| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Heat-capacity ratio (c*) | 热容量比（c*） |
A non-dimensional parameter that arises in the analysis of heat exchangers, defined as the ratio cMIN/cMAX where cMIN is the heat-capacity rate c for the fluid with the smaller value of c and cMAX the value for the fluid with the larger value of c. Different flow rates and specific-heat values give rise to different values for c. 热交换器分析中出现的无量纲参数，定义为比率cMIN/cMAX其中cMIN是流体的热容率c，c值较小，cMAX是流体的值具有较大的c值。不同的流速和比热值产生不同的c值。 |
| 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。 |
| Oxidation | 氧化 |
(1) A reaction in which there is an increase in valence resulting from a loss of electrons. (2) A corrosion reaction in which the corroded metal forms an oxide; usually applied to reaction with a gas containing elemental oxygen, such as air. （1）因电子损失而导致价态增加的反应。（2）腐蚀反应，其中被腐蚀的金属形成氧化物；通常用于与含有元素氧的气体如空气反应。 |
| 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。 |
| Thermocouple | 热电偶 |
A device for measuring temperature, consisting of lengths of two dissimilar metals or alloys that are electrically joined at one end and connected to a voltage-measuring instrument at the other end. When one junction is hotter than the other, a thermal electromotive force is produced that is roughly proportional to the difference in temperature between the hot and cold junctions. 一种测量温度的装置，由两种不同的金属或合金组成，一端电连接，另一端与电压测量仪相连。当一个结比另一个结更热时，产生的热电动势大致与热结和冷结之间的温差成比例。 |
| Dynamic mechanical measurement | 动态机械测量 |
A technique in which either the modulus and/or damping of a substance under oscillatory load or displacement is measured as a function of temperature, frequency, or time, or a combination thereof. 一种技术，其中在振荡载荷或位移下测量物质的模量和/或阻尼作为温度、频率或时间或其组合的函数。 |
| Angle of torsion | 扭转角 |
(angle of twist) (Unit ° or rad) The angle relative to a chosen section, normal to the axis of twist, through which another part of a component rotates when subjected to a torque. （扭转角）（单位°或弧度）相对于选定截面的角度，垂直于扭转轴，部件的另一部分在受到扭矩时通过该角度旋转。 |
| Significance level | 显着性水平 |
The stated probability (risk) that a given test of significance will reject the hypothesis that a specified effect is absent when the hypothesis is true. 当假设为真时，给定的显著性检验将拒绝特定效应不存在的假设的所述概率（风险）。 |
| 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。 |
| 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。 |
| Bolt gage | 螺栓量规 |
An ultrasonic instrument used to measure the stress or strain in bolts. 用于测量螺栓应力或应变的超声波仪器。 |
| 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。 |
| Repeatability | 重复性 |
A term used to refer to the test-result variability associated with a limited set of specifically defined sources of variability within a single laboratory. 一个术语，用于指与单个实验室内一组有限的特定变异源相关的测试结果变异性。 |
| Width across flats | 平面宽度 |
A principal dimension of nuts, or of bolt heads. Work hardening The slight increase in hardness and strength produced when a body is loaded past its yield point. Also called strain hardening. 螺母或螺栓头的主要尺寸。加工硬化：当物体被加载超过其屈服点时，硬度和强度略有增加。也称为应变硬化。 |
| Lubricant | 润滑剂 |
Any substance interposed between two surfaces for the purpose of reducing the friction or wear between them. 为了减少两个表面之间的摩擦或磨损而置于两个表面间的任何物质。 |
| 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。 |
| Frequency | 频率 |
(temporal frequency, f) (Unit Hz) The number of cycles per second in an oscillation or the repetition rate for a cyclic process. （时间频率，f）（单位Hz）振荡中每秒的周期数或循环过程的重复率。 |
| Starting friction | 起动摩擦 |
(limiting friction, static friction, stiction) (Unit N) The force required to initiate movement between two bodies in contact. （极限摩擦力、静摩擦力、粘滞）（单位N）在两个接触物体之间启动运动所需的力。 |
| T-slot | T型槽 |
A recessed or undercut slot made with a special T shaped cutter in the tables of machine tools to receive the square head of a T bolt for clamping workpiece. 在机床工作台上用一种特殊的T形刀具制成的凹槽或底切槽，用于容纳T形螺栓的方头，用于夹紧工件。 |
| Centrifugal clutch | 离心离合器 |
A clutch that engages and disengages at a defined speed of rotation of the driving shaft, as when expanding friction shoes act against the inside of a drum. 一种离合器，以驱动轴规定的旋转速度接合和分离，如当膨胀的摩擦片作用在滚筒内部时。 |
| Imperial system of units | 英制单位 |
British imperial system of units) An obsolete system of units first defined in the British Weights and Measures Act of 1824. Its three base units were second (time), yard (length), and pound avoirdupois (mass). The imperial unit of capacity was the gallon. The many associated units introduced subsequently include cubic inch, cubic foot, cubic yard, pint, and quart for both liquid and dry measures of capacity (i.e. volume); ounce, hundredweight, short and long ton for avoirdupois mass; poundal for force; minute and hour for time; fahrenheit for temperature; and British thermal unit for energy. Closely related to the imperial system of units is the US customary system of units. Each imperial unit is now legally defined in terms of the metric (i.e. SI) equivalent. （英帝国单位制）1824年英国度量衡法首次定义的已被淘汰的单位制。其三个基本单位为秒（时间）、码（长度）和磅（质量）。容量的英制单位是加仑。随后引入的许多相关单位包括立方英寸、立方英尺、立方码、品脱和夸脱，用于液体和干燥容量测量（即体积）；盎司，百分之一百重量，短吨和长吨，以保证重量；磅达表示力；以分钟和小时表示时间；华氏温度；英国热能单位。与帝国单位制密切相关的是美国习惯单位制。现在，每个英制单位在法律上都是以公制（即SI）当量来定义的。 |
| 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。 |
| 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。 |
| Screw area (Unit m²) | 螺丝面积（单位m²） |
The area of a circle described by the tips of a propeller. 螺旋桨尖端所描述的圆的面积。 |
| Crystalline defects | 结晶缺陷 |
The deviations from a perfect three-dimensional atomic packing that are responsible for much of the structure-sensitive properties of the materials. Crystal defects can be point defects (dislocations) or surface defects (vacancies), line defects (dislocations), or surface defects (grain boundaries). 与完美的三维原子堆积的偏差是造成材料的大部分结构敏感特性的原因。晶体缺陷可以是点缺陷（位错）或表面缺陷（空位）、线缺陷（位错）或表面缺陷（晶界）。 |
| 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。 |
| Laser sintering | 激光烧结 |
A manufacturing technique by which parts are built layer by layer (each typically 20 μm thick) from plastic or metal (Direct Metal Laser Sintering, DMLS) material in powder form, each layer being sintered by a scanning laser. 一种制造技术，通过这种制造技术，零件由粉末形式的塑料或金属（直接金属激光烧结，DMLS）材料逐层（每个厚度通常为 20 微米）构建，每一层都由扫描激光烧结。 |
| 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。 |
| 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。 |
| Tightness, acceptable | 密封性，可接受的 |
Wholly leak-free joints are impossible, at least if the contained fluid is a gas, so it has been proposed that the design of a gasketed joint should start with the selection of an ‘‘acceptable’’ leak rate. The designer would dimension bolts and joint members so that the actual leak rate would never exceed this. Three standard levels of tightness have been proposed as well. 至少在所含流体为气体的情况下，完全无泄漏的接头是不可能的，因此有人建议，垫圈接头的设计应从选择“可接受”的泄漏率开始。设计师将确定螺栓和接头构件的尺寸，以便实际泄漏率永远不会超过此值。还提出了三种标准的密封性等级。 |
| Base metal hardness | 母材硬度 |
Hardness closest to the surface (when traversing from core to outside diameter) just before an increase or decrease occurs, denoting, respectively, carburization or decarburization. 在发生增加或减少之前最接近表面的硬度（从芯部到外径时），分别表示渗碳或脱碳。 |
| Anti-freeze | 防冻液 |
A substance such as ethylene glycol added to the cooling system of a watercooled engine to lower the freezing point of the cooling water and also inhibit the formation of rust and other deposits. 一种物质，如乙二醇，添加到水冷发动机的冷却系统中，以降低冷却水的冰点，并抑制生锈和其他沉积物的形成。 |
| Thread grinding | 螺纹磨削 |
A method for producing or finishing very precise screw threads using a profiled grinding wheel. 一种使用异形砂轮生产或精加工非常精密螺纹的方法。 |
| Notch depth | 缺口深度 |
The distance from the surface of a notched test specimen to the bottom of the notch. In a cylindrical test specimen, the percentage of the original cross-sectional area removed by machining an annular groove. 从缺口试样表面到缺口底部的距离。在圆柱形试样中，通过加工环形槽去除的原始横截面积的百分比。 |
| Gearbox | 变速箱 |
A mechanism consisting of meshing gears which transmit power and torque to an output shaft from an input shaft directly connected to an engine. The mechanism is normally contained within a casing filled with lubricating oil. The diagram shows a simple four-speed sliding-mesh gearbox in which gears with different numbers of teeth are slid along parallel splined shafts within the gearbox to mesh with each other and change the ratio of output to input speed (gear ratio). 一种由啮合齿轮组成的机构，将动力和扭矩从直接连接到发动机的输入轴传递到输出轴。该机构通常包含在充满润滑油的外壳内。示例一个简单的四速滑动啮合齿轮箱，其中具有不同齿数的齿轮沿着齿轮箱内的平行花键轴滑动，以相互啮合并改变输出与输入速度的比率（齿轮比）。 |
| Air-cooled condenser | 风冷冷凝器 |
A heat exchanger, in which the cooling medium is air, used to condense the exhaust steam from a steam turbine, the condensate being returned to the boiler. 一种热交换器，其中冷却介质为空气，用于冷凝蒸汽轮机排出的蒸汽，冷凝水返回锅炉。 |
