| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| 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。 |
| Stroke | 一击 |
1. (stroke length) (Unit m) The linear distance between top dead centre and bottom dead centre of a piston in a reciprocating engine or mechanism. 2. The movement of a piston or plunger in a reciprocating machine to execute a particular function; for example, the exhaust stroke of an engine in which the exhaust gases are expelled from a cylinder. 1.（冲程长度）（单位：m）往复式发动机或机构中活塞上止点和下止点之间的线性距离。2.活塞或柱塞在往复式机器中执行特定功能的运动；例如发动机的排气冲程，其中排气从气缸中排出。 |
| Plug | 螺塞 |
1. An object, usually tapered, used to block a hole to prevent fluid from escaping or flowing. 2. The central moveable part of a valve. 3. In the flow of a yield-stress fluid through a pipe or duct, the central region is often assumed to take the form of a plug with uniform axial velocity. 4. In thermoforming, a shaping tool that forces a heated plastic sheet into a female mould. 1.一种物体，通常为锥形，用于堵塞孔以防止流体逸出或流动。2.阀门的中心可移动部分。3.在屈服应力流体通过管道或管道的流动中，中心区域通常假定为具有均匀轴向速度的塞子形式。4.在热成型技术中，一种成型工具，将加热的塑料板压入阴模中。 |
| Fatigue wear | 疲劳磨损 |
Wear of a solid surface caused by fracture arising from material fatigue. 由材料疲劳引起的断裂引起的固体表面磨损。 |
| Cap screw | 帽螺钉 |
A bolt where the thread runs right up to the head and engages in a threaded hole or captive nut in an adjoining member. A finished screw 5mm or larger, used for fastening two pieces together by passing the screw through a clearance hole in one part and screwing in into a tapped hole in the other. A finished screw, used for fastening two pieces together by passing the screw through a clearance hole in one part and screwing it into a tapped hole in the other. Heads may be hexagon, round, flat, fillister or socket type. 一个5毫米或更大的螺钉，其螺纹一直延伸到头部，并与相邻构件的螺纹孔或外加螺母啮合,用于将两个部件固定在一起，方法是将螺钉穿过一个部分的间隙孔，然后拧入另一个部分的螺纹孔。头部可以是六角形、圆形、扁平形、圆角形或套筒形。 |
| Torsional shaft vibration | 扭轴振动 |
The rapid back-and-forth angular twisting along a rotating unbalanced shaft which reaches maxima at critical rotation speeds. Shaft eccentricity, unbalanced mass distribution, oscillatory torque, misalignment, etc. all influence torsional vibration. 沿旋转不平衡轴的快速来回角扭转，在临界转速下达到最大值。轴偏心、质量分布不平衡、振荡扭矩、未对准等都会影响扭转振动。 |
| 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。 |
| Thermochemical treatment | 热化学处理 |
Heat treatment carried out in a medium suitably chosen to produce a change in the chemical composition of the object by exchange with the medium. 在适当选择的介质中进行热处理，以通过与介质交换产生物体化学成分的变化。 |
| Essential conditions | 必要条件 |
Each type of failure to which bolted joints are subject is set up by three or four conditions. The conditions vary, depending on the mode of failure, but never number more than four. Eliminating any one of the essential conditions for a particular type of failure can prevent that type of failure. 螺栓连接所遭受的每种类型的故障都由三个或四个条件确定。根据故障模式的不同，情况会有所不同，但数量不得超过四个。消除特定类型故障的任何一个基本条件都可以防止该类型故障。 |
| Slip band | 滑带 |
A group of parallel slip lines so closely spaced as to appear as a single line when observed under an optical microscope. 一组平行滑移线，间距如此之近，以至于在光学显微镜下观察时显示为一条直线。 |
| 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。 |
| Load | 负载 |
For testing machines, a force applied to a test piece that is measured in units such as pound-force, newton, or kilogram-force. 对于试验机，施加在试件上的力，以磅力、牛顿或千克力等单位测量。 |
| Slack quenching | 欠速淬火 |
The incomplete hardening of steel due to quenching from the austenitizing temperature at a rate slower than the critical cooling rate for the particular steel, resulting in the formation of one or more transformation products in addition to martensite. 由于从奥氏体化温度以低于特定钢临界冷却速度的速度淬火而导致钢的不完全硬化，导致除马氏体外还形成一种或多种相变产物。 |
| Pulley | 带轮 |
A free or driven wheel on a shaft with an appropriately shaped rim to carry a flat belt, vee belt, notched belt, rope, or chain. Used to transmit power or motion. 轴上的自由轮或从动轮，具有适当形状的轮缘，以承载平皮带、V形皮带、槽口皮带、绳索或链条。用于传递动力或运动。 |
| X-ray thickness gauge | X射线厚度计 |
A device comprising an X-ray source and a detector used to determine the thickness of material in sheet or plate form, including metals, paper, plastics, rubber, and ceramics. 一种由X射线源和探测器组成的装置，用于测定片状或平板状材料的厚度，包括金属、纸张、塑料、橡胶和陶瓷。 |
| High-tensile bolt | 高强度螺栓 |
(high-tension bolt) A bolt manufactured from an alloy steel that has a high tensile strength of about 1 GPa. （高压螺栓）由合金钢制成的螺栓，具有约1GPa的高抗拉强度。 |
| Air pump | 气泵 |
A machine for providing a flow of air or for increasing or decreasing the mass and pressure of air in a closed container. The term pump is more usual when the working fluid is a liquid, while compressor is more usual for gases. 一种用于提供空气流动或用于增加或减少密闭容器中空气质量和压力的机器。当工作流体是液体时，术语泵更常用，而气体更常用压缩机。 |
| Minimum material condition | 最小材料条件 |
(minimum metal condition) The situation where the volume of a manufactured component corresponds to the lower limit of all toleranced external dimensions and to the upper limit for all internal dimensions. （最小金属条件）制造部件的体积对应于所有公差外部尺寸的下限和所有内部尺寸的上限的情况。 |
| Torsional angle (ϕ) | 扭转角（ψ） |
(Unit ° or rad) The angular deflexion between two locations on a straight bar subjected to a torque. （单位为°或rad）受扭矩作用的直杆上两个位置之间的角偏转。 |
| 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。 |
| Thermal energy (heat energy) (Unit J) | 热能（单位：J） |
The sensible and latent forms of internal energy. 内能的感知和潜在形式。 |
| Bond strength (Unit Pa) | 结合强度（单位Pa） |
The tensile, compressive or shear stress at which joints fail, e.g. by fracture or excessive deformation. 接头失效的拉伸、压缩或剪切应力，例如断裂或过度变形。 |
| Water jacket | 水套 |
A casing, typically of sheet metal, surrounding a machine, such as an engine, that requires cooling. Water is circulated through the jacket and a heat exchanger where the heat is removed. 机壳一种机壳，通常由金属板制成，围绕着需要冷却的机器，如发动机。水通过夹套和热交换器循环，在热交换器中热量被去除。 |
| 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。 |
| Age hardening | 时效硬化 |
Raising the strength and hardness of an alloy by heating a supersaturated solid solution at a relatively low temperature to induce precipitation of a finely dispersed second phase. Also known as aging or precipitation hardening. Hardening by aging, usually after rapid cooling or cold working. 通过在相对较低的温度下加热过饱和固溶体以诱导细分散的第二相沉淀来提高合金的强度和硬度。也称为时效或沉淀硬化。通常在快速冷却或冷加工后。 |
| U-tube | U型管 |
A device consisting of two vertical tubes connected at either the top or bottom by a length of tubing such that a U-shape is formed. 由两个垂直管组成的装置，在顶部或底部通过一段管子连接，形成U形。 |
| Valve plug | 阀塞 |
A conical or cylindrical plug, in which there are transverse holes, in a valve, such as a plug valve. Flow through the holes occurs when the plug is rotated. 阀门中的圆锥形或圆柱形阀塞，其中有横向孔，如旋塞阀。旋转阀塞时，会发生通过孔的流动 |
| Positive-displacement compressor | 容积式压缩机 |
Any type of compressor, including piston and rotary-screw types, that delivers a fixed volume of gas at high pressure per unit time. A positive-displacement pump delivers a fixed volume of fluid, usually a liquid, per unit time. 任何类型的压缩机，包括活塞式和旋转螺杆式，在单位时间内以高压输送固定体积的气体。容积泵每单位时间输送固定体积的流体，通常为液体。 |
| Regenerative pump | 涡流泵 |
(regenerative turbine pump, peripheral pump) A pump with a double-sided impeller having a large number of radial blades. The pressure of the pumped liquid increases progressively over several revolutions of the impeller. It is particularly suited to producing large heads at small flow rates without cavitation. （再生涡轮泵，外围泵）具有具有大量径向叶片的双面叶轮的泵。泵送液体的压力在叶轮的几圈内逐渐增加。它特别适合于在小流速下产生大水头且不产生气穴。 |
| Range of stress (Sr) | 应力范围（Sr） |
The algebraic difference between the maximum and minimum stress in one cycle—that is, Sr = Smax – Smin 一个循环中最大和最小应力之间的代数差，即Sr=Smax–Smin |
