| Recrystallization temperature | 再结晶温度 |
The approximate minimum temperature at which complete recrystallization of a cold-worked metal occurs within a specified time. 冷加工金属在规定时间内发生完全再结晶的近似最低温度。 |
| Full-size fastener | 全尺寸紧固件 |
Finished fastener with a shank diameter of ds ≈ d or ds > d, or screw threaded to the head, or fully threaded stud. 柄径为ds≈d或ds>d的紧固件，或螺纹连接到头部，或全螺纹螺柱。 |
| Ferrite | 铁素体 |
A solid solution of one or more elements in body-centered cubic iron. Unless otherwise designated (for instance, as chromium ferrite), the solute is generally assumed to be carbon. On some equilibrium diagrams, there are two ferrite regions separated by an austenite area. The lower area is alpha ferrite; the upper, delta ferrite. If there is no designation, alpha ferrite is assumed. 一种或多种元素在体心立方铁中的固溶体。除非另有说明（例如，铁酸铬），否则通常假定溶质为碳。在一些平衡图上，有两个铁素体区域被一个奥氏体区域隔开。下部区域为α铁素体；上部，δ铁氧体。如果没有指定，则假定为 α 铁氧体。 |
| Surface tension (σ, γ) (Unit N/m) | 表面张力（σ，γ）（单位：N/m） |
At the interface between a liquid and a gas or two immiscible liquids, unbalanced cohesive forces acting on the liquid molecules at the interface lead to the property surface tension which causes tensile forces to develop as if it were a skin or membrane. 液体和气体或两种不混溶液体之间的界面处，作用在界面处的液体分子上的不平衡内聚力导致表面张力的性质，从而导致张力的发展，就像皮肤或薄膜一样。 |
| Plug | 螺塞 |
1. An object, usually tapered, used to block a hole to prevent fluid from escaping or flowing. 2. The central moveable part of a valve. 3. In the flow of a yield-stress fluid through a pipe or duct, the central region is often assumed to take the form of a plug with uniform axial velocity. 4. In thermoforming, a shaping tool that forces a heated plastic sheet into a female mould. 1.一种物体，通常为锥形，用于堵塞孔以防止流体逸出或流动。2.阀门的中心可移动部分。3.在屈服应力流体通过管道或管道的流动中，中心区域通常假定为具有均匀轴向速度的塞子形式。4.在热成型技术中，一种成型工具，将加热的塑料板压入阴模中。 |
| Brake fluid | 制动液 |
The hydraulic fluid used to transmit force to the pistons in disc brakes or the wheel cylinders in drum brakes. Requirements include a high boiling point and low hygroscopy. 用于将力传递到盘式制动器中的活塞或鼓式制动器中的轮缸的液压油。要求包括高沸点和低吸湿性。 |
| 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。 |
| Twist | 扭转 |
The helix produced in a cylindrical component, such as a shaft, wire, tensioned cable, or rope, when one end is rotated relative to the other. Measured either as the number of turns per unit length, or by the helix angle (twist angle). 当一端相对于另一端旋转时，在圆柱形部件（如轴、钢丝、张紧电缆或绳索）中产生的螺旋。以每单位长度的圈数或螺旋角（扭曲角）测量。 |
| Initial stress | 初始应力 |
The stress produced by strain in a specimen immediately on achieving the given constant-strain conditions in a stress-relaxation test before stress-relaxation occurs. Sometimes referred to as instantaneous stress. 在应力松弛发生之前，在应力松弛试验中达到给定的恒定应变条件时，试样立即应变所产生的应力。有时称为瞬时压力。 |
| Avogadro constant | 阿伏伽德罗常数 |
(Avogadro number, NA) A fundamental physical constant with the fixed numerical value 6.022 140 76 × 1023 mol−1. The mole contains exactly this number of elementary entities. A minor adjustment to the value of the Avogadro constant was made effective on 20 May 2019. （阿伏伽德罗数，NA）一个固定数值为6.02214076×1023mol的基本物理常数−摩尔正好包含这个数量的基本实体。对阿伏伽德罗常数值的微小调整于2019年5月20日生效。 |
| Blind rivet | 盲孔铆钉 |
A rivet that enables a connexion to be made from one side only of an assembly. 一种铆钉，可以仅从组件的一侧进行连接。 |
| Atom | 原子 |
The smallest unit of matter that has the properties of a chemical element. The simplest description of an atom (Bohr model) is of a compact nucleus surrounded by one or more orbiting electrons. 具有化学元素性质的最小物质单位。原子的最简单描述（玻尔模型）是由一个或多个轨道电子包围的致密原子核。 |
| Effective length of a bolt | 螺栓的有效长度 |
The grip length plus some portion of the bolt (often one-half of the thickness of the nuts) which lies within the nut(s) plus some portion (often one-half the thickness) of the head. 握持长度加上位于螺母内的螺栓的某些部分（通常是螺母厚度的二分之一）加上头部的某些部分（通常是厚度的二分之一）。 |
| Track rod | 横拉杆 |
A bar connecting the ends of the steering arms in an automotive vehicle. 连接汽车转向臂端部的杆。 |
| Linear-elastic fracture mechanics | 线弹性断裂力学 |
A method of fracture analysis that can determine the stress (or load) required to induce fracture instability in a structure containing a cracklike flaw of known size and shape. 一种断裂分析方法，可确定在含有已知尺寸和形状裂纹状缺陷的结构中引起断裂不稳定性所需的应力（或载荷）。 |