| Tension | 拉伸 |
The force or load that produces elongation. 1. The condition in a bar, belt, cable, spring, string, wire, etc. that is being pulled from either end. 2. (tensile force) (unit N) The force associated with tension as in (1). It is measured by a tension meter. 伸长力产生伸长的力或载荷。1.从两端拉出的杆、带、电缆、弹簧、线、线等的状态。2.（张力）（单位N）与张力相关的力。 |
| Yield point (Unit Pa) | 屈服点（单位Pa） |
The first stress in a material, usually less than the maximum attainable stress, at which an increase in strain occurs without an increase in stress. Only certain metals—those which exhibit a localized, heterogeneous type of transition from elastic to plastic deformation—produce a yield point. If there is a decrease in stress after yielding, a distinction may be made between upper and lower yield points. The load at which a sudden drop in the flow curve occurs is called the upper yield point. The constant load shown on the flow curve is the lower yield point. (yield strength, yield stress, Rel, Rel) The stress at which the onset of permanent (plastic) deformation (yielding) occurs in a body under increasing loading. In some materials, a yield-point phenomenon occurs in which stress falls on initial yielding and plastic deformation continues without increase in stress as strain increases further. The yield criterion is the combination of normal and shear stresses which produces yielding under multiaxial loading. 材料中的第一应力，通常小于可达到的最大应力，在该应力下应变增加而应力不增加。只有某些金属——表现出从弹性变形到塑性变形的局部、非均匀类型的金属——才会产生屈服点。如果屈服后应力降低，可区分上屈服点和下屈服点。流量曲线突然下降时的荷载称为上屈服点。流量曲线上显示的恒定载荷为较低屈服点。（屈服强度，屈服应力，Rel）在不断增加的载荷下，物体发生永久（塑性）变形（屈服）时的应力。在某些材料中，会出现屈服点现象，即应力在初始屈服时下降，随着应变进一步增加，塑性变形继续，而应力没有增加。屈服准则是在多轴载荷下产生屈服的正应力和剪应力的组合。 |
| Roughness | 粗糙度 |
The deviations from the wavy surface itself, caused by geometry of the cutting tool and its wear, machining conditions, microstructure of the workpiece, vibrations in the system, and so on. Surface roughness changes as a surface goes through the wearing-in process, but may then stabilize. 由刀具的几何形状及其磨损、加工条件、工件的微观结构、系统中的振动等引起的与波状表面本身的偏差。表面粗糙度随着表面经过磨合过程而变化，但随后可能会稳定下来。 |
| 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。 |
| Tensiometer | 张力计 |
An instrument used to measure surface tension. 用来测量表面张力的仪器。 |
| Transmission dynamometer | 传动测功机 |
A dynamometer in which the power transmitted by a shaft is obtained from the product of its rotation speed and the torque determined from measured shear strains along the shaft. 一种测功机，其中轴传递的功率由其转速和扭矩的乘积获得，扭矩由沿轴测得的剪切应变确定。 |
| Pressure recovery (Unit Pa) | 压力恢复（单位Pa） |
The progressive increase in static pressure for unseparated flow through a diverging nozzle or diffuser. 通过发散喷嘴或扩散器的未分离流的静压逐渐增加。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Metre (m) | 米（m） |
The base unit of length in the SI system. It is equal to the distance travelled by light in vacuum in 1/299 792 458 seconds. SI系统中长度的基本单位。它等于光在真空中在1/299792458秒内传播的距离。 |
| 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。 |
| Mechatronics | 机电一体化 |
The integration of mechanical engineering, electrical engineering, electronic engineering, and software engineering. 机械工程、电气工程、电子工程和软件工程的集成。 |
| Assembly drawing | 装配图纸 |
An engineering drawing that shows how parts are assembled to produce a component or a complete machine. It may include sections to show internal features, dimensions that are critical for assembly, manufacturing information, and part numbers. 显示零件如何组装以生产组件或整机的工程图。它可能包括显示内部特征、对装配至关重要的尺寸、制造信息和零件编号的部分。 |
| 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。 |
| 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 |
| 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。 |
| 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。 |
| 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。 |
| Progressive aging | 渐进时效 |
Aging by increasing the temperature in steps or continuously during the aging cycle. 通过在时效周期中逐步或连续升高温度进行增加时效。 |
| Wear rate | 磨损率 |
The rate of material removal or dimensional change due to wear per unit of exposure parameter—for example, quantity of material removed(mass, volume, thickness) in unit distance of sliding or unit time. 由于单位暴露参数的磨损而导致的材料去除率或尺寸变化，例如，单位滑动距离或单位时间内去除的材料数量（质量、体积、厚度）。 |
| 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。 |
| Radian (rad) | 弧度（rad） |
A coherent derived SI unit defined as the plane angle subtended at the centre of a circle by an arc having a length equal to the radius. Thus 2π radians are equivalent to 360° and 1 rad ≈ 57.3°. 一种相干导出的国际单位制单位，定义为在圆心处被长度等于半径的弧对向的平面角。因此，2π弧度相当于360°和1弧度≈57.3°. |
| Brittle fracture | 脆性断裂 |
The fracture of a component or structure in the globally-elastic range of loading, so that the broken pieces may be refitted to regain the original article. Separation of a solid accompanied by little or no macroscopic plastic deformation. Typically, brittle fracture occurs by rapid crack propagation with less expenditure of energy than for ductile fracture. 部件或结构在全局弹性载荷范围内的断裂，以便可以将破碎的碎片重新装配以恢复原始物品。固体的分离伴随着很少或没有宏观塑性变形。通常，脆性断裂通过快速裂纹扩展发生，能量消耗比韧性断裂少。 |
| Thermal electromotive force | 热电动势 |
The electromotive force generated in a circuit containing two dissimilar metals when one junction is at a temperature different from that of the other. 当一个结处于不同于另一个结的温度时，在含有两种不同金属的电路中产生的电动势。 |
| 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。 |
| Secondary hardening | 二次硬化 |
The process whereby some low-alloy steels, quenched to produce martensite, produce fine precipitates when tempered above 550°C, which inhibit dislocation motion and reverse the trend towards lower strength at higher tempering temperatures. 某些低合金钢经淬火产生马氏体，在550°C以上回火时产生细小沉淀的过程，这抑制了位错运动，扭转了在较高回火温度下强度降低的趋势。 |
| Elastic limit | 弹性极限 |
The maximum stress which a material is capable of sustaining without any permanent strain (deformation) remaining on complete release of the stress. 材料在完全释放应力时能够承受的最大应力，且不会留下任何永久应变（变形）。 |
| 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。 |
| 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。 |
| 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。 |
| 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。 |
| Blank carburizing | 毛坯渗碳 |
Simulating the carburizing operation without introducing carbon. This is usually accomplished by using an inert material in place of the carburizing agent, or by applying a suitable protective coating to the ferrous alloy. 在不引入碳的情况下模拟渗碳操作。这通常通过使用惰性材料代替渗碳剂或通过在铁合金上施加合适的保护涂层来实现。 |
| 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。 |
| Uniaxial strain | 单轴应变 |
Increase (or decrease) in length resulting from a stress acting parallel to the longitudinal axis of the specimen. 由平行于试样纵轴的应力引起的长度增加（或减少）。 |
| 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。 |
| Stress cycle | 应力循环 |
The smallest segment of the stress-time function that is repeated periodically. 周期性重复的应力时间函数的最小段。 |
| Clevis | U形夹 |
A U-shaped hook with holes at the ends through which a retaining bolt or pin (clevis pin) passes. 一种U形钩，末端有孔，固定螺栓或销（U形销）穿过这些孔。 |
| 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。 |
| Artificial aging | 人工时效 |
Aging above room temperature. 在室温以上的时效。 |
| Tension joint | 张力接头 |
A joint which is primarily subjected to loads acting more or less parallel to the axes of the bolts. 主要承受或多或少平行于螺栓轴线的载荷的接头。 |
| Malleable cast iron | 可锻铸铁 |
A cast iron made by prolonged annealing of white cast iron in which decarburization or graphitization, or both, take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface, hence, “whiteheart malleable;” otherwise, the fracture surface will be dark, hence, “blackheart malleable.” Ferritic malleable has a predominantly ferritic matrix; pearlitic malleable may contain pearlitic, spheroidite or tempered martensite depending on heat treatment and desired hardness. 白口铸铁一种通过长时间退火制成的铸铁，脱碳，石墨化，或两者都发生，以消除部分或全部渗碳体。石墨是回火碳的形式。如果脱碳是主要反应，产品将呈现出较轻的断裂表面，“白心可锻”。否则，断裂表面将变暗，“黑心可锻”。铁素体可锻性材料主要为铁素体基体；根据热处理和所需硬度，珠光体可锻材料可能包含珠光体、球状体或回火马氏体。 |
| 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。 |
| 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。 |
| Impact strength | 冲击强度 |
The resiliency or toughness of a solid as measured by impact energy. 用冲击能量测量的固体的弹性或韧性。 |
| 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）。 |
| Pressure ratio | 压力比 |
One pressure divided by another which may be a reference pressure. In many flow and thermodynamic processes, the pressure ratio is more important than the absolute pressure levels. For example, in compressible gas flow the Mach number is determined by the ratio of the stagnation pressure to the static pressure. 一个压力除以另一个压力，该压力可以是参考压力。在许多流动和热力学过程中，压力比比绝对压力水平更重要。例如，在可压缩气流中，马赫数由停滞压力与静压之比决定。 |