| Brayton cycle | 布雷顿循环 |
(Joule cycle) An air standard cycle that is the ideal cycle for a gasturbine engine. As shown on the diagram of pressure (p) ʋs specific volume (ʋ), it consists of four internally reversible processes: isentropic compression in a compressor (1–2), isobaric heat addition in a combustor (2–3), isentropic expansion in a turbine (3–4) and isobaric heat rejection. The cycle can be extended to include regeneration, reheating, and intercooling. （焦耳循环）一种空气标准循环，是燃气轮机发动机的理想循环。循环可以扩展到包括再生、再热和中冷。 |
| Creep modulus (Unit Pa) | 蠕变模量（单位Pa） |
The ratio of stress/strain at a chosen strain level obtained from creep tests, often plotted against time to show changes in stiffness. 从蠕变测试中获得的选定应变水平下的应力/应变比，通常随时间绘制以显示刚度的变化。 |
| Dislocation density | 位错密度 |
The total length of dislocation lines per unit volume, or the number of dislocation lines that cut through a unit cross-sectional area. 每单位体积的位错线的总长度，或穿过单位横截面积的位错线的数量。 |
| 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）。 |
| Minimum load (Pmin) | 最小负载（Pmin） |
In fatigue, the least algebraic value of applied load in a cycle. 在疲劳中，循环中施加载荷的最小代数值。 |
| Scatter | 分散 |
Data points or calculations are said to be scattered when they are not all the same. A ‘‘lot of scatter in preload’’ means wide variation in the preloads found in individual bolts. 当数据点或计算不尽相同时，它们被称为分散的。“预载的大量分散”意味着单个螺栓中的预载差异很大。 |
| Shrink fit | 过盈配合 |
A tight interference fit between two components resulting from heating an outer part and/or cooling an inner part to allow easy assembly. The outer component contracts on cooling, while the inner part expands on warming to ambient temperature, thus gripping the two parts together. 由于加热外部部件和/或冷却内部部件而导致的两个部件之间的紧密过盈配合，以便于组装。外部部件在冷却时收缩，而内部部件在加热到环境温度时膨胀，从而将两个部件夹在一起。 |
| Modulus of resilience | 回弹系数 |
The amount of energy stored in a material when loaded to its elastic limit. It is determined by measuring the area under the stress-strain curve up to the elastic limit. 当加载到其弹性极限时，材料中储存的能量量。通过测量应力-应变曲线下直至弹性极限的面积来确定。 |
| Cleavage fracture | 解理断裂 |
A fracture, usually of a polycrystalline metal, in which most of the grains have failed by cleavage, resulting in bright reflecting facets. It is one type of crystalline fracture and is associated with low energy brittle fracture. Contrast with shear fracture. A fracture created by splitting (cleavage), as between layers in materials like slate or mica. In brittle metals, and brittle microconstituents in alloys, cleavage occurs along particular crystal planes. 一种通过分裂（劈裂）产生的裂缝断裂，通常是多晶金属的断裂，其中大部分晶粒因解理而失效，产生明亮的反射面。它是一种结晶性断裂，与低能脆性断裂有关。与剪切断裂相对。如板岩或云母等材料的层之间。在脆性金属和合金中的脆性微量成分中，沿特定晶面发生解理。 |
| Prying | 撬动 |
The magnification of an External load by a pseudolever action when that load is an Eccentric tensile load. 当外部荷载为偏心拉伸荷载时，通过伪杠杆作用放大外部荷载。 |
| Extra spring | 额外弹簧 |
A temper of nonferrous alloys and some ferrous alloys corresponding approximately to a coldworked state above full hard beyond which further cold work will not measurably increase the strength and hardness. 有色金属合金和一些铁合金的回火状态，大约对应于高于全硬的冷加工状态，超过该状态进一步冷加工将不会显着增加强度和硬度。 |
| Longitudinal direction | 纵向 |
The principal direction of flow in a worked metal. See also normal direction and transverse direction. 加工金属中的主要流动方向。另请参见法向和横向。 |
| Combustion chamber | 炉膛 |
1. In a piston engine, the volume between the head of an individual cylinder and the crown of the piston in which the fuel–air mixture burns during each power stroke of the engine. 2. (combustor) In a gas-turbine engine, a ramjet, an afterburner, or a rocket motor, the component, often cylindrical or annular in shape, in which the fuel–air mixture burns in a continuous-flow process. 1.在活塞式发动机中，在发动机的每个动力冲程中，燃料-空气混合物燃烧的单个气缸盖和活塞顶之间的体积。2.（燃烧室）在燃气涡轮发动机、冲压发动机、加力燃烧室或火箭发动机中，燃料-空气混合物在连续流动过程中燃烧的部件，通常为圆柱形或环形。 |
| Median fatigue strength at N cycles | N次循环的中位疲劳强度 |
An estimate of the stress level at which 50% of the population would survive N cycles. The estimate is derived from a particular point of the fatigue life distribution, because there is no test procedure by which a frequency distribution of fatigue strengths at Ncycles can be directly observed. 估计50%的量在N个周期内生存的压力水平。该估计值来自疲劳寿命分布的一个特定点，因为没有试验程序可以直接观察N次循环疲劳强度的频率分布。 |
| Retaining clip | 固定夹 |
(R-clip, hair cotter pin) A wire clip roughly with the shape of the letter R. The straight part of the clip passes through a hole drilled into a shaft or rod such that a wheel is held in position on the shaft, or the shaft is prevented from moving axially. （R形夹，开口销）大致与字母R形状相同的线夹。线夹的直线部分穿过钻在轴或杆上的孔，从而将车轮固定在轴上，或防止轴轴向移动。 |
| Forced-air quench | 强制空气淬火 |
A quench utilizing blasts of compressed air against relatively small parts such as a gear. 利用压缩空气冲击相对较小的零件（例如齿轮）进行的淬火。 |
| Valve | 阀门 |
Any of various manual or automatic devices that are able to initiate, regulate, or stop the flow of a fluid through a conduit or from a closed container. 任何一种手动或自动装置，能够启动、调节或停止通过导管或封闭容器的流体流动。 |
| 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。 |
| Constant life diagram | 恒定寿命图 |
A plot of experimentally derived fatigue-life data; perhaps the most complex and complete of the popular charts used to represent such data. 实验得出的疲劳寿命数据图；可能是用于表示此类数据的最复杂和最完整的流行图表。 |
| Submerged-electrode furnace | 浸入式电极炉 |
A furnace used for liquid carburizing of parts by heating molten salt baths with the use of electrodes submerged in the ceramic lining. 一种通过使用浸入陶瓷衬里中的电极加热熔融盐浴对零件进行液体渗碳的炉。 |
| Milling | 铣削 |
A machining process, typically for metals and plastics, in which a multi-tooth rotary cutter removes material to produce flat or profiled surfaces, slots, grooves, etc. Milling is a machining process in which metal is removed by a rotating multiple-tooth cutter; each tooth removes a small amount of metal with each revolution of the spindle. Because both workpiece and cutter can be moved in more than one direction at the same time, surfaces having almost any orientation can be machined. 一种加工工艺，通常用于金属和塑料，其中多齿旋转刀具去除材料以产生平坦或异形表面、槽、槽等。金属由旋转多齿刀具去除；主轴每转一圈，每个齿都会去除少量金属。因为工件和刀具可以同时在多个方向上移动，所以几乎可以加工任何方向的表面。 |
| 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。 |
| Accelerated testing | 加速测试 |
A type of testing, for rates of wear, fatigue, corrosion etc., in which failure times are reduced by employing greater loads, more frequent power cycling, higher vibration levels, higher humidity, higher temperatures, greater potential differences etc. than would be encountered in normal operation. 一种测试类型，用于测试磨损率、疲劳率、腐蚀率等，通过采用比正常运行中更大的负载、更频繁的功率循环、更高的振动水平、更高湿度、更高温度、更大的电位差等，减少故障时间。 |
| Shear joint | 剪切接头 |
A joint which is subjected primarily to loads acting more or less perpendicular to the axes of the bolts. 主要承受或多或少垂直于螺栓轴线的载荷的接头。 |
| Beta annealing | β退火 |
Producing a beta phase by heating certain titanium alloys in the temperature range of which this phase forms followed by cooling at an appropriate rate to prevent its decomposition. 通过在形成β相的温度范围内加热某些钛合金，然后以适当的速率冷却以防止其分解，从而产生β相。 |
| Pressure snubber | 压力缓冲器 |
(pressure-pulse snubber) A device used for filtering, dampening, and the protection of transducers, pressure gauges, and switches, from pressure surges, pressure spikes, and water hammer. A typical design uses a fixed mesh or porous metal disc installed in an inline body. In a piston-type pressure-gauge snubber, a piston is forced against an orifice leading to the gauge. （压力脉冲缓冲器）一种用于过滤、阻尼和保护传感器、压力表和开关免受压力浪涌、压力尖峰和水锤影响的装置。典型的设计使用安装在内联阀体中的固定网格或多孔金属盘。在活塞式压力表缓冲器中，活塞被压靠在通向压力表的孔口上。 |
| Belt drive | 带传动 |