| Breaks | 断裂 |
Creases or ridges usually in “untempered” or in aged material where the yield point has been exceeded. Depending on the origin of the break, it may be termed a cross break, a coil break, an edge break, or a sticker break. 通常在“未回火”或超过屈服点的老化材料中出现折痕或隆起。根据断裂的起源，它可能被称为交叉断裂、线圈断裂、边缘断裂或贴纸断裂。 |
| Acoustic emission | 声发射 |
(stress-wave emission) Sound emitted by some materials when deformed under load. It arises from stress waves emitted by sudden dislocation motion in crystals, slip, crack growth, etc. （应力波发射）某些材料在负载下变形时发出的声音。它是由晶体中突然的位错运动、滑移、裂纹扩展等发出的应力波引起的。 |
| Sound pressure (Unit μPa) | 声压（单位：μPa） |
The instantaneous deviation of pressure from the ambient pressure caused by the passage of a sound wave, which can be measured by a microphone in air and a hydrophone in water. 声波传播引起的压力与环境压力的瞬时偏差，可通过空气中的麦克风和水中的水听器测量。 |
| Effective crack size (ae) | 有效裂纹尺寸（ae） |
The physical crack size augmented for the effects of cracking plastic deformation. Sometimes the effective crack size is calculated from a measured value of a physical crack size plus a calculated value of a plastic-zone adjustment. A preferred method for calculation of effective crack size compares compliance from the secant of a load-deflection trace with the elastic compliance from a calibration for the type of specimen. 由于裂纹塑性变形的影响，物理裂纹尺寸增大。有时，根据物理裂纹尺寸的测量值加上塑性区调整的计算值来计算有效裂纹尺寸。计算有效裂纹尺寸的首选方法是将载荷-挠度轨迹正割的柔度与试样类型校准的弹性柔度进行比较。 |
| Transition temperature (Unit K) | 转变温度（单位K） |
(1) An arbitrarily defined temperature that lies within the temperature range in which metal fracture characteristics (as usually determined by tests of notched specimens) change rapidly, such as from primarily fibrous (shear)to primarily crystalline (cleavage) fracture. (2) Sometimes used to denote an arbitrarily defined temperature within a range in which the ductility changes rapidly with temperature. (transition point) 1. The temperature at which the mechanism of fracture in metal alloys having a face-centred cubic crystal structure changes from ductile void growth to brittle cleavage. 2. The temperature at which a material changes from one crystal state to another. （1） 任意定义的温度，位于金属断裂特性（通常通过缺口试样的试验确定）快速变化的温度范围内，如从主要纤维（剪切）断裂到主要结晶（解理）断裂。（2） 有时用于表示延性随温度快速变化的范围内的任意定义的温度。（转变点）1.具有面心立方晶体结构的金属合金的断裂机制从韧性孔洞生长转变为脆性解理的温度。2.材料从一种晶体状态转变为另一种晶体的温度。 |
| High-tensile bolt | 高强度螺栓 |
(high-tension bolt) A bolt manufactured from an alloy steel that has a high tensile strength of about 1 GPa. （高压螺栓）由合金钢制成的螺栓，具有约1GPa的高抗拉强度。 |
| Conduit | 导管 |
A hollow object, of metal, plastic, glass, ceramic, etc., which is relatively long compared with its lateral dimensions and through which there is fluid flow. 由金属、塑料、玻璃、陶瓷等制成的中空物体，与其横向尺寸相比相对较长，并且有流体流过。 |
| Pascal (Pa) | 帕斯卡（Pa） |
The SI unit of pressure, 1 Pa = 1 N/m². 压力的国际单位制，1Pa=1N/m²。 |
| Clearance angle | 后角 |
(relief angle) (Unit °) The angle between the underneath or flank of a cutting tool and the machined surface. （后角）（单位°）切削刀具的底部或侧面与加工表面之间的角度。 |
| Nominal stress | 名义应力 |
The stress at a point calculated on the net cross section by simple elasticity theory without taking into account the effect on the stress produced by stress raisers such as holes, grooves, fillets, etc. 通过简单弹性理论在净截面上计算的点处的应力，不考虑孔、槽、圆角等应力提升器产生的应力影响。 |
| Compression pressure (Unit Pa) | 压缩压力（单位Pa） |
The pressure produced in a cylinder of a piston engine by compression of air in the absence of fuel. 在没有燃料的情况下通过压缩空气在活塞发动机的气缸中产生的压力。 |
| Waste-heat recovery | 废热回收 |
The recovery of thermal energy from flue and exhaust gases, or from liquids heated in industrial processes. Recovery devices include pre-heaters, recuperators, regenerators, and waste-heat boilers. 从烟道和废气中或从工业过程中加热的液体中回收热能。回收装置包括预热器、回热器、再生器和余热锅炉。 |
| Tensiometer | 张力计 |
An instrument used to measure surface tension. 用来测量表面张力的仪器。 |
| 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。 |
| Edge distance | 边距 |