| Hydrogen damage | 氢损伤 |
A general term for the embrittlement, cracking, blistering, and hydride formation that can occur when hydrogen is present in some metals. 当氢存在于某些金属中时可能发生的脆化、开裂、起泡和氢化物形成的总称。 |
| Interrupted quenching | 间断淬火 |
A quenching procedure in which the workpiece is removed from the first quench at a temperature substantially higher than that of the quenchant and is then subjected to a second quenching system having a different cooling rate than the first. 在该淬火过程中，工件在显著高于淬火剂的温度下从第一次淬火中取出，然后经受具有不同于第一次淬火的冷却速率的第二次淬火系统。 |
| 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。 |
| Rockwell superficial hardness test | 洛氏表面硬度试验 |
Same as Rockwell hardness test, except that smaller minor and major loads are used. 与洛氏硬度测试相同，只是使用较小的次要载荷和主要载荷。 |
| Maximum stress (Smax) | 最大应力（Smax） |
The stress having the highest algebraic value in the stress cycle, tensile stress being considered positive and compressive stress negative. The nominal stress is used most commonly. 在应力循环中具有最高代数值的应力，拉应力被认为是正的，压应力被认为是负的。名义应力是最常用的。 |
| 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。 |
| Carburizing | 渗碳 |
Absorption and diffusion of carbon into solid ferrous alloys by heating, to a temperature usually above Ac3, in contact with a suitable carbonaceous material. A form of case hardening that produces a carbon gradient extending inward from the surface, enabling the surface layer to be hardened either by quenching directly from the carburizing temperature or by cooling to room temperature, then reaustenitizing and quenching. 通过与合适的含碳材料接触加热至通常高于Ac3的温度，将碳吸收和扩散到固体铁合金中。一种表面硬化形式，产生从表面向内延伸的碳梯度，通过直接从渗碳温度淬火或冷却至室温，然后重新奥氏体化和淬火，使表层硬化。 |
| 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。 |
| 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。 |
| 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。 |
| 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）。 |
| 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。 |
| 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。 |
| Aging treatment | 时效处理 |
Heat treatment aimed at age hardening; it comprises solution and precipitation treatments. 针对时效硬化的热处理；它包括溶液和沉淀处理。 |
| 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”。 |
| Elastic resilience | 弹性回弹 |
The amount of energy absorbed in stressing a material up to the elastic limit; or, the amount of energy that can be recovered when stress is released from the elastic limit. 向材料施加应力直至弹性极限所吸收的能量；或者当应力从弹性极限释放时可以恢复的能量值。 |
| 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。 |
| Oil quenching | 油淬 |
Hardening of carbon steel in an oil bath. Oils are categorized as conventional, fast, martempering, or hot quenching. 碳钢在油浴中的硬化。分为常规、快速、马氏体淬火或热淬火。 |
| Clutch | 离合器 |
A device for connecting and disconnecting rotating shafts, for example between an engine and a gearbox. 一种用于连接和断开旋转轴的装置，例如在发动机和变速箱之间。 |
| 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。 |
| Austenitizing | 奥氏体化 |
Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing). When used without qualification, the term implies complete austenitizing. 通过将铁合金加热到转变范围（部分奥氏体化）或高于转变范围（完全奥氏体化）来形成奥氏体。当不加限定地使用时，该术语意味着完全奥氏体化。 |
| 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。 |
| Dew point analyzer | 露点分析仪 |
An atmosphere monitoring device that measures the partial pressure of water vapor in an atmosphere. 一种大气监测装置，用于测量大气中水蒸气的分压。 |
| Effective radius of nut, bolt head, or threads | 螺母、螺栓头或螺纹的有效半径 |
Distance between the geometric center of the part and the circle of points through which the resultant contact forces between mating parts passes. Must be determined by integration. 零件几何中心与配合零件之间的合力通过的点圆之间的距离。必须通过积分来确定。 |
| Size effect | 尺寸效应 |
Effect of the dimensions of a piece of metal on its mechanical and other properties and on manufacturing variables such as forging reduction and heat treatment. In general, the mechanical properties are lower for a larger size. 金属件的尺寸对其机械和其他性能以及对制造变量（如锻造、压下和热处理）的影响。一般来说，尺寸越大，机械性能越低。 |
| 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。 |
| Viscoelasticity | 粘弹性 |
A property involving a combination of elastic and viscous behavior. A material having this property is considered to combine the features of a perfectly elastic solid and a perfect fluid. A phenomenon of time-dependent, in addition to elastic, deformation (or recovery) in response to load. 结合弹性和粘性的特性。具有这种性质的材料被认为是完美弹性固体和完美流体的结合体。除了弹性变形（或恢复）外，还随时间变化的一种现象。 |
| Engineering stress (s) | 工程应力 |
A term sometimes used for conventional stress in order to differentiate it from true stress. In tension testing, it is calculated by dividing the breaking load applied to the specimen by the original crosssectional area of the specimen. 一个术语，有时用于常规应力，以区别于真实应力。在拉伸试验中，通过将施加在试样上的断裂载荷除以试样的原始横截面积来计算。 |
| 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。 |
| 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。 |
| Constant-force spring | 恒力弹簧 |
A spring that has the same restoring force regardless of displacement. The most common type takes the form of a coiled strip that, owing to tight coiling during manufacture, is pre-stressed (a steel measuring tape is an example). The uncoiling force is approximately constant as the change of curvature of the strip is approximately constant. Not to be confused with a clockwork spring from which power can be obtained. 无论位移如何，具有相同恢复力的弹簧。最常见的类型是卷绕带，由于制造过程中的紧密卷绕，该卷绕带是预应力的（钢卷尺就是一个例子）。随着带材曲率的变化近似恒定，开卷力近似恒定。不要与可获得动力的发条弹簧混淆。 |
| 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。 |
| Dynamic load rating (Unit N) | 额定动载荷（单位N） |
The allowable load on a component or structure when the loading is not static. 当负载不是静态时，组件或结构上的允许负载。 |
| Two-stroke engine | 二冲程发动机 |
(two-cycle engine) A petrol or diesel engine in which an air/fuel charge is introduced through an induction port, compressed and burned, expanded and then exhausted through an exhaust port. The two ports in the cylinder wall are opened and closed by the piston. There are two strokes in each revolution of the crankshaft. In total-loss lubrication petrol engines, the lubricating oil is mixed with the fuel. （双循环发动机）一种汽油或柴油发动机，其中空气/燃料通过进气口引入，压缩和燃烧，膨胀，然后通过排气口排出。气缸壁上的两个口由活塞打开和关闭。曲轴每转一圈有两个冲程。在全失润滑汽油发动机中，润滑油与燃油混合。 |
| Screw | 螺钉 |
Threaded fastener designed to be used in a tapped or untapped (e.g., wood screw) hole, but not with a nut. A fastener with a screw thread cut or rolled into its cylindrical or conical shank, intended either to cut its own thread (as in a wood screw) or engage in a threaded hole. A self-tapping screw (sheet-metal screw, tapping screw) has a sufficiently hard thread that it cuts an internal thread in thin sheet or a component made of soft material when driven into a hole in the sheet or component. The screw head is the part of a screw used to apply torque to the screw. Common screw-head designs are circular in cross section with a diametral slot or cross, or hexagonal and recessed with a cross or hexagon. A screw thread is one or more continuous helical grooves of uniform section along either the exterior surface (male thread) or the interior surface (female thread) of a cylindrical or conical body. The three-dimensional shape that results when the thread cross section is rotated and axially advanced along an axis is called a helicoid, the angle that the thread makes when projected on to the axis being called the angle of inclination. Threads are employed in fasteners such as bolts, nuts, and screws; location and measuring instruments; in power drives; in some electrical fittings (Edison thread); and on the ends of crankshafts to suppress oil leakage (thrower thread). Parallel threads are formed on cylinders; tapered threads on cones, typically with a taper rate of 1:16. A screw with a righthanded thread appears to move away from the observer when turned clockwise. All standard screws, bolts and nuts have right-hand threads, but left-handed threads are sometimes employed. The axial distance between corresponding points on adjacent threads is called the screw pitch or screw rate and, for a single continuous helical groove (a single-start thread), is the same as the change in axial distance (the lead) between a nut and the head of a bolt during one revolution, the number of thread forms per mm then being the reciprocal of the pitch. For the same screw diameter, coarse threads have fewer threads per mm than fine threads. A multiple-start screw thread (usually coarse, see later) consists of two or more identical threads running simultaneously along its axis so as to provide greater bearing area and greater velocity ratio. The starts are separated by 180° (double start), 120° (triple start), 90° (quadruple start) etc., depending upon the number of threads. Thus, in double-start threads, the lead is twice the pitch; and so on. The axial distance between corresponding points on two adjacent threads in a multiple start thread is called the divided pitch. The position on a screw thread where there is equal distance between the flanks on the solid part of the thread and in the space between the threads is the pitch point, the associated diameter of which is termed the pitch diameter. The basic nomenclature for threads, some of which is common with that for toothed gearing, is shown in the diagrams. A helix formed or cut on a cylindrical surface which may advance along the axis to the right or left. The helix may be single or multiple. 