Transmission of motion from one shaft to another by means of a continuous plain, or toothed, flexible band (belt) passing over pulleys. In contrast to chain drives, belt drives tend to be employed in low-torque applications. Reduction in transmissible power may occur due to stretch of a plain transmission belt which results in slack in the drive (belt creep) or slip of a belt on a driving or driven pulley (belt slip). 通过穿过滑轮的连续平带或带齿柔性带（带）将运动从一根轴传递到另一根轴。与链条传动相比，皮带传动往往用于低扭矩应用。由于普通传动带的拉伸可能会导致传动松弛（皮带蠕变）或主动或从动皮带轮上的皮带打滑（皮带打滑），从而导致传动功率降低。 |
| Archimedes Wave Swing | 阿基米德波摆动 |
A machine for tidal-power energy generation consisting of two concentric, air-filled submerged cylinders. The inner lower cylinder is tethered to the ocean floor while the upper floater unit, which is closed at the top, moves up and down due to the variations in hydrostatic pressure caused by the wave motion. The relative movement of the two cylinders is used to generate electricity in which linear motion replaces the more common rotary motion of an electromagnetic generator. 一种用于潮汐能发电的机器，由两个同心的充气水下气缸组成。内部下部圆柱体系在海底，而顶部封闭的上部浮子单元由于波浪运动引起的静水压力变化而上下移动。两个气缸的相对运动用于发电，其中直线运动取代了电磁发电机更常见的旋转运动。 |
| Transgranular fracture | 穿晶断裂 |
Fracture in crystalline materials where the path of cracking is predominantly across grains. 晶体材料中的断裂，其中裂纹路径主要跨越晶粒。 |
| Martempering | 淬火 |
(1) A hardening procedure in which an austenitized ferrous workpiece is quenched into an appropriate medium whose temperature is maintained substantially at the Ms of the workpiece, held in the medium until its temperature is uniform throughout–but not long enough to permit bainite to form–and then cooled in air. The treatment is frequently followed by tempering. (2) When the process is applied to carburized material, the controlling Ms temperature is that of the case. This variation of the process is frequently called marquenching. （1）一种淬火工艺，将奥氏体化铁质工件淬火到适当的介质中，该介质的温度基本保持在工件的Ms，保持在该介质中直到其温度在整个过程中均匀，但不足以形成贝氏体，然后在空气中冷却。处理后经常进行回火。（2） 当该工艺应用于渗碳材料时，控制Ms温度与实际情况相同。这个过程的变化经常被称为淬火。 |
| Isothermal annealing | 等温退火 |
Austenitizing a ferrous alloy and then cooling to and holding at a temperature at which austenite transforms to a relatively soft ferrite carbide aggregate. 将铁合金奥氏体化，然后冷却至奥氏体转变为相对软的铁素体碳化物集合体的温度并保持该温度。 |
| Dynamic coupling | 动态耦合 |
In vibrations, the existence of inertial terms depending on mass in the governing equations, so that there is only a force if there is a corresponding acceleration. 在振动中，惯性项的存在取决于控制方程中的质量，因此只有当有相应的加速度时才有力。 |
| 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。 |
| Lockbolt | 锁紧螺栓 |
A fastener which bears a superficial resemblance to a bolt, but which engages a collar (instead of a nut) with annular grooves (instead of threads). The collar is swaged over the grooves on the male fastener to develop preload. 表面上类似于螺栓的紧固件，但与环槽（而不是螺纹）接合的轴环（而不是螺母）。套环在阳紧固件上的凹槽上锻造，以产生预紧力。 |
| Crack size (a) | 裂纹尺寸（a） |
A lineal measure of a principal planar dimension of a crack. This measure is commonly used in the calculation of quantities descriptive of the stress and displacement fields. In practice, the value of crack size is obtained from procedures for measurement of physical crack size, original crack size, or effective crack size, as appropriate to the situation under consideration. 裂纹主平面尺寸的线性度量。这种测量通常用于计算描述应力场和位移场的量。在实践中，裂纹尺寸的值是通过测量物理裂纹尺寸、原始裂纹尺寸或有效裂纹尺寸的程序获得的，视情况而定。 |
| Actual value | 实际价值 |
The output of a plant that is being controlled, i.e. the controlled variable. Not directly accessible by the control system, as it can only be measured by a sensor which may distort the measurement. 受控设备的输出，即受控变量。控制系统不能直接访问，因为它只能由可能会扭曲测量结果的传感器测量。 |
| Austenitic grain size | 奥氏体晶粒尺寸 |
The size attained by the grains of steel when heated to the austenitic region; may be revealed by appropriate etching of cross sections after cooling to room temperature. 当加热到奥氏体区域时钢晶粒达到的尺寸；冷却至室温后，可通过适当蚀刻横截面来显示。 |
| 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。 |
| Thermomechanical working | 热机械加工 |
A general term covering a variety of processes combining controlled thermal and deformation treatments to obtain specific properties. Same as thermal-mechanical treatment. 一个通用术语，涵盖结合受控热处理和变形处理以获得特定性能的各种工艺。与热机械处理相同。 |
| Vacuum servo | 真空服务器 |
A vacuum-operated servomotor which is used in a motor vehicle to provide a brake effort greater than the capability of the driver. 一种真空操作的伺服电机，用于机动车中，以提供大于驾驶员能力的制动力。 |
| Athermal transformation | 非热变化 |
A reaction that proceeds without benefit of thermal fluctuations; that is, thermal activation is not required. In contrast, a reaction that occurs at constant temperature is an isothermal transformation; thermal activation is necessary in this case and the reaction proceeds as a function of time. 在没有热波动的情况下进行的反应；也就是说，不需要热激活。相反，在恒温下发生的反应是等温转变。在这种情况下，热活化是必要的，并且反应作为时间的函数进行。 |
| Velocity ratio | 速度比 |
1. The ratio between the input velocity to a machine, train of gears, etc. and the output velocity. 2. The ratio between the displacement of an applied force at one part of a mechanism and the movement of the load at a different part. 1.机器、齿轮系等的输入速度与输出速度之间的比率。2.在机构的一个部分处施加的力的位移与在不同部分处的载荷的移动之间的比率。 |
| Wear | 磨损 |
Damage to a solid surface, generally involving progressive loss of material, due to relative motion between that surface and a contacting surface or substance. The deterioration of a component or structure with time and usage, often impairing the function for which it was designed, owing to abrasion, corrosion, fatigue, friction, etc. during relative motion of parts. The wear factor (K), with unit mm³/N.m, is an empirical dimensional factor that quantifies surface wear due to mechanical frictional contact, and defined by K = /Fs where is the worn volume (in mm³), F is the contact load (in N), and s is the sliding distance (in m). 由于固体表面与接触表面或物质之间的相对运动，对固体表面的损坏，通常涉及材料的渐进损失。部件或结构随时间和使用而劣化，通常由于部件相对运动过程中的磨损、腐蚀、疲劳、摩擦等而损害其设计功能。磨损系数（K），单位为mm³/N.m、 是量化机械摩擦接触导致的表面磨损的经验尺寸因子，由K=/Fs定义，其中是磨损体积（单位：mm³），F是接触载荷（单位：N），s是滑动距离（单位：m）。 |
| Millimetre of water | 毫米水柱 |
A non-SI unit of pressure equal to the pressure exerted by a vertical column of water 1 mm high. Approximately equal to 9.81 Pa. 一种非SI压力单位，等于1毫米高的垂直水柱施加的压力。大约等于9.81Pa。 |
| Acoustic droplet ejection | 声液滴喷射 |
The ejection of small droplets from the surface of a liquid that results from focusing high-intensity ultrasound near the surface. 由于在表面附近聚焦高强度超声波而从液体表面喷射出小液滴。 |
| Dead centre | 止点 |
The point at which, in a crank mechanism, the piston connecting rod and crank are all in line so that there can be no driving moment. 在曲柄机构中，活塞连杆和曲柄都在一条线上，因此不会有驱动力矩。 |
| 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。 |
| Verified loading range | 验证加载范围 |
For testing machines, the range of indicated loads for which the testing machine gives results within the permissible variation specified. 对于试验机，试验机在规定允许偏差范围内给出结果的指示载荷范围。 |
| 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。 |
| Joint diagrams | 接合处关系图 |
Mathematical diagrams which illustrate the forces on and deflections of fasteners and joint members. 说明紧固件和连接件上的力和变形的数学图。 |
| Toggle (toggle clamp) | 拨动（拨动夹） |
A device consisting of two pinned levers that are almost in line between two end points in the same plane. Bringing the levers into line generates large forces between the ends. Used to obtain a large mechanical advantage or as a locking mechanism. 由两个销杆组成的装置，在同一平面的两个端点之间几乎成一条直线。将杠杆对齐会在端部之间产生较大的力。用于获得较大的机械优势或用作锁定机构。 |
| Single thread | 单头螺纹 |