The distance from the edge of a bearing specimen to the center of the hole in the direction of applied force. 在作用力方向上，从轴承试样的边缘到孔中心的距离。 |
| Bias pressure (Unit Pa) | 偏压（单位Pa） |
In a fluidic device controlled by pressure difference, the magnitude of that difference. 在由压力差控制的流体装置中，该差值的大小。 |
| Selective quenching | 局部淬火 |
Quenching only certain portions of an object. 仅淬火工件的某些部分。 |
| Friction loss (Unit J) | 摩擦损失（单位J） |
The conversion of mechanical energy to heat due to friction within a machine, mechanism, linkage, etc. 由于机器、机构、连杆等内部的摩擦而将机械能转化为热能。 |
| Double aging | 双级时效 |
Employment of two different aging treatments to control the type of precipitate formed from a supersaturated matrix in order to obtain the desired properties. The first aging treatment, sometimes referred to as intermediate or stabilizing, is usually carried out at higher temperature than the second. 采用两种不同的时效处理来控制由过饱和基质形成的沉淀物类型，以获得所需的性能。第一次时效处理，有时称为中间处理或稳定处理，通常在比第二次更高的温度下进行。 |
| Gas compressor | 气体压缩机 |
A machine which draws in a gas at low pressure and delivers it at high pressure, usually accompanied by a temperature increase. Compressor designs include axial, centrifugal, diaphragm, reciprocating, and rotary (including the blade compressor). 一种在低压下吸入气体并在高压下输送气体的机器，通常伴随着温度升高。压缩机设计包括轴流式、离心式、隔膜式、往复式和旋转式（包括叶片式压缩机）。 |
| 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。 |
| 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。 |
| 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。 |
| Thermoelectric junction | 热电结 |
A welded, soldered, or twisted connection between the ends of two wires of dissimilar metals, as in a thermocouple. 两根不同金属线的末端之间的焊接、锡焊或绞合连接，如热电偶。 |
| Design heating load (Unit kW) | 设计热负荷（单位kW） |
The heating requirements based on a specified number of heating degree days, or required to maintain a building or other enclosed space at a specified temperature for a given outside temperature. 基于指定的采暖度日数的加热要求，或在给定的外部温度下将建筑物或其他封闭空间保持在指定温度下所需的加热要求。 |
| 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。 |
| 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。 |
| Metallurgy | 冶金 |
The study of the atomic, crystallographic, microstructural, mechanical, and physical properties of metallic elements and alloys and their applications. 研究金属元素和合金的原子、晶体学、微观结构、机械和物理特性及其应用。 |
| Precipitation hardening | 沉淀硬化 |
Hardening caused by the precipitation of a constituent from a supersaturated solid solution. 因成分从过饱和固溶体沉淀而导致的硬化。 |
| Micrometer | 千分尺 |
(micrometer gauge) A mechanical-contact device for the accurate measurement of the length, width, diameter, etc. of an object, the depth of a hole, the height of a step, etc. The usual arrangement is a spindle that is moved by rotation of a thimble, the distance then being read off a vernier scale. （千分尺）一种机械接触装置，用于精确测量物体的长度、宽度、直径等、孔的深度、台阶的高度等。通常的布置是通过顶针的旋转移动主轴，然后通过游标尺读取距离。 |
| Concurrent engineering | 并行工程 |
The integration of the procedures for product design, material selection and manufacturing method to include life-cycle analysis. 产品设计、材料选择和制造方法程序的整合，包括生命周期分析。 |
| Plane-stress fracture toughness (Kc) | 平面应力断裂韧性（Kc） |
In linear-elastic fracture mechanics, the value of the crack-extension resistance at the instability condition determined from the tangency between the R-curve and the critical crack-extension force curve of the specimen. 在线弹性断裂力学中，由试样的R曲线和临界裂纹扩展力曲线之间的切线确定的不稳定条件下裂纹扩展阻力的值。 |
| 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。 |
| Induction hardening | 感应淬火 |
A surface-hardening process in which only the surface layer of a suitable ferrous workpiece is heated by electromagnetic induction to above the upper critical temperature and immediately quenched. 一种表面硬化工艺，在该工艺中，只有合适的含铁工件的表面层通过电磁感应加热到高于上临界温度，并立即淬火。 |
| Deposit gauge | 沉积量计 |
(deposition gauge) An instrument employed in air pollution studies for measuring the amount of pollutant deposited on a given area in a given time under given conditions. （沉降计）在空气污染研究中使用的仪器，用于测量在给定条件下在给定时间内沉积在给定区域上的污染物量。 |
| 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。 |
| Torque converter | 变矩器 |