一种螺纹紧固件，设计用于攻丝或未攻丝（如木螺钉）孔，但不与螺母配合使用。其螺纹被切割或卷成圆柱形或锥形柄，用于切割自身螺纹（如木螺钉）或嵌入螺纹孔。自攻螺钉（钣金螺钉、自攻螺钉）具有足够硬的螺纹，当打入薄板或部件中的孔时，它会在薄板或软材料部件中切割内螺纹。螺钉头是螺钉的一部分，用于向螺钉施加扭矩。常见的螺钉头设计为横截面为圆形，带有直径槽或十字，或为六边形，并带有十字或六边形凹槽。螺纹是沿圆柱形或锥形体的外表面（外螺纹）或内表面（内螺纹）具有均匀截面的一个或多个连续螺旋槽。当螺纹横截面旋转并沿轴轴向前进时产生的三维形状称为螺旋面，螺纹投影到轴上时形成的角度称为倾角。螺纹用于紧固件，如螺栓、螺母和螺钉；定位和测量仪器；在动力驱动中；在一些电气配件中（爱迪生螺纹）；并安装在曲轴端部，以抑制漏油（抛掷器螺纹）。在圆柱体上形成平行螺纹；圆锥上的锥形螺纹，通常具有1:16的锥形率。当顺时针旋转时，具有右手螺纹的螺钉似乎会远离观察者。所有标准螺钉、螺栓和螺母都有右手螺纹，但有时使用左手螺纹。相邻螺纹上对应点之间的轴向距离称为螺距或螺纹率，对于单个连续螺旋槽（单个起始螺纹），与螺母和螺栓头之间的轴向间距（导程）在一周内的变化相同，每mm的螺纹形式数为螺距的倒数。对于相同的螺钉直径，粗螺纹的每毫米螺纹数少于细螺纹。多头螺纹（通常为粗螺纹，见下文）由两个或多个沿其轴线同时延伸的相同螺纹组成，以提供更大的承载面积和更大的速比。根据螺纹的数量，起点之间的间隔为180°（双起点）、120°（三起点）、90°（四起点）等。因此，在双起始螺纹中，导程是螺距的两倍；多起点螺纹中两个相邻螺纹上对应点之间的轴向距离称为分割螺距。螺纹上的位置，即螺纹实体部分的侧面和螺纹之间的空间之间的距离相等，即节点，其相关直径称为节径。图中显示了螺纹的基本术语，其中一些与齿轮传动的基本术语相同。在圆柱面上形成或切割的螺旋线，可沿轴线向右或向左前进。螺旋可以是单个或多个。 |
| 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。 |
| Specific heat capacity | 比热容 |
The heat necessary to raise the temperature of 1 kg of a substance by 1 K. It is measured in J/(kg K). 将1千克物质的温度升高1K所需的热量。单位为J/（kg K）。 |
| Total heat (Unit kJ) | 总热量（单位kJ） |
An alternative term for enthalpy. It is inappropriate as it suggests that it includes kinetic energy in the same way as total enthalpy, but it does not. Also, heat and enthalpy are quite different quantities, as their definitions show. 焓的另一个术语。这是不恰当的，因为它表明，它包括动能的方式与总焓相同，但它实际上并不是的。此外，热和焓是完全不同的量，正如它们的定义所示。 |
| Quench hardening | 淬火硬化 |
(1) Hardening suitable alpha-beta alloys (most often certain copper to titanium alloys) by solution treating and quenching to develop a martensitic-like structure. (2) In ferrous alloys, hardening by austenitizing and then cooling at a rate such that a substantial amount of austenite transforms to martensite. （1）通过固溶处理和淬火硬化合适的α-β合金（通常是某些铜-钛合金），以形成类似马氏体的结构。（2）在铁合金中，通过奥氏体化硬化，然后以一定速度冷却，使大量奥氏体转变为马氏体。 |
| Pressure rating (Unit Pa or bar) | 额定压力（单位Pa或bar） |
The internal pressure at which a pressure vessel, boiler, tank, piping, etc. is designed to operate safely. 压力容器、锅炉、储罐、管道等设计用于安全运行的内部压力。 |
| Mass flow meter | 质量流量计 |
An instrument, such as a Coriolis flow meter, which measures the mass flow rate of a fluid flowing through a pipe or other duct, rather than its volume flow rate. 一种仪器，例如科里奥利流量计，一种测量流经管道或其他管道的流体的质量流率而不是其体积流率的仪器。 |
| 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。 |
| Centi (c) | 厘（c） |
An SI unit prefix indicating a multiplier of 0.01; thus centimetre is a unit of length equal to one one-hundredth of a metre or 10 mm. 表示乘数0.01的SI单位前缀；因此厘米是长度单位，等于一米的百分之一或10毫米。 |
| 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。 |
| GGas turbine | G燃气轮机 |
An engine in which air, compressed by a multi-stage axial compressor and/or one or more centrifugal compressors, flows into a combustion chamber (or chambers) where fuel is burned and the hot gases then drive an axial turbine which powers the compressor. 由多级轴流压缩机和/或一个或多个离心压缩机压缩的空气流入燃烧室（或多个燃烧室），在燃烧室中燃烧燃料，然后热气体驱动轴流涡轮，为压缩机提供动力。 |
| Liquid carburizing | 液体渗碳 |
Surface hardening of steel by immersion into a molten bath consisting of cyanides and other salts. 通过浸入由氰化物和其他盐组成的熔池中对钢进行表面硬化。 |
| 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。 |
| Steel-wire rope | 钢丝绳 |
A rope or cable made up of many steel strands wrapped helically about an axis, each strand being made of metal wires twisted together like a helix. 一种绳索或缆绳，由许多绕轴螺旋缠绕的钢绞线组成，每根钢绞线由金属丝缠绕在一起形成螺旋。 |
| 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。 |
| Combined heat and power plant | 热电联产电厂 |
(CHP plant, COGEN, cogeneration plant, total-energy plant) A plant for the simultaneous production of more than one useful form of energy from the same energy source, such as process heat and electric power. In the arrangement shown, partially expanded steam is extracted from the steam turbine and used to produce process heat. （CHP工厂、COGEN、热电联产工厂、总能源工厂）从同一能源（如过程热能和电力）同时生产一种以上有用能源的工厂。在所示的布置中，部分膨胀的蒸汽从蒸汽轮机中提取并用于产生过程热量。 |
| 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。 |
| 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）。 |
| Allotropy | 同素异形体 |
A near synonym for polymorphism. Allotropy is generally restricted to describing polymorphic behavior in elements, terminal phases, and alloys whose behavior closely parallels that of the predominant constituent element. 多态性的近义词。同素异形体通常仅限于描述元素、终端相和合金中的多晶型行为，其行为与主要组成元素的行为非常相似。 |
| 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。 |
| Normal temperature and pressure (NTP) | 常温常压（NTP） |
Reference conditions defined by NIST as 20°C and 1 atm. NIST定义的参考条件为20°C和1atm。 |
| Sample percentage | 样本百分比 |
The percentage of observed values between two stated values of the variable under consideration. It is a point estimate of the percentage of the population between the same two stated values. 所考虑变量的两个规定值之间的观测值百分比。它是对相同两个规定值之间的总体百分比的点估计。 |
| Shell hardening | 壳型硬化 |
A surface-hardening process in which a suitable steel workpiece, when heated through and quench hardened, develops a martensitic layer or shell that closely follows the contour of the piece and surrounds a core of essentially pearlitic transformation product. This result is accomplished by a proper balance among section size, steel hardenability, and severity of quench. 一种表面硬化工艺，在该工艺中，合适的钢工件在加热和淬火硬化后，会形成一层马氏体层或壳，该层或壳紧随工件的轮廓，并包围一个基本上为珠光体相变产物的核心。这一结果通过截面尺寸、钢淬透性和淬火强度之间的适当平衡来实现。 |
| Fillister head | 槽头 |
Similar to a pan head but with a smaller head diameter and a taller head, with higher vertical sides. 类似于盘头，但头部直径较小，头部较高，垂直边较高。 |
| Fastener quality | 紧固件质量 |
A fastener’s adherence to its specification for dimensional tolerances, mechanical properties, and other requirements stated under applicable standards. 紧固件对尺寸公差、机械性能和适用标准规定的其他要求的规范的遵守情况。 |
| 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。 |
| Crack-extension resistance (KR) | 抗裂扩展性（KR） |
A measure of the resistance of a material to crack extension, expressed in terms of the stress-intensity factor, the crack-extension force, or values of Jderived using the J-integral concept. 材料对裂纹扩展的抵抗力的量度，以应力强度因子、裂纹扩展力或使用J积分概念导出的J值表示。 |
| Ideal crack | 理想裂缝 |
A simplified model of a crack used in elastic-stress analysis. In a stress-free body, the crack has two smooth surfaces that are coincident and join within the body along a smooth curve called the crack front; in two-dimensional representations, the crack front is called the crack tip. 用于弹性应力分析的裂纹简化模型。在无应力物体中，裂纹有两个光滑表面，它们在物体内沿称为裂纹前缘的平滑曲线重合并连接；在二维表示中，裂纹前缘称为裂纹尖端。 |
| 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。 |
| 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。 |
| 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。 |
| Turbocharging | 涡轮增压 |
A method of supercharging in which the hot exhaust gas from a piston engine is used to drive a turbine which powers the supercharging compressor. A turbocharger is the turbine/compressor combination. The compressor is usually of radial outflow design while radial, axial, and mixed-flow turbines are all in use. The wastegate is a valve that reduces the flow of exhaust gas into the turbine to limit the boost produced or overspeeding. Not shown in the diagram are bearings, oil passages, etc. 一种增压方法，其中活塞发动机的热废气用于驱动涡轮，涡轮为增压压缩机提供动力。涡轮增压器是涡轮/压缩机组合。压缩机通常为径向流出设计，而径向、轴向和混流式涡轮机都在使用。废气旁通阀是一种减少进入涡轮的废气流量以限制产生的增压或超速的阀。 |
| Fracture mechanics | 断裂力学 |
The stress analysis of bodies containing cracks. The use of stressconcentration factors and other correction factors of traditional strength of materials is inadequate when flaws are present initially (or develop during loading), since fracture depends not only on stress but also the size of the crack. Traditional strength of materials stress calculations cannot predict either the safe working stress in the presence of a known flaw, or the critical size of flaw just tolerable with a given working stress. 含裂纹物体的应力分析。当初始存在缺陷（或在加载过程中形成缺陷）时，使用应力集中系数和传统材料强度的其他修正系数是不够的，因为断裂不仅取决于应力，还取决于裂纹的大小。传统的材料强度应力计算既不能预测已知缺陷存在时的安全工作应力，也不能预测给定工作应力下可容忍的缺陷临界尺寸。 |