A screw thread cut around a cylinder having a single start in which the lead is equal to the pitch. 一种螺纹，在一个圆柱体上切割而成，具有一个单一的起点，在这个起点上，导程等于螺距。 |
| 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。 |
| Scleroscope hardness number (HSc or HSd) | 硬化镜硬度值（HSc或HSd） |
A number related to the height of rebound of a diamond-tipped hammer dropped on the material being tested. It is measured on a scale determined by dividing into 100 units the average rebound of the hammer from a quenched(to maximum hardness) and untempered AISI W5 tool steel test block. 与落在被测材料上的菱形锤的回弹高度相关的数字。通过将锤子从淬火（达到最大硬度）和未淬火的AISI W5工具钢试块上的平均回弹分为100个单位来测量。 |
| 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。 |
| V-block | V型块 |
A block having a 90° V-shaped recess; used in a workshop to hold round workpieces. 具有90°V形凹槽的块体；在车间里用来装圆形工件。 |
| Lead of thread | 螺纹导程 |
On a single threaded screw, the distance the screw or nut advances in one complete revolution. 在单螺纹螺钉上，螺钉或螺母在一整圈中前进的距离。 |
| 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。 |
| Residual preload | 残余预载荷 |
The tension which remains in an unloaded bolted joint after Relaxation. 松弛后未加载螺栓连接中保持的张力。 |
| Radial wave equation | 径向波动方程 |
A differential equation describing the transmission of a wave in a system with radial symmetry. 描述波在径向对称系统中传输的微分方程。 |
| Strain-hardening exponent (n value) | 应变硬化指数（n值） |
The value n in the relationship σ = Kεn, where σ is the true stress, ε is the true strain, and K, the strength coefficient, is equal to the true stress at a true strain of 1.0. The strain hardening exponent is equal to the slope of the true stress/true strain curve up to maximum load, when plotted on log-log coordinates. The n-value relates to the ability of a sheet of material to be stretched in metalworking operations. The higher the n-value, the better the formability(stretchability). Also known as the strain-hardening coefficient. 关系式σ=Kεn中的值n，其中σ是真应力，ε是真应变，K是强度系数，等于真应变为1.0时的真应力。在对数坐标上绘制时，应变硬化指数等于真应力/真应变曲线的斜率，直到最大载荷。n值与一片材料在金属加工操作中拉伸的能力有关。n值越高，成形性（拉伸性）越好。也称为应变硬化系数。 |
| Plane stress | 平面应力 |
The stress condition in linear-elastic fracture mechanics in which the stress in the thickness direction is zero; most nearly achieved in loading very thin sheet along a direction parallel to the surface of the sheet. Under plane-stress conditions, the plane of fracture instability is inclined 45° to the axis of the principal tensile stress. 线弹性断裂力学中厚度方向上的应力为零的应力条件；在沿着平行于薄片表面的方向加载非常薄的薄片时最接近。在平面应力条件下，断裂失稳平面与主拉应力轴倾斜45°。 |
| Auxiliary power unit (APU) | 辅助动力装置（APU） |
In aircraft–gas–turbine applications, a small gas turbine used to provide start-up power, electrical and hydraulic power, and compressed air for cabin ventilation. In other applications, an APU may be a gas turbine or internal-combustion engine used to provide emergency power. 在飞机-燃气轮机应用中，小型燃气轮机用于提供启动动力、电力和液压动力以及用于机舱通风的压缩空气。在其他应用中，APU可以是用于提供应急动力的燃气轮机或内燃机。 |
| Twist drill | 麻花钻 |
A hardened-steel drill bit having one or more helical flutes running from a conical tip to the smooth part of the shank. 一种淬火钢钻头，具有一个或多个螺旋槽，从锥形尖端延伸到柄部的光滑部分。 |
| 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。 |
| Time quenching | 时间淬火 |
A term used to describe a quench in which the cooling rate of the part being quenched must be changed abruptly at some time during the cooling cycle. 用于描述淬火的术语，其中被淬火零件的冷却速率必须在冷却循环的某个时间突然改变。 |
| Intergranular fracture | 沿晶破裂 |
Brittle fracture of a metal in which the fracture is between the grains, or crystals, that form the metal. Also called intercrystalline fracture. 金属的脆性断裂，断裂位于形成金属的晶粒或晶体之间。又称晶间破裂。 |
| Full-size fastener | 全尺寸紧固件 |
Finished fastener with a shank diameter of ds ≈ d or ds > d, or screw threaded to the head, or fully threaded stud. 柄径为ds≈d或ds>d的紧固件，或螺纹连接到头部，或全螺纹螺柱。 |
| 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。 |
| Vacuum relief valve | 真空安全阀 |
A valve that admits gas to a system under vacuum, should the degree of vacuum become excessive. 如果真空度过高，允许气体在真空下进入系统的阀门。 |
| Tolerances | 公差 |
A fractional allowance for variation from the specifications. In mass production, using automatic machines, parts are intended to be completely or partially interchangeable, and in batch production parts should ideally fit without the need for selection. In practice it is impossible for mass-produced parts to have exactly the same size, owing to tool wear, variations in raw materials, thermal effects, etc. In consequence, variations from exactness, termed tolerances, are assigned to what is permissible on the basic size. 与规范不同的部分公差。在大规模生产中，使用自动机器时，零件应完全或部分可互换，在批量生产中，零件应理想匹配，无需选择。在实践中，由于刀具磨损、原材料变化、热效应等原因，批量生产的零件不可能具有完全相同的尺寸。因此，将精度偏差（称为公差）指定给基本尺寸上允许的尺寸。 |
| Computer control | 电脑控制 |
The control of an engineering device or system by pre-programmed computer or by feedback control. 通过预编程计算机或反馈控制对工程设备或系统进行控制。 |
| Absolute expansion | 绝对扩张 |
The true volumetric expansion of a liquid with temperature, after account is taken of any expansion of the container in which it is held. 考虑到容纳液体的容器的任何膨胀后，液体随温度的真实体积膨胀。 |
| 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。 |
| Manometer | 压力计 |
An instrument used in the measurement of a pressure difference in a fluid (manometry). 用于测量流体压力差（测压）的仪器。 |
| Fatigue striations | 疲劳条纹 |
Parallel lines frequently observed in electron microscope fractographs or fatigue-fracture surfaces. The lines are transverse to the direction of local crack propagation; the distance between successive lines represents the advance of the crack front during the one cycle of stress variation. 在电子显微镜断口图或疲劳断口表面中经常观察到平行线。这些线横向于局部裂纹扩展方向；连续线之间的距离表示在一个应力变化周期内裂纹前沿的前进。 |
| 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。 |
| Residual strength (Unit N) | 剩余强度（单位：N） |
The strength of a damaged body containing defects induced by microcracking, thermal shock, etc. 包含由微裂纹、热冲击等引起的缺陷的受损体的强度。 |
| Millimetre of mercury | 毫米汞柱 |
A non-SI unit of pressure equal to the pressure exerted by a vertical column of mercury 1 mm high. Approximately equal to 133.3 Pa or 1 torr. 一种非SI压力单位，等于1毫米高的垂直水银柱施加的压力。大约等于133.3Pa或1托。 |
| Bypass ratio | 旁路比 |
In a turbofan engine, the ratio of the mass flow rate of the bypass stream to the mass flow rate through the core of the engine. 在涡扇发动机中，旁通流的质量流量与通过发动机核心的质量流量之比。 |
| Newton’s law of viscosity | 牛顿内摩擦定律 |
The shear stress between two parallel layers of fluid is proportional to the velocity of one relative to that of the other, and inversely proportional to the distance between them. The constant of proportionality is the dynamic viscosity μ. For a Newtonian fluid μ is independent of pressure gradient, shear stress, and strain, but may change with temperature and pressure. 两个平行流体层之间的剪切应力与其中一层相对于另一层的速度成正比，与它们之间的距离成反比。比例常数是动态粘度μ。对于牛顿流体，μ与压力梯度、剪切应力和应变无关，但可能随温度和压力而变化。 |
| Vapour-pressure thermometer | 蒸汽压力温度计 |
(vapour-filled thermometer) A type of fluidexpansion thermometer in which the working fluid is a volatile liquid. （蒸汽填充温度计）一种流体膨胀温度计，其中工作流体为挥发性液体。 |
| Air-hardening steel | 空气硬化钢 |
A steel containing sufficient carbon and other alloying elements to harden fully during cooling in air or other gaseous mediums from a temperature above its transformation range. The terms should be restricted to steels that are capable of being hardened by cooling in air in fairly large sections, about 2 in. (50 mm) or more in diameter. Same as self-hardening steel. 一种钢，含有足够的碳和其他合金元素，可以在空气或其他气体介质中从高于其转变范围的温度冷却过程中完全硬化。这些术语应仅限于能够通过在相当大的截面（直径约2英寸（50毫米）或更大）中通过空气冷却而硬化的钢。与自硬钢相同。 |
| 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。 |
| Volume (Unit m³) | 体积（单位m³） |