A turbomachine used for torque amplification consisting of an impeller, a turbine, and a reaction member. Applications include motor-vehicle transmissions. 用于扭矩放大的涡轮机，由叶轮、涡轮机和反作用构件组成。应用包括机动车变速器。 |
| 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。 |
| Single-shear test | 单剪试验 |
(1) A shear test similar to the double-shear test used for round-bar specimens, but that uses only one stationary shear blade. (2) A shear test that uses a sheet or thin-plate specimen. （1）一种剪切试验，类似于用于圆棒试样的双剪切试验，但仅使用一个固定剪切刀片。（2）使用薄板或薄板试样的剪切试验。 |
| Selective heating | 局部加热 |
Intentionally heating only certain portions of a workpiece. 有意仅加热工件的某些部分。 |
| 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。 |
| 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。 |
| 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。 |
| Steady pin | 定位销 |
A dowel, key, or pin that prevents a pulley from turning on its shaft. 防止滑轮在其轴上转动的销钉、键或销。 |
| Tribology | 摩擦学 |
The science and technology concerned with interacting surfaces in relative motion. 与相对运动中相互作用的表面有关的科学和技术。 |
| Displacement | 移位 |
The distance that a chosen measurement point on a cracked specimen displaces normal to the crack plane as the crack grows. 随着裂纹扩展，裂纹试样上选定的测量点垂直于裂纹平面位移的距离。 |
| 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。 |
| Load | 负载 |
For testing machines, a force applied to a test piece that is measured in units such as pound-force, newton, or kilogram-force. 对于试验机，施加在试件上的力，以磅力、牛顿或千克力等单位测量。 |
| Spring constant | 弹簧常数 |
The ratio between the forces exerted on a spring (or a bolt) and the deflection thereof. Has the dimensions of force per unit change in length (e.g., lb=in.). Also called Stiffness. 施加在弹簧（或螺栓）上的力与其挠度之间的比率。具有每单位长度变化的力的尺寸（例如lb=in.）。也称为刚度。 |
| Square thread | 方螺纹 |
A form of screw thread in which the cross–section of the thread forms a square, making the width of the thread equal to the space between the threads. 螺纹的一种形式，螺纹的横截面形成正方形，使螺纹的宽度等于螺纹之间的间距。 |
| Solenoid | 螺线管 |
A coil of electrically-conducting wire wrapped around a metal core, typically iron, to produce a magnetic field and hence a force on the core when an electric current passes through the coil. Solenoids are widely used to produce linear movement to actuate valves (solenoid valves) and other devices. 绕在金属芯（通常为铁）上的导线线圈，当电流通过线圈时产生磁场，从而在芯上产生力。电磁阀广泛用于产生线性运动以驱动阀（电磁阀）和其他装置。 |
| Bright annealing | 光亮退火 |
Annealing in a protective medium to prevent discoloration of the bright surface. 在保护介质中退火以防止光亮表面变色。 |
| Brayton cycle | 布雷顿循环 |
(Joule cycle) An air standard cycle that is the ideal cycle for a gasturbine engine. As shown on the diagram of pressure (p) ʋs specific volume (ʋ), it consists of four internally reversible processes: isentropic compression in a compressor (1–2), isobaric heat addition in a combustor (2–3), isentropic expansion in a turbine (3–4) and isobaric heat rejection. The cycle can be extended to include regeneration, reheating, and intercooling. （焦耳循环）一种空气标准循环，是燃气轮机发动机的理想循环。循环可以扩展到包括再生、再热和中冷。 |
| 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。 |
| Crank angle (Unit °) | 曲柄角度（单位°） |
The angle between the crank of a slider-crank mechanism and a line from the crankshaft centreline to the piston axis. 曲柄滑块机构的曲柄与曲轴中心线到活塞轴线的直线之间的角度。 |
| Fretting fatigue | 微动疲劳 |
Fatigue fracture that initiate at a surface area where fretting has occurred. The progressive damage to a solid surface that arises from fretting. 在发生微动的表面区域开始的疲劳断裂。由微动引起的对固体表面的渐进性损坏。 |
| Valve plug | 阀塞 |
A conical or cylindrical plug, in which there are transverse holes, in a valve, such as a plug valve. Flow through the holes occurs when the plug is rotated. 阀门中的圆锥形或圆柱形阀塞，其中有横向孔，如旋塞阀。旋转阀塞时，会发生通过孔的流动 |
| Hypoeutectic alloy | 亚共晶合金 |
In an alloy system exhibiting a eutectic, any alloy whose composition has an excess of base metal compared with the eutectic composition, and whose equilibrium microstructure contains some eutectic structure. 在呈现共晶的合金系统中，其成分比共晶成分多的任何合金，其平衡微观结构包含一些共晶结构。 |
| Amplifier | 放大器 |
A device by which the output of a hydraulic, pneumatic, or electrical source is increased. 增加液压、气动或电源输出的装置。 |
| Coil spring | 螺旋弹簧 |