| 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。 |
| Rockwell hardness test | 洛氏硬度测试 |
An indentation-hardness test using a calibrated machine that utilizes the depth of indentation, under constant load, as a measure of hardness. A direct-reading hardness test based on depth of indentation, in which a minor load (typically 30 to 100 N) is applied before the major load (typically 120 to 1 500 N). There are different scales using conical or spherical indenters for different ranges of hardness. An indentation hardness test based on the depth of penetration of a specified penetrator into the specimen under certain arbitrarily fixed conditions. 使用校准机器进行的压痕硬度测试，该机器利用恒定载荷下的压痕深度作为硬度测量值。一种基于压痕深度的直读硬度测试，其中在主要载荷（通常为120至1500N）之前施加较小载荷（通常是30至100N）。对于不同的硬度范围，使用锥形或球形压头有不同的刻度。在某些任意固定条件下，基于指定穿透器穿透试样深度的压痕硬度试验。 |
| 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。 |
| Congruent transformation | 全等变换 |
An isothermal or isobaric phase change in which both of the phases concerned have the same composition throughout the process. 等温或等压相变，其中相关的两个相在整个过程中具有相同的成分。 |
| 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。 |
| Statistic | 统计 |
A summary value calculated from the observed values in a sample. 根据样本中的观察值计算得出的汇总值。 |
| 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。 |
| Structural-integrity analysis | 结构完整性分析 |
Assessment of components and structures for likelihood of failure by buckling, fracture, yielding, etc. under conditions of normal and accident loading. 在正常和事故荷载条件下，评估部件和结构因屈曲、断裂、屈服等而失效的可能性。 |
| 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。 |
| Rivet | 铆钉 |
A short rod with a head on one end that is inserted through aligned holes in plates to be joined, after which a second head is made on the protruding shank by hammering or forming. The most common head shapes are flat, domed, and inverse conical. In an array, the rivet pitch is the distance between the centres of adjacent rivets. Failure may occur by different mechanisms or modes. A one piece fastener consisting of a head and a body and used for fastening two or more pieces together by passing the body through a hole in each piece and then forming a second head on the body end. It cannot be removed except by taking off the head. 一种一端有头的短杆，插入待连接板上对齐的孔中，然后通过锤击或成型在突出的杆身上制作第二个头。最常见的头部形状是扁平、圆顶和倒锥形。在阵列中，铆钉间距是相邻铆钉中心之间的距离。故障可能由不同的机制或模式发生。一种一体式紧固件，由头部和主体组成，用于将两个或多个部件紧固在一起，方法是将主体穿过每个部件上的孔，然后在主体端部形成第二个头部。除非取下头部，否则无法移除。 |
| Half nut | 半螺母 |
A mechanism attached to the apron of a lathe and operated by a lever. The lever opens and closes a nut that has been split lengthwise so that the two halves of the nut can be closed upon the lead screw when threads are being cut. Also called Split Nut. 固定在车床裙板上并由杠杆操作的机械装置，杠杆打开和关闭纵向分开的螺母，以便在切割螺纹时，螺母的两半可以在丝杠上闭合。也称为剖分螺母。 |
| 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。 |
| Absolute stability | 绝对稳定 |
Condtion of a linear system in which there exists a limiting value of the open-loop gain such that the system is stable for all lower values of that gain, and unstable for all higher values. 线性系统的条件，其中存在开环增益的限制值，使得系统对于该增益的所有较低值都是稳定的，而对于所有较高值来说都是不稳定的。 |
| Cheese head | 圆柱头 |
A cylindrical head on a screw or bolt. For driving, it may be slotted, or hexagonally recessed. 螺钉或螺栓上的圆柱头。为了驱动，它可以是开槽的，也可以是六角形的。 |
| Shear modulus (G) | 剪切模量（G） |
The ratio of shear stress to the corresponding shear strain for shear stresses below the proportional limit of the material. Values of shear modulus are usually determined by torsion testing. Also known as modulus of rigidity. 对于低于材料比例极限的剪切应力，剪切应力与相应剪切应变之比。剪切模量值通常通过扭转试验确定。也称为刚度模量。 |
| Impact wrench | 冲击扳手 |
An air- or electric-powered wrench in which multiple blows from tiny hammers are used to produce output torque to tighten fasteners. A pneumatically-or electrically-powered socket wrench used to tighten or loosen nuts through the application of torque in a rapid series of impulses. 一种气动或电动扳手，使用小锤子多次敲击来产生输出扭矩以拧紧紧固件，用于通过在一系列快速脉冲中施加扭矩来拧紧或松开螺母。 |
| 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。 |
| Stress equalizing | 应力均衡 |
A low-temperature heat treatment used to balance stresses in cold-worked material without an appreciable decrease in the mechanical strength produced by cold working. 一种低温热处理，用于平衡冷加工材料中的应力，而不会明显降低冷加工产生的机械强度。 |
| Pressure loss (Unit Pa) | 压力损失（单位Pa） |
The loss in stagnation pressure in internal flow due to wall friction and minor losses in fittings. 壁面摩擦引起的内部流动停滞压力损失和配件的微小损失。 |
| 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。 |
| Radiator | 散热器 |
A heat exchanger used to transfer thermal energy from one fluid to another for heating or cooling purposes. Despite the name, the principal mode of heat transfer is convection rather than radiation. In motor vehicles, water circulated through the engine block is cooled as it flows through the tubes of an air-cooled heat exchanger. In domestic radiators, hot water from a boiler is circulated through a heat exchanger with a large surface area which transfers heat to the surrounding air. 一种热交换器，用于将热能从一种流体传递到另一种流体，用于加热或冷却。尽管有这个名字，但热传递的主要方式是对流而不是辐射。在机动车辆中，通过发动机缸体循环的水在流经风冷热交换器的管道时被冷却。在家用散热器中，来自锅炉的热水通过具有大表面积的热交换器循环，该热交换器将热量传递给周围的空气。 |
| Absorber | 吸收器 |
1. An auxiliary vibratory system that favourably modifies the vibration characteristics of a main system. 2. Part of an absorption refrigeration system in which the refrigerant is absorbed by a transport medium. 3. The absorber plate is the receiver of a concentrating solar collector where the radiation is absorbed. 1.一种辅助振动系统，可有利地改变主系统的振动特性。2.吸收式制冷系统的一部分，其中制冷剂被传输介质吸收。3.吸收板是吸收辐射的聚光太阳能集热器的接收器。 |
| 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。 |
| Surface hardening | 表面硬化 |
A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred. 一个通用术语，涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。 |
| 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。 |
| Actuating system | 驱动系统 |
A system in which an electrical, pneumatic or hydraulic input supplied to an actuator produces force, torque, or displacement, usually in a controlled way. 一种系统，其中提供给执行器的电气、气动或液压输入通常以受控方式产生力、扭矩或位移。 |
| 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。 |
| Closed system | 封闭系统 |
A closed thermodynamic system consists of a fixed amount of mass. No mass can cross its boundary although energy can, in the form of work or heat, and its volume can change. 一个封闭的热力学系统由一定量的质量组成。能量可以以功或热的形式存在，其体积可以改变，但没有质量可以越过它的边界。 |
| 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。 |
| Scratching | 刮擦 |
In tribology, the mechanical removal or displacement, or both, of material from a surface by the action of abrasive particles or protuberances sliding across the surfaces. 在摩擦学中，通过在表面上滑动的磨粒或突起的作用，材料从表面上的机械移除或移位，或两者兼而有之。 |
| Compressive stress (Unit Pa) | 压缩应力（单位Pa） |
The compressive load per unit area at a point in a component. 部件中某点的每单位面积的压缩载荷。 |
| 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。 |
| 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。 |
| Heat-treatable alloy | 可热处理合金 |
An alloy that can be hardened by heat treatment. 一种可以通过热处理硬化的合金。 |
| Condensing boiler | 冷凝锅炉 |
A relatively small industrial or domestic boiler that burns sulfur-free natural gas so that the products of combustion do not contain sulfuric acid and can be allowed to condense on heat-transfer surfaces without danger of corrosion. 一种相对较小的工业或家用锅炉，燃烧无硫天然气，因此燃烧产物不含硫酸，并且可以在传热表面上冷凝而没有腐蚀的危险。 |
| 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。 |
| 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。 |
| Torque motor | 力矩电机 |
A type of induction motor that can apply a steady torque even when prevented from rotating. 一种感应电动机，即使被阻止旋转也能施加稳定的转矩。 |
| Oldham coupling | 十字联轴节 |
(double-slider coupling) A device for connecting a pair of misaligned parallel shafts, on the end of each of which are flanges having diametral tenons (tongues) that engage with matching slots spaced at 90° in an intermediate disc. As the coupling rotates, the disc compensates for shaft offset by sliding along each tenon in turn. Low-friction surfaces are requisite and the disc is often made of a polymer. An alternative arrangement has the slots in the flanges and the tenons on the disc. （双滑块联轴器）一种连接一对未对准平行轴的装置，在每个平行轴的端部有法兰，法兰具有直径榫（舌），与中间盘中间隔90°的匹配槽接合。当联轴器旋转时，圆盘通过依次沿每个榫头滑动来补偿轴偏移。低摩擦表面是必需的，阀盘通常由聚合物制成。另一种布置方式是法兰上的槽和阀盘上的榫头。 |
| Kilo (k) | 千（k） |
An SI unit prefix indicating a multiplier of 103; thus kilometre (km) is a unit of length equal to one thousand metres. 表示乘法器103的SI单位前缀；1千米是长度单位，等于1000米。 |
| Balance piston | 平衡活塞 |