The amount of space occupied by a specified mass of substance or by an object. 一定质量的物质或物体占据的空间量。 |
| Mean stress (Unit Pa) | 平均应力（单位 Pa） |
The average of the maximum and minimum stresses for a material subjected to a stress cycle, as in a fatigue test. 承受应力循环的材料的最大和最小应力的平均值，如在疲劳试验中。 |
| Hardness | 硬度 |
A measure of the resistance of a material to surface indentation or abrasion; may be thought of as a function of the stress required to produce some specified type of surface deformation. There is no absolute scale for hardness; therefore, to express hardness quantitatively, each type of test has its own scale of arbitrarily defined hardness. Indentation hardness can be measured by Brinell hardness test, Rockwell hardness test, Vickers hardness test, Knoop hardness test, and the Scleroscope hardness test. The ability of a ductile material to resist permanent deformation. It is a measure of plastic flow properties determined principally by indentation testing, but scratch hardness and rebound hardness are also employed. hardness scales The different measures of hardness given by different tests, such as indentation pressure in the Brinell and in the Vickers hardness tests, and the different Rockwell hardness numbers. 测量材料对表面压痕或磨损的阻力；可以认为是产生某些特定类型的表面变形所需的应力的函数。硬度没有绝对刻度，因此为了定量表示硬度，每种类型的试验都有自己的任意定义硬度等级。压痕硬度可通过布氏硬度试验、洛氏硬度试验，维氏硬度试验和努氏硬度试验以及硬化镜硬度试验进行测量。延展性材料具有抵抗永久变形的能力，它是主要通过压痕测试确定的塑性流动性能的量度，也使用划痕硬度和回弹硬度。硬度标度不同试验给出的不同硬度测量值，如布氏硬度试验和维氏硬度试验中的压痕压力，以及不同的洛氏硬度值。 |
| Flame hardening | 火焰硬化 |
A process for hardening the surfaces of hardenable ferrous alloys in which an intense flame is used to heat the surface layers above the upper transformation temperature, whereupon the workpiece is immediately quenched. 一种用于硬化可硬化铁合金表面的工艺，其中使用强烈的火焰将表面层加热到转变温度上限以上，然后立即对工件进行淬火。 |
| Die | 模具 |
1. A tool having an appropriately-shaped hole through which material may be extruded or drawn. 2. A tool employed in forging. 3. A block having the male or female shape employed in stamping operations. 4. A thick circular disc, driven by a die wrench, with internally-threaded cutting edges for producing a screw thread. A die wrench (die stock) holds a screw-cutting die and has two projecting arms for applying the torque necessary to cut the thread. A die having a hexagonal or square shape (die nut), driven by a spanner, is used in confined spaces where a die wrench cannot be rotated through a full circle. 1.一种具有适当形状的孔的工具，通过该孔可以挤压或拉伸材料。2.一种用于锻造的工具。3.一种用于冲压操作的具有阳或阴形状的块体。4.一种由模具扳手驱动的厚圆盘，具有用于产生螺纹的内螺纹切削刃。冲模扳手（冲模）装有一个螺旋切割模，并有两个突出臂，用于施加切割螺纹所需的扭矩。由扳手驱动的六边形或方形模具（模具螺母）用于模具扳手无法旋转一整圈的受限空间。 |
| Hypoeutectic alloy | 亚共晶合金 |
In an alloy system exhibiting a eutectic, any alloy whose composition has an excess of base metal compared with the eutectic composition, and whose equilibrium microstructure contains some eutectic structure. 在呈现共晶的合金系统中，其成分比共晶成分多的任何合金，其平衡微观结构包含一些共晶结构。 |
| 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。 |
| 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。 |
| Fastener specification | 紧固件规格 |
A precise statement of set requirements to be satisfied by a fastener, its material, or its processing. It also indicates the procedure used to determine whether the requirements given are satisfied. 对紧固件、其材料或加工过程要满足的设定要求的精确陈述。它还指出了用于确定是否满足给定要求的程序。 |
| Fretting fatigue | 微动疲劳 |
Fatigue fracture that initiate at a surface area where fretting has occurred. The progressive damage to a solid surface that arises from fretting. 在发生微动的表面区域开始的疲劳断裂。由微动引起的对固体表面的渐进性损坏。 |
| Sharp-notch strength | 锐缺口强度 |
The notch tensile strength measured using specimens with very small notch root radii (approaching the limit for machining capability); values of sharp-notch strength usually depend on notch root radius. 使用缺口根部半径非常小（接近加工能力极限）的试样测量的缺口抗拉强度；锐缺口强度值通常取决于缺口根部半径。 |
| Maximum allowable operating pressure (Unit Pa) | 最大允许使用压力（单位Pa） |
The highest pressure at which any pressure system may be operated, usually 10 to 20% below the maximum allowable working pressure. 任何压力系统可运行的最高压力，通常比最大允许工作压力低10%至20%。 |
| Taper pins | 圆锥销 |
A pin or peg of circular cross section that tapers along its length. Steel pins used for locating and holding the machine parts in position on a shaft. 沿其长度逐渐变细的圆形横截面的销钉或销钉。用于在轴上定位和固定机器零件的钢销。 |
| Modulus of elasticity (E) | 弹性模量（E） |
The measure of rigidity or stiffness of a metal; the ratio of stress, below the proportional limit, to the corresponding strain. In terms of the stress-strain diagram, the modulus of elasticity is the slope of the stress-strain curve in the range of linear proportionality of stress to strain. 金属的刚度或刚度的量度；低于比例极限的应力与相应应变之比。根据应力应变图，弹性模量是应力应变曲线在应力应变线性比例范围内的斜率。 |
| Strain gage | 应变计 |
A device for measuring small amounts of strain produced during tensile and similar tests on metal. A coil of fine wire is mounted on a piece of paper, plastic, or similar carrier matrix (backing material), which is rectangular in shape and usually about 25 mm (1.0 in.) long. This is glued to a portion of metal under test. As the coil extends with the specimen, its electrical resistance increases in direct proportion. This is known as bonded resistance-strain gage. Other types of gages measure the actual deformation. Mechanical, optical, or electronic devices are sometimes used to magnify the strain for easier reading. 一种测量金属拉伸和类似试验中产生的少量应变的装置。将一卷细线安装在一张纸、塑料或类似载体基质（背衬材料）上，该载体基质呈矩形，通常约25mm（1.0in.）长，这是粘在测试金属的一部分。随着线圈随试样延伸，其电阻成正比增加，这被称为粘结电阻应变计。其他类型的量规测量实际变形。机械、光学或电子设备有时用于放大应变以便于读取。 |
| 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。 |
| Serrations | 锯齿 |
A row of notches or tooth-like projections on an edge or surface. On an engineering drawing, serrations on the surface of a circular component are shown over about 60° of arc. 边缘或表面上的一排凹口或齿状突起。在工程图纸上，圆形部件表面的锯齿超过约60°的圆弧。 |
| Cooling stresses | 冷却应力 |
Residual stresses resulting from nonuniform distribution of temperature during cooling. 冷却过程中温度分布不均匀导致的残余应力。 |
| Acicular ferrite | 针状铁素体 |
A highly substructured non-equiaxed ferrite that forms upon continuous cooling by a mixed diffusion and shear mode of transformation that begins at a temperature slightly higher than the temperature transformation range for upper bainite. It is distinguished from bainite in that it has a limited amount of carbon available; thus, there is only a small amount of carbide present. Ferrite crystallite growing, apparently, as in the course of bainitic transformation. It has a lath-like shape and an increased dislocation 一种高度亚结构的非等轴铁素体，在连续冷却时通过混合扩散和剪切相变模式形成，其开始温度略高于上贝氏体的温度转变范围。它与贝氏体的区别在于它的碳含量有限。因此，仅存在少量碳化物。显然，铁素体微晶在贝氏体转变过程中生长。它具有板条状的形状和增加的位错。 |
| Lobe | 凸轮 |
The projecting part such as rotor lobe or the cam lobe. 转子凸角或凸轮凸角等突出部分。 |
| 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。 |
| Tare weight (Unit N) | 皮重（单位N） |
The weight of an empty container. 空容器的重量。 |
| Bearing strength | 承载强度 |
The maximum bearing stress that a material is capable of sustaining. 材料能够承受的最大承载应力。 |
| 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。 |
| Congruent melting point (Unit K) | 全等熔点（单位K） |
congruent melting point (Unit K) The temperature at which a solid substance at a specified pressure changes phase to a liquid of identical composition. 一致的熔点（单位K）固体物质在特定压力下相变为具有相同成分的液体时的温度。 |
| Case | 包盖 |