A spiral (‘clockwork’) or helical (cylindrical) spring. A spring steel wire wound in a spiral pattern. 螺旋（“发条”）或螺旋（圆柱形）弹簧。以螺旋状缠绕的弹簧钢丝。 |
| Compression test | 压缩测试 |
A method for assessing the ability of a material to withstand compressive loads. The determination of the stress–strain curve of a material by axial loading of a specimen in compression. In brittle materials failure is in the elastic range; more ductile materials will yield before fracture; very ductile materials will plastically deform extensively before failure. The compression strength (compressive strength), with unit Pa, is the compressive stress that causes failure in a component or structure. 一种评估材料承受压缩载荷能力的方法。通过压缩试样的轴向载荷确定材料的应力-应变曲线。在脆性材料中，破坏在弹性范围内；韧性更强的材料在断裂前会屈服；韧性很强的材料在失效前会发生广泛的塑性变形。抗压强度（抗压强度），单位为Pa，是导致部件或结构失效的压应力。 |
| Condenser vacuum | 冷凝器真空 |
The sub-atmospheric pressure imposed on the condenser of a steam-power plant which leads to an appreciable increase in overall efficiency. 施加在蒸汽发电厂冷凝器上的低于大气压的压力导致整体效率显着提高。 |
| 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。 |
| Indentation hardness | 压痕硬度 |
The resistance of a material to indentation as determined by hardness testing. The indenter, which may be spherical or diamond shaped, is pressed into the surface of a metal under specified load for a given time. (Unit Pa or, non-SI, kgf/mm²) A measurement of hardness taken by means of an indenter, pressed into a material by a load, which makes a permanent impression. The hardness is given by the load divided by the projected (sometimes surface) area of the indentation. Plasticity theory shows that the hardness is about 2.5–3 times the uniaxial yield stress. 通过硬度测试确定的材料抗压痕的能力。压头可以是球形或菱形，在规定的载荷下压入金属表面一段时间。（单位Pa或，非国际单位制，kgf/mm²）通过压头测量硬度，压入材料，形成永久压痕。硬度由载荷除以压痕的投影（有时是表面）面积得出。塑性理论表明，硬度约为单轴屈服应力的2.5–3倍。 |
| Alternating stress | 交替应力 |
(Unit Pa) Originally, stresses of changing sign (tension-tocompression-to-tension, etc.) in a component produced by alternating forces acting in opposite directions, but now generally used to describe stresses that vary but may keep the same sign, as produced by periodic, out-of–balance, or vibrational loads. （单位Pa）最初，构件中由相反方向的交变力产生的符号变化的应力（张力到压缩到张力等），但现在通常用于描述变化但可能保持相同符号的应力，如由周期性、失衡或振动载荷产生的应力。 |
| Planar anisotropy | 平面异向性 |
A variation in physical and/or mechanical properties with respect to direction within the plane of material in sheet form. 在片状材料平面内，物理和/或机械性能相对于方向的变化。 |
| Materials science | 材料科学 |
The study of the properties, behaviour, and application of solid substances such as metals, ceramics, glasses, polymers, composites, biomaterials, and semiconductors, at all scales from the atomic to the macroscopic. The topic has its origins in metallurgy. 研究金属、陶瓷、玻璃、聚合物、复合材料、生物材料和半导体等固体物质的特性、行为和应用，涵盖从原子到宏观的所有范围。起源于冶金学。 |
| Differential heating | 差动加热 |
Heating that intentionally produces a temperature gradient within an object such that, after cooling, a desired stress distribution or variation in properties is present within the object. 加热有意在物体内产生温度梯度，从而在冷却后，在物体内出现所需的应力分布或特性变化。 |
| Overheating | 过热 |
Heating a metal or alloy to such a high temperature that its properties are impaired. When the original properties cannot be restored by further heat treating, by mechanical working, or by a combination of working and heat treating, the overheating is known as burning. 将金属或合金加热至其性能受损的高温。当通过进一步热处理、机械加工或加工与热处理的组合无法恢复原始性能时，过热称为燃烧。 |
| Vickers hardness test | 维氏硬度测试 |
An indentation hardness test employing a 136° diamond pyramid indenter (Vickers) and variable loads, enabling the use of one hardness scale for all ranges of hardness—from very soft lead to tungsten carbide. Also know as diamond pyramid hardness test. 采用136°金刚石棱锥压头（维氏硬度计）和可变载荷的压痕硬度测试，能够对从极软铅到碳化钨的所有硬度范围使用一个硬度标度。也称为钻石金字塔硬度测试。 |
| Vapour static pressure | 蒸汽静压 |
(Unit Pa or bar) A pressure analogous to hydrostatic pressure, where the fluid is a vapour such as steam. A term used in geothermal applications. （单位Pa或bar）类似于静水压力的压力，其中流体是蒸汽，如蒸汽。地热应用中使用的术语。 |
| 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。 |
| Coarsening | 粗粒化 |