(balance drum, dummy piston) A disc attached to the shaft of a turbine or compressor, to one side of which high or low pressure is applied to counteract the axial thrust produced by the pressure change across the machine. A form of thrust bearing. （平衡鼓，假活塞）连接在涡轮机或压缩机轴上的圆盘，在其一侧施加高压或低压，以抵消机器压力变化产生的轴向推力。推力轴承的一种形式。 |
| 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。 |
| 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。 |
| Ideal gas laws | 理想气体定律 |
The law relating pressure, temperature and volume of an ideal (perfect) gas pV = mRT, where R is the gas constant. The law implies that at constant temperature T, the product of pressure p and volume V is constant (Boyle’s law), and at constant pressure, the volume is proportional to the temperature (Charles’ law). 与理想（完美）气体的压力、温度和体积相关的定律pV=mRT，其中R是气体常数。该定律意味着在恒定温度T下，压力p和体积V的乘积是恒定的（波义耳定律），而在恒定压力下，体积与温度成正比（查尔斯定律）。 |
| 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。 |
| 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。 |
| Fracture surface | 断裂面 |
The irregular surface produced when a piece of metal is broken. 一块金属破碎时产生的不规则表面。 |
| Torr | 托尔 |
A non-SI unit of pressure commonly used in vacuum systems; defined by 760 torr = 1 atm so that 1 torr = 133.322 368 4 Pa, and approximately equivalent to the pressure corresponding to 1 mm of mercury. 真空系统中常用的非SI压力单位；由760托=1大气压定义，因此1托=133.3223684帕，近似等于对应于1毫米汞柱的压力。 |
| 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。 |
| Fatigue life for p % survival | p%存活率的疲劳寿命 |
An estimate of the fatigue life that p% of the population would attain or exceed at a given stress level. The observed value of the median fatigue life estimates the fatigue life for 50% survival. Fatigue life for p% survival values, where p is any number, such as 95, 90, etc., may also be estimated from the individual fatigue life values. p%存活在给定应力水平下达到或超过的疲劳寿命估计值。中值疲劳寿命的观察值估计了50%存活率的疲劳寿命。p%存活值的疲劳寿命，其中p为任何数字，如95、90等，也可根据单个疲劳寿命值进行估算。 |
| Cleavage | 分裂 |
The tendency of a material to cleave or split along definite crystallographic planes. 材料沿特定晶面劈裂或分裂的趋势。 |
| 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。 |
| 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。 |
| Torque wrench | 扭矩扳手 |
A manual wrench which incorporates a gage or measuring apparatus of some sort to measure and display the amount of torque being delivered to the nut or bolt. All wrenches produce torque. Only a torque wrench tells how much torque. A socket wrench or ring spanner that can be set to allow a specific torque to be applied to a nut or bolt head. 一种手动扳手，包括某种量规或测量装置，用于测量和显示传递至螺母或螺栓的扭矩量。所有扳手都产生扭矩。只有扭矩扳手才能显示扭矩大小。一种套筒扳手或梅花扳手，可设置为允许对螺母或螺栓头施加特定扭矩。 |
| Continuous precipitation | 连续沉淀 |
Precipitation from a supersaturated solid solution in which the precipitate particles grow by longrange diffusion without recrystallization of the matrix. Continuous precipitates grow from nuclei distributed more or less uniformly throughout the matrix. They usually are randomly oriented, but may form a Widmanstätten structure. 来自过饱和固溶体的沉淀，其中沉淀颗粒通过长程扩散生长而无需基质再结晶。连续析出物从在整个基体中或多或少均匀分布的核生长而来。它们通常是随机取向的，但可能形成魏氏结构。 |
| Temperature factor | 温度系数 |
A calibration constant used in ultrasonic measurement of bolt stress or strain. Accounts for the effects of thermal expansion and the temperature-induced change in the velocity of sound. 用于螺栓应力或应变超声波测量的校准常数。说明了热膨胀和温度引起的声速变化的影响。 |
| Caterpillar | 毛虫式履带 |
(crawler vehicle) A vehicle that ‘lays its own road’ by running on endless belts, driven by toothed wheels, on each side. Used on soft ground where spreading of the load reduces contact stress. （履带式车辆）通过在每一侧由齿轮驱动的环形皮带运行来“铺设自己的道路”的车辆。用于负载分散可减少接触应力的松软地面。 |
| Barrier protection | 屏障保护 |
The coating on a fastener is said to provide barrier protection if it merely isolates the fastener from the environment. Paint, for example, provides barrier protection. 如果仅将紧固件与环境隔离，则据说紧固件上的涂层可提供屏障保护。例如，油漆提供屏障保护。 |
| Screw pump | 螺杆泵 |
A positive-displacement pump that uses one or more helical rotors rotating within a casing to transfer liquids or slurries. 一种容积式泵，使用一个或多个在外壳内旋转的螺旋转子输送液体或泥浆。 |
| Full size body | 全尺寸螺纹杆 |
The body of a bolt or screw which has a diameter between the minimum and maximum limits of the major diameter of the thread. 螺栓或螺钉的主体，其直径介于螺纹大径的最小和最大限制之间。 |
| Plane-strain fracture toughness (KIc) | 平面应变断裂韧性（KIc） |
The crack extension resistance under conditions of crack-tip plane strain. 裂纹尖端平面应变条件下的裂纹扩展阻力。 |
| Embrittlement | 脆化 |
The loss of ductility or fracture toughness of materials, either during processing or in service. The severe loss of ductility or toughness or both, of a material, usually a metal or alloy. Many forms of embrittlement can lead to brittle fracture. Many forms can occur during thermal treatment or elevated-temperature service (thermally induced embrittlement). Some of these forms of embrittlement, which affect steels, include blue brittleness, 885 °F (475 °C) embrittlement, quench-age embrittlement, sigma-phase embrittlement, strain-age embrittlement, temper embrittlement, tempered martensite embrittlement, and thermal embrittlement. In addition, steels and other metals and alloys can be embrittled by environmental conditions (environmentally assisted embrittlement). The forms of environmental embrittlement include acid embrittlement, caustic embrittlement, corrosion embrittlement, creep-rupture embrittlement, hydrogen embrittlement, liquid metal embrittlement, neutron embrittlement, solder embrittlement, solid metal embrittlement, and stress-corrosion cracking. 材料在加工或使用过程中的延展性或断裂韧性损失。通常是金属或合金的延展性或韧性或两者的严重损失。多种形式的脆化可导致脆性断裂。在热处理或高温服务期间，可能会出现多种形式（热致脆化）。影响钢的一些脆化形式包括蓝脆、885°F（475°C）脆化、淬火时效脆化、西格玛相脆化、应变时效脆化，回火脆化、回火马氏体脆化和热脆化。此外，钢和其他金属和合金可能因环境条件而脆化（环境辅助脆化）。环境脆化的形式包括酸脆化、碱脆化、腐蚀脆化、蠕变断裂脆化、氢脆化、液态金属脆化、中子脆化、焊料脆化、固态金属脆化和应力腐蚀开裂。 |
| Lüders lines | 吕德斯线 |
Elongated surface markings or depressions, often visible with the unaided eye, that form along the length of sheet metal or a tension specimen at an angle of approximately 45° to the loading axis. Caused by localized plastic deformation, they result from discontinuous (inhomogeneous) yielding. Also known as Lüders bands, Hartmann lines, Piobert lines, or stretcher strains. 拉长的表面标记或凹陷，通常肉眼可见，沿金属板或拉伸试样的长度形成，与加载轴的角度约为45°。由于局部塑性变形，它们是不连续（不均匀）屈服的结果。也被称为吕德斯带、哈特曼线、皮奥伯特线或拉伸线。 |
| Self-loosening | 自松动 |
The process by which a supposedly tightened fastener becomes loose, as a result of vibration, thermal cycles, shock, or anything else which cause transverse slip between joint members and between male and female threads. Vibration loosening is a common, but special, case of self-loosening. 由于振动、热循环、冲击或任何其他导致接头构件之间以及阳螺纹和阴螺纹之间横向滑动的原因，紧固件松动的过程。振动松动是自松动的一种常见但特殊的情况。 |
| Pitting | 点蚀 |
In tribology, a type of wear characterized by the presence of small, sharp surface cavities formed by processes such as fatigue, local adhesion, wear, corrosion, or cavitation. 在摩擦学中的一种磨损，其特征是存在由疲劳、局部粘附、磨损、腐蚀或空穴等过程形成的小而尖锐的表面空穴。 |
| 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。 |
| 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。 |
| Universal joint (Hooke’s joint) | 万向节（胡克接头） |
A double-pivoted connection that allows power and torque to be transmitted between two shafts at an angle to each other. For constant driving angular velocity of the input yoke, the angular velocity of the output yoke fluctuates by amounts depending on the angle of intersection of the shafts. Speeds of the driving and driven shafts may be made identical (giving a constant-velocity joint) when an intermediate shaft, at each end of which there is a universal joint, is interposed. The driving and driven shafts must be equally inclined to the intermediate shaft, the two forks of which must lie in the same plane. 一种双枢轴连接，允许动力和扭矩以一定角度在两个轴之间传递。对于输入磁轭的恒定驱动角速度，输出磁轭的角速度根据轴的相交角度波动。当插入中间轴时，驱动轴和从动轴的速度可以相同（提供恒定速度接头），中间轴的两端都有万向节。主动轴和从动轴必须与中间轴倾斜相等，中间轴的两个叉必须位于同一平面内。 |
| 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。 |
| Mohr–Coulomb yield criterion | Mohr–Coulomb屈服准则 |
A pressure-dependent yield criterion, according to which yielding occurs when the stress at a point in a material falls on the envelope created by the Mohr’s stress circles at yielding for various tests such as tension, shear, and compression that have different components of hydrostatic stress. 一种与压力相关的屈服准则，根据该准则，当材料中某一点的应力落在屈服时的莫尔应力圆所形成的包络线上时，即发生屈服，用于各种试验，如具有不同静水应力分量的拉伸、剪切和压缩。 |
| Variance | 方差 |
A measure of the squared dispersion of observed values or measurements expressed as a function of the sum of the squared deviations from the population mean or sample average. 观测值或测量值的平方离散度的度量，表示为总体平均值或样本平均值的平方偏差之和的函数。 |
| 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。 |