That portion of a ferrous alloy, extending inward from the surface, whose composition has been altered so that it can be case hardened. Typically considered to be the portion of the alloy (a) whose composition has been measurably altered from the original composition, (b) that appears dark on an etched cross section, or (c) that has a hardness, after hardening, equal to or greater than a specified value. Contrast with core. 铁合金的一部分，从表面向内延伸，其成分已经改变，可以进行表面硬化。通常被认为是合金的一部分，（a）其成分与原始成分发生了可测量的变化，（b）在蚀刻横截面上呈黑色，或（c）硬化后硬度等于或大于规定值。与核心形成对比。 |
| Free joint | 万向节 |
The joint on a robot arm and wrist that causes the greatest end-effector movement when a specified force is applied to the end effector, i.e. that has the lowest stiffness with regard to the force. 机器人手臂和手腕上的关节，当指定的力施加到末端执行器时，会导致末端执行器的最大运动，即相对于力具有最低刚度。 |
| 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。 |
| Typical basis | 典型基础 |
The typical property value is an average value. No statistical assurance is associated with this basis. 典型的属性值是平均值。没有与此基础相关的统计保证。 |
| Acoustic separation | 声学分离 |
(Unit m) The separation of particles in a fluid using standing acoustic waves, typically ultrasound, to drive them to nodal points (acoustic particle concentration). （单位m）使用驻声波（通常是超声波）将流体中的粒子分离，以将它们驱动到节点（声学粒子浓度）。 |
| Active accommodation | 主动适应能力 |
The use of information from sensors, for example, in a vision system, that allows a robot to show accommodation to the environment. 使用来自传感器的信息，例如在视觉系统中，允许机器人显示对环境的适应。 |
| 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。 |
| Condensation shock | 冷凝冲击 |
For supersonic flow of a moist gas through a divergent nozzle, condensation occurs in the form of spontaneous nucleation at some point downstream of that at which the temperature falls to the saturation temperature. The condensation process proceeds rapidly, and results in a fairly thick discontinuity termed a condensation shock. 对于通过发散喷嘴的湿气体超音速流动，在温度降至饱和温度的点下游的某个点处，冷凝以自发成核的形式发生。凝结过程进行得很快，导致相当厚的不连续性，称为凝结激波。 |
| Principal stress (normal) | 主应力（正常） |
The maximum or minimum value of the normal stressat a point in a plane considered with respect to all possible orientations of the considered plane. On such principal planes the shear stress is zero. There are three principal stresses on three mutually perpendicular planes. The state of stress at a point may be: (1) uniaxial, a state of stress in which two of the three principal stresses are zero; (2) biaxial, a state of stress in which only one of the three principal stresses is zero; or (3) triaxial, a state of stress in which none of the principal stresses is zero. Multiaxial stress refers to either biaxial or triaxial stress. 相对于所考虑平面的所有可能方向，所考虑平面中某点处的法向应力的最大值或最小值。在这样的主平面上，剪切应力为零。在三个相互垂直的平面上有三个主应力。一点的应力状态可以是：（1）单轴，三个主应力中的两个为零的应力；（2）双轴，三个主应力中只有一个为零的应力状态；或（3）三轴，即主应力均不为零的应力状态。多轴应力是指双轴或三轴应力。 |
| 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。 |
| Surface tension (σ, γ) (Unit N/m) | 表面张力（σ，γ）（单位：N/m） |
At the interface between a liquid and a gas or two immiscible liquids, unbalanced cohesive forces acting on the liquid molecules at the interface lead to the property surface tension which causes tensile forces to develop as if it were a skin or membrane. 液体和气体或两种不混溶液体之间的界面处，作用在界面处的液体分子上的不平衡内聚力导致表面张力的性质，从而导致张力的发展，就像皮肤或薄膜一样。 |
| Flat head | 平头 |
Flat top surface and a conical bearing surface. 平顶表面和锥形轴承表面。 |
| Pitch (Unit m) | 间距（单位：m） |
1. In a cascade of identical turbine or compressor blades, the distance between successive blades measured parallel to the leading edges. 2. For a screw thread, the distance between adjacent thread forms measured parallel to the thread axis. 3. For an aircraft, the vertical relationship between the nose and the horizon. The pitch axis is an axis in the plane of the wings of an aircraft, perpendicular to the centreline, about which the aircraft rotates. Pitch motion is the corresponding up or down movement of the aircraft nose. Pitch attitude is the angle between the centreline of an aircraft and the horizontal. The angle is positive when the nose is above its position when the centreline is horizontal. 1.在相同涡轮或压缩机叶片的叶栅中，平行于前缘测量的连续叶片之间的距离。2.对于螺纹，平行于螺纹轴线测量的相邻螺纹形状之间的距离。3.对于飞机，机头和水平线之间的垂直关系。俯仰轴是飞机机翼平面内垂直于中心线的轴，飞机绕中心线旋转。俯仰运动是飞机机头的相应向上或向下运动。俯仰姿态是飞机中心线与水平线之间的角度。当中心线水平时，当机头高于其位置时，角度为正。 |
| Compression ratio | 压缩率 |
The volume of a combustion chamber with the piston at the top of its stroke as a proportion of the total volume of the cylinder with the piston at the bottom of its stroke. For a piston engine, if the swept volume is SW and the clearance volume is CL, the compression ratio is given by ( SW + CL)/CL, i.e. it is a volume ratio rather than a pressure ratio. 活塞位于其冲程顶部的燃烧室的容积与活塞位于其冲程底部的气缸总体积的比例。对于活塞发动机，如果扫气量为SW，间隙容积为CL，则压缩比由(SW+CL)/CL给出，即它是体积比而不是压力比。 |
| Radial engine | 径向发动机 |
A piston engine in which the cylinders are arranged radially around the crankshaft, a design commonly used in early aircraft engines. 气缸沿径向围绕曲轴布置的活塞式发动机，这种设计通常用于早期飞机发动机。 |
| Guided-bend test | 导向弯曲试验 |
A test in which the specimen is bent to a definite shape by means of a punch (mandrel) and a bottom block. 用冲头（心轴）和底块将试样弯曲成一定形状的试验。 |
| Free machining | 易切削 |
The property that makes machining easy because of the forming of small chips, a characteristic imparted to steel by sulfur, etc. 由于形成小切屑而使加工变得容易的特性，比如硫赋予钢的特性，等等。 |
| Taper key | 楔键 |
A key with parallel sides but tapering cross section along its length. 边平行但横截面沿其长度逐渐变细的键。 |
| Dilatometer | 膨胀计 |
An instrument for measuring length or volume changes in a solid during heating and subsequent cooling or isothermal holding. · An instrument for measuring the linear expansion or contraction in a metal resulting from changes in such factors as temperature and allotropy. 一种在加热和随后的冷却或等温保持过程中测量固体长度或体积变化，测量金属因温度和同素异形体等因素的变化而引起的线性膨胀或收缩的仪器。 |
| 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。 |
| Proportional limit | 比例极限 |
The greatest stress a material is capable of developing without a deviation from straight-line proportionality between stress and strain. 材料能够产生的最大应力不偏离应力和应变之间的直线比例。 |
| 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。 |
| 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。 |
| Fastener with reduced shank | 短柄紧固件 |
Finished fastener with a shank diameter of ds ≈ d2. 柄径为ds≈d2的紧固件。 |
| Stress area | 应力面积 |
The effective cross-sectional area of the threaded section of a fastener. Used to compute average stress levels in that section. Based on the mean of pitch and minor diameters. 紧固件螺纹部分的有效横截面积。用于计算该截面中的平均应力水平。基于节距和小直径的平均值。 |
| 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。 |
| 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。 |
| Corrosive wear | 腐蚀磨损 |
Wear in which chemical or electrochemical reaction with the environment is significant. 与环境发生显着化学或电化学反应的磨损。 |
| 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。 |
| Magnetic materials | 磁性材料 |