An increase in the grain size, usually, but not necessarily, by grain growth. 晶粒尺寸的增加，通常但不一定是晶粒变大。 |
| Critical temperature ranges | 临界温度范围 |
Synonymous with transformation ranges, which is the preferred term. 与转换范围同义，这是首选术语。 |
| 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。 |
| Shoulder bolt | 轴肩螺栓 |
A bolt for which the unthreaded cylindrical section between the thread and the head is of larger diameter than the threaded section, precisely machined to length and diameter and hardened 一种螺栓，其螺纹和头部之间的无螺纹圆柱段的直径大于螺纹段的直径，精确加工至长度和直径并硬化 |
| Starting valve (regulator) | 起动阀（调节器） |
A valve which admits steam from the boiler to the cylinder(s) of a steam engine. 将蒸汽从锅炉送入蒸汽机汽缸的阀门。 |
| 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）。 |
| 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。 |
| Sigma-phase embrittlement | σ相脆化 |
Embrittlement of iron-chromium alloys (most notably austenitic stainless steels) caused by precipitation at grain boundaries of the hard, brittle intermetallic sigma phase during long periods of exposure to temperatures between approximately 565 and 980 °C (1050 and 1800 °F). Sigmaphase embrittlement results in severe loss in toughness and ductility and can make the embrittled material structure susceptible to intergranular corrosion. 铁铬合金（最显著的是奥氏体不锈钢）的脆化是由于在长时间暴露于约565至980°C（1050至1800°F）的温度下，硬脆金属间化合物σ相的晶界处沉淀造成的。σ相脆化导致韧性和延展性的严重损失，可使脆化的材料结构易于发生晶间腐蚀。 |
| Centrifugal | 离心式 |
Acting or moving in a direction away from the axis of rotation of a rotating body. 沿远离旋转体的旋转轴的方向作用或移动。 |
| Double-shear test | 双剪试验 |
A shear test having two stationary, shear blades and one moving one and that uses solid round bars as test specimens. 一种剪切试验，具有两个固定的剪切刀片和一个移动的刀片，并使用实心圆棒作为试样。 |
| Concentration ratio | 浓度比 |
For a concentrating solar collector, the ratio of the projected area of the concentrator facing the solar beam to the actual area of the receiver. 对于聚光太阳能集热器，集中器面向太阳光束的投影面积与接收器的实际面积之比。 |
| Rpm (N) | 转速（N） |
An abbreviation for revolutions per minute. It is a widely used non-SI unit for rotational speed. The corresponding angular velocity ω in rad/s is given by πN/30. Rps (revolutions per second) is also used, the angular velocity then being 2πN. 每分钟转数的缩写。它是一种广泛使用的转速非SI单位。相应的角速度ω，单位为rad/s，由πN/30给出。还使用Rps（每秒转数），此时角速度为2πN。 |
| Screw displacement | 螺杆位移 |
A rotation of a rigid body about an axis accompanied by a translation of the body along the same axis. 刚体绕轴旋转，同时刚体沿同一轴平移。 |
| Stress corrosion cracking (SCC) | 应力腐蚀开裂（SCC） |
A common form of Stress cracking in which an Electrolyte encourages the growth of a crack in a highly stressed bolt. Only a tiny quantity of electrolyte need be present, at the tip or face of the crack. A time-dependent process in which a metallurgically susceptible material fractures prematurely under conditions of simultaneous corrosion and sustained loading at lower stress levels than would be required in the absence of a corrosive environment. Tensile stress is required at the metal surface and may be a residual stress resulting from heat treatment or fabrication of the metal or the result of external loading. Cracking may be intergranular or transgranular, depending on the combination of alloy and environment. 一种常见的应力开裂形式，其中电解液促使高应力螺栓中的裂纹扩展。在裂纹尖端或表面，只需存在少量电解质。一种随时间变化的过程，其中冶金敏感材料在同时腐蚀和持续加载的条件下过早断裂，其应力水平低于无腐蚀环境时的要求。在金属表面需要拉应力，拉应力可以是金属的热处理或制造或外部负载产生的残余应力。裂纹可能是沿晶开裂或穿晶开裂，这取决于合金和环境的组合。 |
| 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。 |
| Fracture toughness | 断裂韧性 |
A generic term for measures of resistance to extension of a crack. The term is sometimes restricted to results of fracture mechanics tests, which are directly applicable in fracture control. However, the term commonly includes results from simple tests of notched or precracked specimens not based on fracture mechanics analysis. Results from tests of the latter type are often useful for fracture control, based on either service experience or empirical correlations with fracture mechanics tests. 裂纹扩展阻力测量的通用术语。该术语有时仅限于断裂力学试验的结果，这些结果直接适用于断裂控制。该术语通常包括非基于断裂力学分析的切口或预裂纹试样的简单试验结果。基于使用经验或与断裂力学试验的经验相关性，后一类试验的结果通常有助于断裂控制。 |