| Unit | 单位 |
A numerical indication of the magnitude of a physical quantity. The basic units of mass, length, time, etc. are relative to agreed standards. 物理量大小的数字指示。质量、长度、时间等基本单位与商定的标准相对应。 |
| Yield stress | 屈服应力 |
The stress level of highly ductile materials, such as structural steels, at which large strains take place without further increase in stress. 高韧性材料（如结构钢）的应力水平，在该应力水平下发生大应变而不会进一步增加。 |
| 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。 |
| Following flank | 跟随侧翼 |
The flank of a thread opposite to the leading flank. 与前牙面相对的螺纹牙面。 |
| 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。 |
| Anisotropy | 各向异性 |
The characteristic of exhibiting different values of a property in different directions with respect to a fixed reference system in the material. 相对于材料中的固定参考系统，在不同方向上表现出不同属性值的特性。 |
| Hot quenching | 热淬火 |
An imprecise term used to cover a variety of quenching procedures in which a quenching medium is maintained at a prescribed temperature above 70 °C (160 °F) 一个不精确的术语，用于涵盖各种淬火程序，其中淬火介质规定温度保持在70°C（160°F）以上。 |
| Feather key | 滑键 |
A parallel key fastened in either the shaft or in the hub of a member sliding on it. When fastened in the shaft, it must be long enough to hold or drive the sliding member in any of its positions on the shaft. When in the sliding member the key need only be as long as the hub. 一种平行键，固定在轴上或在其上滑动的构件的轮毂上。当固定在轴上时，其长度必须足以将滑动构件固定或驱动在轴上的任何位置。当处于滑动构件中时，键只需与轮毂一样长。 |
| 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。 |
| Preload | 预载 |
The tension created in a threaded fastener when the nut is first tightened. Often used interchangeably, but incorrectly, with Working load or bolt force or bolt tension 第一次拧紧螺母时螺纹紧固件中产生的张力。经常与工作载荷或螺栓力或螺栓张力互换使用但容易使用不当。 |
| Verification | 检验 |
Checking or testing an instrument to ensure conformance with a specification. 检查或测试仪器以确保符合规范。 |
| Liquid nitriding | 液体氮化 |
A method of surface hardening in which molten nitrogen-bearing, fused-salt baths containing both cyanides and cyanates are exposed to parts at subcritical temperatures. 一种表面硬化方法，其中含有氰化物和氰酸盐的熔融含氮熔盐浴在亚临界温度下暴露于零件。 |
| Toothed gearing | 齿轮传动 |
In principle, friction between circular discs in tangential contact could be used to transmit rotation and power between shafts, but the power level would be very limited and the velocity ratio affected by slip. To make the drive positive, gear wheels are used instead in which teeth extend above and below the diameters (the pitch-circle diameters) of discs in ideal rolling contact. The diagram shows the nomenclature for spur gears, the simplest type of gearing between parallel shafts, which are cylindrical in shape with straight teeth parallel to the axis of rotation. 原则上，切向接触的圆盘之间的摩擦可用于在轴之间传递旋转和动力，但动力水平非常有限，速比受滑动的影响。为了使驱动积极，使用齿轮代替，齿轮中的齿延伸到理想滚动接触的圆盘直径（节圆直径）的上方和下方。该图显示了直齿轮的名称，这是平行轴之间最简单的齿轮传动类型，其形状为圆柱形，直齿平行于旋转轴。 |
| constitutive equation | 本构方程 |
(constitutive relation) 1. In solid mechanics or fluid mechanics, an algebraic or numerical relation for the dependency of stress on deformation, strain, strain rate, temperature, etc. in a material. In solid mechanics such a relation is sometimes called an equation of state. Simple linear examples include Hooke’s law and Newton’s viscosity law. 2. In heat transfer, a relation, such as Fourier’s law of heat conduction, connecting heat flux with temperature gradient. （本构关系）1.在固体力学或流体力学中，应力与材料的变形、应变、应变率、温度等之间的代数或数值关系。在固体力学中，这种关系有时称为状态方程。简单的线性例子包括胡克定律和牛顿粘度定律。2.在传热学中，将热流与温度梯度联系起来的一种关系，如傅立叶热传导定律。 |
| Terminal velocity (Unit m/s) | 终端速度（单位：m/s） |
The velocity reached by an object in free fall through a fluid when the upward drag and buoyancy forces just balance the object’s weight. For an object with a density lower than that of the fluid, the terminal velocity is vertically upwards. 当向上的阻力和浮力正好平衡物体的重量时，物体自由下落通过流体达到的速度。对于密度低于流体密度的物体，终端速度垂直向上。 |
| Thermal stresses | 热应力 |
Stresses in metal resulting from nonuniform temperature distribution. 由不均匀温度分布引起的金属应力。 |
| Nut factor | 螺母系数 |
An experimental constant used to evaluate or describe the ratio between the torque applied to a fastener and the Preload achieved as a result. 用于评估或描述施加在紧固件上的扭矩与由此获得的预载之间的比率的实验常数。 |
| Forging cracks | 锻造裂纹 |
This may occur during fastener manufacturing at the cutting or forging operations and are located on the top of the head or on the raised periphery of indented head bolts. 这可能发生在紧固件制造过程中的切削或锻造操作中，并且位于头部的顶部或带锯齿的头部螺栓的凸起周边上。 |
| Tensioner | 张紧器 |
A hydraulic tool used to tighten a fastener by stretching it rather than by applying a substantial torque to the nut. After the tension has stretched the bolt or stud, the nut is run down against the joint with a modest torque, and the tensioner is disengaged from the fastener. The nut holds the stretch produced by the tensioner. 一种液压工具，用于通过拉伸紧固件而不是对螺母施加较大扭矩来拧紧紧固件。张力拉伸螺栓或螺柱后，以适当的扭矩将螺母向下压靠接头，张紧器与紧固件分离。螺母保持张紧器产生的拉伸。 |
| Maximum-and-minimum thermometer | 最高和最低温度计 |
(minimum-maximum thermometer, Six’s thermometer) A liquid-in-glass instrument designed to register the maximum and minimum temperatures experienced over a given time period. （最低-最高温度计，Six's温度计）一种液体玻璃仪器，用于记录给定时间段内经历的最高和最低温度。 |
| Densimeter | 密度计 |
An instrument used to determine the density or relative density of a solid or liquid. 用于测定固体或液体的密度或相对密度的仪器。 |
| 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。 |
| Vacuum pump | 真空泵 |
A pump for exhausting air and non-condensable gases from a vessel to be maintained at sub-atmospheric pressure. The pirani and thermal-conductivity gauges are vacuum gauges used to measure the absolute pressure within a vacuum system (vacuum level), usually expressed in torr or Pa. 用于从容器中排出空气和不凝性气体以保持在亚大气压的泵。皮拉尼和热导率计是用于测量真空系统内绝对压力（真空水平）的真空计，通常用托或帕表示。 |
| 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。 |
| International Bureau of Weights and Measures | 国际度量衡局IBWM |
(BIPM, Bureau International des Poids et Mesures) The intergovernmental organization which has the mandate to provide the basis for a single, coherent system of measurements, traceable to the International System of Units. （BIPM，国际计量局）政府间组织，其任务是为可追溯到国际单位制的单一、一致的计量系统提供基础。 |
| Carbon restoration | 碳修复 |
Replacing the carbon lost in the surface layer from previous processing by carburizing this layer to substantially the original carbon level. Sometimes called recarburizing. 通过将该层渗碳到基本上原始的碳水平来替换先前处理中在表面层中损失的碳。有时称为再碳化。 |
| 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。 |
| U-bend | U形管 |
U-bend A 180° bend in a pipe. 180°弯曲的管道。 |
| Vent | 发泄 |
A small valve that allows the release of pressurized fluid from a pipe, pressure vessel, etc., often to the atmosphere. 一种小阀门，允许将加压流体从管道、压力容器等中释放到大气中。 |
| 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。 |
| 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。 |
| Stove bolt | 炉用螺栓 |
This bolt has been so named because of its use in stove building. It is made in a number of different forms, either with a round button, or flat countersunk head, the head having a slot for a screwdriver and the threaded end being provided with a square or hexagon nut. 这种螺栓因其在炉灶建筑中的用途而得名。它有多种不同的形式，有圆形按钮或平沉头，头部有螺丝刀槽，螺纹端有方形或六角螺母。 |
| Embedment | 嵌入 |
Localized plastic deformation in heavily loaded fasteners allows one part to sink into, or smooth the surface of, a softer or more heavily loaded second part. Nuts embed themselves in joint surfaces. Bolt threads embed themselves in nut threads, etc. 重载紧固件中的局部塑性变形允许一个零件陷入较软或更重载的第二零件中，或使其表面光滑。螺母嵌入接合面中。例如螺栓螺纹嵌入螺母螺纹等。 |
| 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。 |
| Reduction in area (RA) | 缩小面积（RA） |
The difference between the original cross-sectional area of a tensile specimen and the smallest area at or after fracture as specified for the material undergoing testing. Also known as reduction of area. 拉伸试样的原始横截面积与试验材料断裂时或断裂后的最小面积之间的差值，也称为减少面积。 |
| Controlled cooling | 控制冷却 |
Cooling from an elevated temperature in a predetermined manner, to avoid hardening, cracking, or internal damage, or to produce desired microstructure or mechanical properties. 以预定方式从升高的温度冷却，以避免硬化、开裂或内部损坏，或产生所需的微观结构或机械性能。 |
| Turbine blades (turbine buckets) | 涡轮叶片 |
1. The aerofoil-shaped vanes that form the rotor and stator of a gas, steam or hydraulic turbine. 2. The cup-shaped vanes of a Pelton wheel. 1.形成燃气、蒸汽或水力涡轮机的转子和定子的翼型叶片。2.冲击轮的杯形叶片。 |
| 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。 |
| 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。 |
| Degradation of energy | 能源退化 |
Conversion of energy into forms of lower usefulness due to irreversibilities in energy transfer and conversion processes. The increase in entropy can be regarded as a measure of the degradation of energy. 由于能量转移和转换过程中的不可逆性，将能量转换为低效形式。熵的增加可以看作是能量退化的量度。 |