Materials in which the magnetic moment of adjacent atoms can adopt either parallel or antiparallel alignment. Ferromagnetism occurs when the magnetic moments adopt parallel alignment. When adjacent magnetic moments cancel due to antiparallel alignment, the material exhibits antiferromagnetism and has no overall magnetic moment. Examples of the latter include ferrous oxide and manganese oxide. The phenomenon of ferrimagnetism occurs when adjacent magnetic moments adopt antiparallel alignment but have unequal magnitude. The region of ferromagnetic or ferrimagnetic material in which the magnetic moments are aligned is known as a magnetic domain and adjacent regions are separated by domain walls. Diamagnetic and paramagnetic materials exhibit weak forms of magnetism that results from independent (uncoupled) alignment of magnetic atomic dipoles induced by an applied magnetic field. Ferromagnetic and ferrimagnetic materials can acquire high degrees of magnetization in relatively weak magnetic fields. They have different hysteresis characteristics and are classified as either hard magnets or soft magnets. Hard magnets retain large magnetization in the absence of an applied magnetic field and are used as permanent magnets. Conventional materials include magnet steels alloyed with tungsten or cobalt. Rare-earth magnets made from alloys of rare-earth elements produce significantly stronger magnetic fields. The most common of these are samarium-cobalt and neodymiumiron-boron permanent magnets. Their strength allows them to be small and used in numerous applications, including cordless tools, disk drives, headphones, toys, and motors for automotive components such as wipers, fans, washers, and windows. Soft magnets may be magnetized and demagnetized relatively easily. When subjected to an alternating magnetic field the energy loss due to hysteresis is small. Common materials include iron-silicon alloys (known as electrical steels), nickel-iron alloys (permalloy), soft ferrites, and amorphous nanocrystalline alloys, the last of which can be produced in the form of tape by meltspinning. Soft magnets are used to enhance the magnetic flux produced by an electric current. 相邻原子的磁矩可以采用平行或反平行排列的材料。当磁矩采用平行排列时，会产生铁磁性。当相邻磁矩因反平行排列而抵消时，材料表现出反铁磁性，没有总磁矩。后者的实例包括氧化亚铁和氧化锰。当相邻磁矩采用反平行排列但大小不等时，就会出现铁磁现象。磁矩对齐的铁磁或铁磁材料区域称为磁畴，相邻区域由磁畴壁分隔。抗磁和顺磁材料表现出弱磁性形式，这是由外加磁场诱导的磁原子偶极子的独立（非耦合）排列引起的。铁磁性和铁磁性材料可以在相对弱的磁场中获得高磁化度。它们具有不同的磁滞特性，分为硬磁铁和软磁铁。硬磁铁在没有外加磁场的情况下保持较大的磁化强度，用作永磁体。常规材料包括与钨或钴合金化的磁钢。由稀土元素合金制成的稀土磁体产生明显更强的磁场。其中最常见的是钐钴和钕硼永磁体。它们的强度使其体积小，可用于多种应用，包括无绳工具、磁盘驱动器、耳机、玩具和汽车部件（如雨刷、风扇、洗衣机和车窗）的电机。软磁体可以相对容易地磁化和退磁。当受到交变磁场时，由于磁滞引起的能量损失很小。常见材料包括铁硅合金（称为电工钢）、镍铁合金（坡莫合金）、软铁氧体和非晶纳米晶合金，最后一种可以通过熔钉以胶带的形式生产。软磁铁用于增强电流产生的磁通量。 |
| Stress corrosion | 应力腐蚀 |
(stress-corrosion cracking) Corrosion failure accelerated by local stresses (particularly tensile) which enhance cracking in both monotonic and fatigue loading. （应力腐蚀开裂）局部应力（特别是拉伸应力）加速的腐蚀失效，该局部应力在单调载荷和疲劳载荷下都会增强开裂。 |
| Ferritic stainless steels | 铁素体不锈钢 |
Ferritic stainless steels have the ferrite (BCC) crystal structure and contain 10–28% chromium and typically 0.1–0.35% carbon (all in wt%). They are magnetic and can be hardened by cold working. They have good to moderate mechanical properties, good oxidation and corrosion resistance at elevated temperatures, and susceptibility to embrittlement at temperatures between 400 and 540°C. Used for turbine parts, hightemperature valves, automotive exhaust components, and nuclear reactor core components. 铁素体不锈钢具有铁素体（BCC）晶体结构，含有10-28%的铬，通常含有0.1-0.35%的碳（均为重量%）。它们具有磁性，可通过冷加工硬化。它们具有良好至中等的机械性能，在高温下具有良好的抗氧化性和耐腐蚀性，在400至540°C的温度下易脆化。用于涡轮零件、高温阀、汽车排气部件和核反应堆堆芯部件。 |
| Transfer machines | 转印机 |
These specialized machine tools are used to perform various machining operations on parts or parts in fixtures as the parts are moved along on an automatic conveyor which is part of the machine tool set-up. In a set-up, the parts can move in a straight line from their entry point to their exit point, or the setup may be constructed in a U-shape so that the parts are expelled near where they start. 当零件在自动输送机上移动时，这些专用机床用于对零件或夹具中的零件执行各种加工操作，自动输送机是机床设置的一部分。在设置中，零件可以从其入口点直线移动到其出口点，或者设置可以构造为U形，以便零件在其起点附近排出。 |
| Decompression chamber | 减压舱 |
A chamber in which ambient-air pressure can be increased to levels found in deep-sea diving. It is used to gradually acclimatize divers back to normal conditions and avoid ‘the bends’. 环境气压可以提高到深海潜水水平的腔室。它用于逐渐使潜水员适应正常条件，避免“弯曲”。 |
| Notch brittleness | 缺口脆性 |
Susceptibility of a material to brittle fractureat points of stress concentration. For example, in a notch tensile test, the material is said to be notch brittle if the notch strengthis less than the tensile strength of an unnotched specimen. Otherwise, it is said to be notch ductile. 材料在应力集中点易发生脆性断裂。例如，在缺口拉伸试验中，如果缺口强度小于无缺口试样的抗拉强度，则称材料为缺口脆性材料。否则，称其为缺口韧性。 |
| Gasket factors | 垫片系数 |
Experimentally derived ‘‘constants’’ used to define the behavior of a gasket or the assembly and in-service conditions required for acceptable behavior. 实验得出的“常数”用于定义垫圈的行为或可接受行为所需的组件和使用条件。 |
| 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。 |
| Mechanical properties of solid materials | 固体材料的力学性能 |
The strength and stiffness properties of solid materials such as fracture toughness, the moduli of elasticity, percent elongation, 固体材料的强度和刚度特性，例如断裂韧性、弹性模量、伸长率、 |
| Hydrogen embrittlement | 氢脆 |
A condition of low toughness, low ductility or cracking in metals resulting from the absorption of hydrogen. A common and troublesome form of Stress cracking. Several theories have been proposed to explain hydrogen embrittlement, but, at present, the exact mechanism is still unknown. What is known, however, is the fact that if hydrogen is trapped in a bolt by poor electroplating practices, it can encourage stress cracking. Bolts can fail, suddenly and unexpectedly, under normal loads. Premature crack growth over time under tensile stress leading to unexpected failure in certain metals, caused by small amounts of hydrogen in the microstructure. Hydrogen may enter steels during melting or heat treating, or during processes such as electroplating. 因吸收氢而导致金属韧性低、延展性低或开裂的情况，是一种常见且麻烦的应力开裂形式。在拉伸应力下，裂纹随时间过早扩展，导致某些金属发生意外失效，这是由微观结构中的少量氢引起的。在熔化或热处理过程中，或在电镀等过程中，氢可能进入钢中。已经提出了几种理论来解释氢脆，但目前，确切的机理仍然未知。已知的事实是，如果氢因电镀不当而被困在螺栓中，则会导致应力开裂。在正常载荷下，螺栓可能突然意外失效。 |
| Microhardness | 显微硬度 |
The hardness of a material as determined by forcing an indenter such as a Vickers or Knoop indenter into the surface of a material under very light load; usually, the indentations are so small that they must be measured with a microscope. Capable of determining hardnesses of different microconstituents within a structure, or of measuring steep hardness gradients such as those encountered in case hardening. 通过在非常轻的载荷下将压头（如维氏或努氏压头）压入材料表面来确定的材料硬度；通常压痕很小，必须用显微镜测量。能够确定结构内不同微组分的硬度，或测量陡峭的硬度梯度，如表面硬化中遇到的硬度梯度。 |
| Coupling | 耦合 |
A detachable mechanism forming a joint. A connector of two components of a joint. 1. Any mechanical fastening connecting two or more shafts, or parts of a mechanism, in order to transmit power. 2. A device for connecting two vehicles. 一种形成关节的可拆卸机构。关节的两个组件的连接器。1.连接两个或多个轴或机构部件的任何机械紧固件，以传递动力。2.连接两辆车的装置。 |
| Annealing twin | 退火孪晶 |
A twin form in a crystal during recrystallization. 重结晶过程中晶体中的孪晶形式。 |
| Least count | 最小计数 |
The smallest value that can be read from an instrument having a graduated scale. Except on instruments provided with a vernier, the least count is that fraction of the smallest division which can be conveniently and reliably estimated; this fraction is ordinarily one-fifth or one-tenth, except where the graduations are very closely spaced. 可从具有刻度尺的仪器中读取的最小值。除配备游标的仪器外，最小计数是可以方便可靠地估计的最小除法的分数；这个分数通常是五分之一或十分之一，除非刻度间隔非常近。 |
| Strength of bolt | 螺栓强度 |
An ambiguous term which can mean Ultimate strength or Proof load or Endurance limit or Yield strength. 一个模棱两可的术语，可表示极限强度或验证荷载或耐久极限或屈服强度。 |
| Turning angle (θ) | 转向角（θ） |
The change in direction experienced by a gas flow passing through an oblique shock wave or Prandtl–Meyer expansion fan. 气流通过斜激波或Prandtl–Meyer膨胀风机时所经历的方向变化。 |
| Reverse engineering | 逆向工程 |
The disassembly of a machine, mechanism, system or device, measurement of its component parts, and identification of the materials used so that if required, a functioning replica can be produced. 拆卸机器、机构、系统或装置，测量其组成部分，并识别所用材料，以便在需要时可以生产出功能正常的复制品。 |