| Torque monitor | 扭矩监测器 |
A torque tool control system which monitors the amount of torque being developed by the tool during use, but does not control the tool or the torque produced. 一种扭矩工具控制系统，监控工具在使用过程中产生的扭矩量，但不控制工具或产生的扭矩。 |
| Strength (Unit Pa) | 强度（单位Pa） |
The maximum stress, in tension, compression, shear, or combinations thereof, that may be monotonically applied to a material, component, or structure before failure (defined as fracture, yielding, buckling, etc. as appropriate). 在破坏前（视情况定义为断裂、屈服、屈曲等），材料、部件或结构在拉伸、压缩、剪切或其组合中可能单调施加的最大应力。 |
| Ventilation | 通风系统 |
A system for circulating fresh air in a room, building, passenger vehicle, orother enclosed space. 在房间、建筑物、乘用车或其他封闭空间中循环新鲜空气的系统。 |
| Air conditioning | 空调 |
The process of controlling the temperature and humidity in rooms, buildings, aircraft, passenger vehicles, etc. More generally it includes control of dust, levels of radiant heat, etc. 控制房间、建筑物、飞机、客运车辆等的温度和湿度的过程。更一般地说，它包括控制灰尘、辐射热水平等。 |
| Prevailing torque | 有效扭矩 |
Torque required to run a nut down against the joint when some obstruction, such as a plastic insert in the threads, or a noncircular thread, or other, has been introduced to help the fastener resist vibration loosening. Prevailing torque, unlike normal torque on a nut or bolt, is not proportional to the Preload in the fastener. 当引入了一些障碍物（如螺纹中的塑料插件或非圆螺纹或其他障碍物）以帮助紧固件抵抗振动松动时，将螺母向下压靠接头所需的扭矩。与螺母或螺栓上的正常扭矩不同，主要扭矩与紧固件中的预载不成比例。 |
| 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。 |
| Closed-die forging | 闭模锻造 |
The forming of a workpiece by compression within a pair of dies having the female form of the component to be manufactured (closed dies), superfluous metal being expelled as flash where the dies meet. 在一对具有待制造部件的阴模的模具（闭模）内通过压缩形成工件，多余的金属在模具相遇处作为飞边排出。 |
| 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。 |
| 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。 |
| Head height | 头部高度 |
The head height shall be that overall distance measured parallel to the axis of the product from the top of the head to the bearing surface and shall include the thickness of the washer face. Raised grade and manufacturer’s identification are excluded from head height. 头部高度应为平行于产品轴线从封头顶部到支承面测量的总距离，并应包括垫圈表面的厚度。提升等级和制造商标识不包括在头部高度中。 |
| Threading machine | 螺纹机 |
A machine used to cut an external thread on a rod, tube, bolt blank, etc. or an internal thread in a hole, tube, nut blank, etc. 用于切割杆、管、螺栓毛坯等上的外螺纹或孔、管、螺母毛坯等中的内螺纹的机器。 |
| Flange | 法兰 |
Flange refers to a head style for bolts where there is a circular ‘flange’ under the head that acts like a washer to distribute a load. A flange is a projected flat rim or collar. 1. Annular rims at the ends of pipes (flanged pipe) or shafts by which they may be coupled together using bolts that pass through holes in the flanges (flange coupling, flange union), or by toggle clamps around the periphery. 2. An extended rim on a wheel that positions it laterally on a track. Commonly used for railway rolling stock. 3. The top and bottom parts of an I-beam. 法兰是指螺栓的头部样式，其中头部下方有一个圆形“法兰”，其作用类似于垫圈以分配载荷。凸缘是凸出的平轮辋或凸缘。1.管道（法兰管）或轴端部的环形边缘，通过这些边缘，可以使用穿过法兰孔的螺栓（法兰联轴器、法兰接头）或通过周边的肘节夹将管道连接在一起。2.车轮上的延伸轮辋，将其横向定位在轨道上。通常用于铁路车辆。3.工字梁的顶部和底部。 |
| Tolerances | 公差 |
A fractional allowance for variation from the specifications. In mass production, using automatic machines, parts are intended to be completely or partially interchangeable, and in batch production parts should ideally fit without the need for selection. In practice it is impossible for mass-produced parts to have exactly the same size, owing to tool wear, variations in raw materials, thermal effects, etc. In consequence, variations from exactness, termed tolerances, are assigned to what is permissible on the basic size. 与规范不同的部分公差。在大规模生产中，使用自动机器时，零件应完全或部分可互换，在批量生产中，零件应理想匹配，无需选择。在实践中，由于刀具磨损、原材料变化、热效应等原因，批量生产的零件不可能具有完全相同的尺寸。因此，将精度偏差（称为公差）指定给基本尺寸上允许的尺寸。 |
| Striation | 条纹组织 |