| 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）。 |
| Abrasivity | 磨蚀性 |
The extent to which a surface, particle, or collection of particles will tend to cause abrasive wear when forced against a solid surface under relative motion and under prescribed conditions. 在相对运动和规定条件下，一个表面、颗粒或颗粒集合在被迫抵靠固体表面时趋向于引起磨粒磨损的程度。 |
| Freezing point | 冰点 |
The temperature at which a substance changes phase (or state) from liquid to solid. The freezing point for most substances increases as pressure increases. The reverse process, from solid to liquid, is melting; melting point is the same as freezing point. 物质从液态变为固态的温度。大多数物质的冰点随着压力的增加而增加。从固体到液体的逆过程是熔化；熔点与凝固点相同。 |
| Carbon steels | 碳钢 |
(plain carbon steels) Steels in which carbon is the principal alloying element, and the amount of manganese does not exceed 1.65% and the copper and silicon contents are less than 0.60%. There are three main types: low-carbon steels (0.08–0.35% carbon); medium-carbon steels (0.35–0.50% carbon); and high-carbon steels (0.50–2.0% carbon). （普通碳钢）以碳为主要合金元素，锰含量不超过1.65%，铜和硅含量低于0.60%的钢。主要有三种类型：低碳钢（0.08-0.35%碳）；中碳钢（0.35–0.50%碳）；和高碳钢（0.50–2.0%碳）。 |
| 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。 |
| Axial load (Unit N) | 轴向载荷（单位N） |
In general, a tensile or compressive load directed along the axis of a component. Strictly the load should pass through the centroid of the cross section to avoid inducing bending moments and be perpendicular to the plane of the section. 通常，沿部件的轴定向的拉伸或压缩载荷。严格来说，载荷应通过横截面的质心以避免产生弯矩并垂直于横截面。 |
| Mole (mol) | 摩尔（mol） |
The base unit of the amount of substance in the SI system. It was previously defined as the amount of substance of a system that contains as many elementary entities as there are atoms in 0.012 kg of carbon-12. From 20 May 2019 it has been defined as the amount of substance containing exactly 6.022 140 76 × 1023 elementary entities. SI国际单位制中物质量的基本单位。此前，它被定义为一个系统中的物质量，该系统包含的基本实体数量与0.012千克碳-12中的原子数量相同。从2019年5月20日起，它已被定义为包含6.02214076×1023个基本实体的物质量。 |
| Jack | 杰克装置 |
A lifting device that exerts large forces over small displacements, achieved by mechanical gearing or hydraulics. 通过机械传动或液压装置在小位移上施加大力的提升装置。 |
| Kelvin (K) | 开尔文（K） |
The SI unit of temperature. The Kelvin temperature scale has a zero point at absolute zero and degree intervals (kelvins) the same size as degrees Celsius. The freezing point of water occurs at 273K (0ºC) and the boiling point at 373 K (100ºC). The base unit of thermodynamic temperature in the SI system. It was previously defined to be the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. From 20 May 2019 it has been defined by taking the fixed numerical value of the Boltzmann constant kB to be 1.380 649 × 10−23 when expressed in the unit J/K, which is equal to kg.m²/(s²K). 国际单位制中热力学温度的基本单位。开尔文温度标度在绝对零度和与摄氏度大小相同的度间隔（开尔文）处有一个零点。水的冰点为273K（0ºC），沸点为373K（100ºC）。它先前被定义为水三相点热力学温度的分数1/273.16。从2019年5月20日起，通过将玻尔兹曼常数kB的固定数值取为1.380649×10来定义−当以等于kg·m²/（s²K）的单位J/K表示时。 |
| Compression | 压缩 |
1. Loading, the principal effect of which is to squeeze and shorten a component or testpiece. 2. The reduction in volume and increase in density of a substance as a consequence of increased pressure. 1.加载，其主要作用是挤压和缩短部件或试件。2.压力增加导致物质体积减少和密度增加。 |
| 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。 |
| Toughening mechanisms | 增韧机理 |
Various methods of increasing the resistance to crack initiation and propagation in materials. They include transformation toughening, in which the microstructure around the crack tip alters so as to slow down or arrest cracks; deflexion of cracks; various ways of de-sharpening crack tips; fibre bridging of cracks; and fibre pull-out. 增加材料中裂纹萌生和扩展阻力的各种方法。它们包括相变增韧，其中裂纹尖端周围的微观结构发生变化，以减缓或阻止裂纹；裂纹偏转；消除裂纹尖端锐化的各种方法；纤维桥接裂纹；和纤维拉出。 |
| 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。 |
| Recrystallization annealing | 再结晶退火 |
Annealing cold-worked metal to produce a new grain structure without phase change. 退火冷加工金属以产生新的晶粒结构而不发生相变。 |
| Fastener with waisted shank | 带腰柄的紧固件 |
Finished fastener with a shank diameter of ds < d2. 柄径ds |
| 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。 |
| Graphitic carbon | 石墨碳 |
Free carbon in steel or cast iron. 钢或铸铁中的游离碳。 |
| 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。 |
| 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。 |
| Silky fracture | 丝状断口 |
A metal fracture in which the broken metal surface has a fine texture, usually dull in appearance. Characteristic of tough and strong metals. 一种金属断裂，断裂的金属表面具有精细的纹理，通常外观暗淡。具有坚韧和坚固金属的特征。 |
| 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。 |
| 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。 |
| Initial strain | 初始应变 |
The strain in a specimen immediately upon achieving the given loading conditions in a creep test (before creep occurs). Sometimes referred to as instantaneous strain. 在蠕变试验中（蠕变发生之前）达到给定载荷条件后，试样立即产生的应变。有时称为瞬时应变。 |
| 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。 |
| 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。 |
| Calorie | 卡路里 |
(cal, gram calorie, small calorie) An obsolete (i.e. non-SI) unit of energy equal to 4.186 8 J. It is the amount of energy needed to raise the temperature of 1 gram of pure airfree water from 14.5°C to 15.5°C at standard atmospheric pressure. （卡，克热量，小热量）一种已被淘汰的（即非SI）能量单位，等于4.1868J。它是在标准大气压力下将1克纯无空气水的温度从14.5℃升高到15.5℃所需的能量。 |
| 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。 |
| 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。 |
| 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。 |
| Transmission | 传输 |
The system that transmits power and torque from a power source; for example a shaft, belts and pulleys, or a gear train. In the case of a motor vehicle, it includes the gearbox, clutch, propeller shaft, differential and final drive shafts. 从动力源传输功率和扭矩的系统；例如轴、皮带和滑轮或齿轮系。对于机动车辆，包括变速箱、离合器、传动轴、差速器和终传动轴。 |
| Ausforming | 形变热处理 |
Thermomechanical treatment of steel in the metastable austenitic condition below the recrystallization temperature followed by quenching to obtain martensite and/or bainite. 在低于再结晶温度的亚稳态奥氏体条件下对钢进行热机械处理，然后淬火以获得马氏体和/或贝氏体。 |
| Density | 密度 |
The mass per unit volume of a solid material. (mass density, ρ) (Unit kg/m³) The mass per unit volume of a substance that satisfies the continuum assumption. The reciprocal of specific volume. 固体材料每单位体积的质量。（质量密度，ρ）（单位kg/m³）满足连续统假设的物质每单位体积的质量。和比容相关联。 |
| Dimension line | 尺寸线 |
A line on an engineering drawing with a numeral above it that shows the length of a feature, usually in millimetres. 工程图上的一条线，上面有一个数字，表示特征的长度，通常以毫米为单位。 |
| Coefficient of restitution (e) | 回弹系数（e） |
The ratio of the relative velocity of two colliding bodies after collision to that before. In perfectly elastic collisions e = 1; when all the impact energy is dissipated, e = 0. 两个碰撞体在碰撞后与碰撞前的相对速度之比。在完全弹性碰撞中e=1；当所有的冲击能量都消散时，e=0。 |
| Circular pitch | 齿距 |
The distance from the center of one gear tooth to the center of the next gear tooth measured on the pitch line. 在节线上测量的从一个轮齿中心到下一个轮齿中心的距离。 |
| Austempered steels | 等温钢 |
Medium to high carbon steels with improved mechanical properties as a result of austempering. After heating to between 800° and 900°C to form the austenite phase, they are quenched to, and held at, just above the martensite transformation range (between 260° and 370°C) to form bainite, before cooling further. Austempering of ductile cast irons results in a microstructure of bainite and spheroidal graphite. Austempered ductile irons have excellent toughness and wear properties. 由于等温淬火，机械性能得到改善的中高碳钢。在加热到800°和900°C之间形成奥氏体相后，将它们淬火并保持在略高于马氏体转变范围（260°和370°C之间）以形成贝氏体，然后进一步冷却。球墨铸铁的等温淬火导致贝氏体和球状石墨的微观结构。等温淬火球墨铸铁具有优异的韧性和耐磨性。 |
| Stabilizing treatment | 稳定化处理 |
(1) Before finishing to final dimensions, repeatedly heating a ferrous or nonferrous part to or slightly above its normal operating temperature and then cooling to room temperature to ensure dimensional stability in service. (2) Transforming retained austenite in quenched hardenable steels, usually by cold treatment. (3) Heating a solution-treated stabilized grade of austenitic stainless steel to 870 to 900 °C (1600 to 1650 °F) to precipitate all carbon as TiC, NbC, or TaC so that sensitization is avoided on subsequent exposure to elevated temperature. （1）在精加工至最终尺寸之前，反复加热含铁或非铁零件至或略高于其正常工作温度，然后冷却至室温，以确保使用中的尺寸稳定性。（2）在淬火可淬硬钢中转变残余奥氏体，通常通过冷处理。（3）将固溶处理的稳定等级奥氏体不锈钢加热至870至900°C（1600至1650°F），使所有碳沉淀为TiC、NbC或TaC，从而避免在随后暴露于高温时敏化。 |
| 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。 |
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