A fatigue fracture feature, often observed in electron micrographs, that indicates the position of the crack front after each succeeding cycle of stress. The distance between striations indicates the advance of the crack front across that crystal during one stress cycle, and a line normal to the striation indicates the direction of local crack propagation. 一种疲劳断裂特征，通常在电子显微照片中观察到，表明每次应力循环后裂纹前沿的位置。条纹之间的距离表示在一个应力循环期间裂纹前沿穿过该晶体的前进，垂直于条纹的线表示局部裂纹扩展的方向。 |
| British thermal unit (BTU, Btu) | 英热单位（BTU，Btu） |
An obsolete (non-SI) imperial unit of energy defined as the energy required to raise the temperature of one pound of pure water at 68°F by 1°F. The conversion to SI is 1 Btu = 1.055 056 × 103 J. 一种已被淘汰的（非SI）英制能量单位，定义为将68°F的一磅纯水的温度升高1°F所需的能量。转换为SI为1Btu=1.055056×103J。 |
| Subcritical annealing | 不完全退火 |
A process anneal performed on ferrous alloys at a temperature below Ac1. 在低于Ac1的温度下对铁合金进行的工艺退火。 |
| Ball mill | 球磨机 |
A mill for grinding and pulverizing materials, consisting of a horizontal rotating drum containing loose steel or ceramic balls. 一种用于研磨和粉碎物料的磨机，由装有松散钢球或陶瓷球的水平旋转滚筒组成。 |
| Equation, short form | 方程式，简写形式 |
An empirical equation which relates the torque applied to the bolt to the preload created in it, and which depends mainly on an experimentally derived factor called the Nut factor. 一个经验公式，将施加在螺栓上的扭矩与螺栓中产生的预载荷联系起来，主要取决于一个称为螺母系数的实验得出的系数。 |
| Deflection temperature under load (DTUL) | 负载变形温度（DTUL） |
The temperature at which a simple cantilever beam deflects a given amount under load. Formerly called heat distortion temperature. 简单悬臂梁在负载下偏转给定量的温度。以前称为热变形温度。 |
| Anneal to temper | 退火回火 |
A final partial anneal that softens a cold worked nonferrous alloy to a specified level of hardness or tensile strength. 将冷加工的有色金属合金软化到规定的硬度或抗拉强度水平的最终局部退火。 |
| Austenitic grain size | 奥氏体晶粒尺寸 |
The size attained by the grains of steel when heated to the austenitic region; may be revealed by appropriate etching of cross sections after cooling to room temperature. 当加热到奥氏体区域时钢晶粒达到的尺寸；冷却至室温后，可通过适当蚀刻横截面来显示。 |
| Condensate strainer | 冷凝水过滤器 |
A filter in a steam plant used to remove particulate matter from condensate before it is added to feedwater. 蒸汽设备中的过滤器，用于在将冷凝水添加到给水中之前去除冷凝水中的颗粒物。 |
| Active vibration suppression | 主动振动抑制 |
The reduction of undesirable vibration in components by feedback control. 通过反馈控制减少部件中的不良振动。 |
| 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。 |
| Hot stamping | 热冲压 |
Hot forging of brass and bronze alloys. 黄铜和青铜合金的热锻。 |
| Hot-wire test | 热线测试 |
Method used to test heat extraction rates of various quenchants. Faster heat-extracting quenchants will permit more electric current to pass through a standard wire because it is cooled more quickly. Compare with hot-wire analyzer. 用于测试各种淬火剂的热提取率的方法。与热线分析仪相比，更快的热提取淬火剂将允许更多电流通过标准导线，因为标准导线冷却更快。 |
| Initial preload | 初始预载 |
The tension created in a single bolt as it is tightened. Will usually be modified by subsequent assembly operations or by in-service loads and conditions. 拧紧单个螺栓时产生的张力。通常会通过后续的装配操作或在役负载和条件进行修改。 |
| Sample median | 样本中间值 |
The middle value when all observed values in a sample are arranged in order of magnitude. If an even number of samples are tested, the average of the two middlemost values is used. It is a point estimate of the population median, or 50% point. 当样本中的所有观测值按数量级排列时的中间值。如果测试的样本数为偶数，则使用两个中间值的平均值。这是人口中位数的一个点估计值，或50%的点。 |
| 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。 |
| Tensile stress (Unit Pa) | 拉应力（单位Pa） |
A stress that causes two parts of an elastic body, on either side of a typical stress plane, to pull apart. A stress that tends to stretch a component, or local region of a component, when under load. In simple tension it results from the applied axial load, but tensile stresses occur in bending, torsion and other forms of loading. 一种应力，使弹性体的两个部分在典型应力平面的任一侧分离。在负载下，倾向于拉伸部件或部件局部区域的应力。在简单拉伸中，它由施加的轴向载荷产生，但拉伸应力发生在弯曲、扭转和其他形式的载荷中。 |
| Actual power | 实际功率 |
(actual horsepower) (Unit W or hp) The power delivered at the output shaft of an engine, before subsequent transmission through a gearbox etc. （实际马力）（单位W或hp）在随后通过变速箱等传输之前，在发动机输出轴上传递的功率。 |
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