| Wrinkling | 起皱 |
A wavy condition obtained in deep drawing of sheet metal, in the area of the metal between the edge of the flange and the draw radius. Wrinkling may also occur in other forming operations when unbalanced compressive forces are set up. 在金属板深冲过程中，在法兰边缘和拉深半径之间的金属区域内获得的波浪状状态。当设置不平衡压缩力时，在其他成形操作中也可能发生起皱。 |
| Shear test | 剪切试验 |
Any of several tests to obtain shear strength of a metal. Common tests used on mill products include the double-shear test, single-shear test, the blanking shear test (also known as the punching shear test) and the torsion test. 获得金属剪切强度的几种测试中的任何一种。轧机产品上常用的试验包括双剪试验、单剪试验、落料剪切试验（也称为冲切试验）和扭转试验。 |
| 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。 |
| Right hand thread | 右旋螺纹 |
A screw thread which advances into the mating part when turned clockwise or to the right. 顺时针或向右转动时进入配合部件的螺纹。 |
| Mode of failure | 故障模式 |
The various ways in which a material can fail when subjected to loading, surface damage, chemical attack, heating, cooling, or radiation, in either isolation or combination. The failure modes include fracture, fatigue, creep, corrosion, erosion, and embrittlement. 材料在受到载荷、表面损伤、化学侵蚀、加热、冷却或辐射时，可能发生失效的各种方式，无论是单独还是组合。失效模式包括断裂、疲劳、蠕变、腐蚀、侵蚀和脆化。 |
| Temporal decomposition | 时间分解 |
The splitting of a control problem into parts with relatively short and long time constant so that different controllers may be used for the different parts. 将控制问题分解为具有相对较短和较长时间常数的部分，以便不同的部分可以使用不同的控制器。 |
| 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。 |
| Induction hardening | 感应淬火 |
A surface-hardening process in which only the surface layer of a suitable ferrous workpiece is heated by electromagnetic induction to above the upper critical temperature and immediately quenched. 一种表面硬化工艺，在该工艺中，只有合适的含铁工件的表面层通过电磁感应加热到高于上临界温度，并立即淬火。 |
| 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。 |
| Compressor bleed | 压缩机排气 |
The removal of air before the final stage of a multistage compressor operating below design speed, to prevent the final stage from choking. 在低于设计速度运行的多级压缩机的末级之前去除空气，以防止末级阻塞。 |
| Ductile | 延展性材料 |
(ductile material) Describes a material that can be deformed permanently to large strains without fracture. If a bolt can be stretched well past its yield point before breaking, it is said to be ductile. （延展性材料）描述一种可以永久变形到大应变而不断裂的材料。如果螺栓在断裂前可以很好地拉伸超过其屈服点，则称其具有延展性。 |
| Absorption | 吸收 |
The process whereby a fluid permeates a porous solid, or a gas is dissolved by a liquid. 流体渗透多孔固体或气体被液体溶解的过程。 |
| Stretch ratio (extension ratio, λ) | 拉伸比（拉伸比，λ） |
A measure, used for highly-extensible materials such as rubber, of the extensional or normal strain of a component subjected to tension and defined as the ratio of the final length l, for a given load, to the initial or gauge length l0, where the coordinate axes are those of principal strain. It is related to the engineering strain e by λ = 1 + e. 用于高度可延展材料（如橡胶）的一种测量方法，用于测量受拉构件的拉伸或法向应变，定义为给定载荷下的最终长度l与初始或标距长度l0之比，其中坐标轴为主应变轴。它与工程应变e的关系为λ=1+e。 |
| Proof strength (Unit Pa) | 验证强度（单位Pa） |
(proof stress, Rp, Rp,) The yield strength (offset yield strength) at some fixed value of the permanent strain given by the intersection of a line offset from, but parallel to, the elastic loading line and the engineering stress-engineering strain curve. The offset is arbitrary but is usually 0.1, 0.2, or 0.5% permanent strain (the proof strain). Used for materials which do not exhibit a sharply defined yield point. The notation Rp0.2 or Rp0.2 is employed for the 0.2% proof stress. （验证应力，Rp）在永久应变的某个固定值下的屈服强度（偏移屈服强度），由偏离但平行于弹性加载线的线与工程应力-工程应变曲线的交点给出。偏移是任意的，但通常为0.1、0.2或0.5%的永久应变（验证应变）。用于没有明确定义屈服点的材料。对于0.2%的验证应力，采用符号Rp0.2。 |
| Carbonitriding | 碳氮共渗 |
A case hardening process in which a suitable ferrous material is heated above the lower transformation temperature in a gaseous atmosphere of such composition as to cause simultaneous absorption of carbon and nitrogen by the surface and, by diffusion, create a concentration gradient. The process is completed by cooling at a rate that produces the desired properties in the workpiece. 一种表面硬化工艺，在该工艺中，将合适的含铁材料在气体气氛中加热到较低的转变温度以上，使其表面同时吸收碳和氮，并通过扩散形成浓度梯度。该工艺通过以在工件中产生所需性能的速率冷却来完成。 |
| Slant fracture | 倾斜裂缝 |
A type of fracture appearance, typical of plane-stress fractures, in which the plane of metal separation is inclined at an angle (usually about 45°) to the axis of the applied stress. 一种断裂现象，典型的平面应力断裂，其中金属分离面与施加应力的轴成一定角度（通常约45°）倾斜。 |
| 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。 |
| 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。 |
| Creep | 蠕变 |
The slow, plastic deformation of a body under heavy loads. Time-dependent plasticity. Time-dependent and permanent deformation of material under constant load or stress. The strain increases with time at a rate that increases with increasing temperature. Creep can lead to large strain and eventual failure, and so limit the lifetime of components subjected to load at high temperature. Creep in metals becomes significant at homologous temperatures in excess of about 0.4, e.g. 1200°C for tungsten, 504°C for titanium, 450°C for iron, and 100°C for aluminium. 物体在重载荷下缓慢的塑性变形，随时间变化的可塑性，材料在恒定载荷或应力下随时间变化的永久变形。应变随时间以随温度升高而增加的速率增加。蠕变可能导致大应变和最终失效，从而限制部件在高温下承受载荷的寿命。当同源温度超过约0.4℃时，金属蠕变变得显著，例如钨为1200℃，钛为504℃，铁为450℃，铝为100℃。 |
| Friction materials | 摩擦材料 |
Materials having a high coefficient of friction which, when coupled with a long life, may be employed as brake linings or the facing of the plates of a clutch. 具有高摩擦系数的材料，当与长寿命相结合时，可用作制动衬片或离合器片的饰面。 |
| Grain | 晶粒 |
1. An individual crystal in a polycrystalline solid. Most engineering materials such as metals and ceramics are used in polycrystalline form. 2. (gr) A non-SI unit of mass. The conversion to SI is 1 gr = 6.479 891 × 10−5 kg. 1.多晶固体中的单个晶体。大多数工程材料，如金属和陶瓷，都以多晶形式使用。2.（gr）非国际单位制的质量单位。转换为SI为1gr=6.479891×10-5kg。 |
| Bolt blank | 螺栓毛坯 |
A rod on which a head has been formed, but on which no thread has been cut, from which bolts or screws may be made as required. 一种已形成头部但未切割螺纹的杆，可根据需要从中制造螺栓或螺钉。 |
| Screw displacement | 螺杆位移 |
A rotation of a rigid body about an axis accompanied by a translation of the body along the same axis. 刚体绕轴旋转，同时刚体沿同一轴平移。 |
| 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。 |
| 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。 |
| Radioactive heat (Unit J) | 放射性热（单位J） |
Thermal energy released from the nucleus of an atom such as uranium235 by fission due to the absorption of a neutron. Heat is also produced by radioactive decay. 铀235等原子核因吸收中子而裂变释放的热能。放射性衰变也会产生热量。 |
| Natural unit system (n.u. system) | 自然单位制（n.u.制） |
A non-SI system of units, based on fundamental constants, used in high-energy and particle physics. The n.u. of speed is the speed of light in a vacuum, c0 = 299 792 458 m/s. 基于基本常数的非国际单位制，用于高能和粒子物理n.u.速度是真空中的光速，c0=299792458m/s。 |
| Sampling | 抽样 |
The process of measuring a series of values of a time-varying quantity. 测量一系列时变量值的过程。 |
| Olsen cup test | 奥尔森杯测试 |
A cupping test in which a piece of sheet metal, restrained except at the center, is deformed by a standard steel ball until fracture occurs. The height of the cup at time of fracture is a measure of the ductility. 一种杯突试验，其中一块金属板，除了中心以外，被一个标准钢球变形，直到发生断裂。断裂时杯的高度是延展性的量度。 |
| Caustic cracking | 苛性开裂 |
A form of stress-corrosion cracking most frequently encountered in carbon steels or iron-chromiumnickel alloys that are exposed to concentrated hydroxide solutions at temperatures of 200 to 250 °C (400 to 480 °F). Also known as caustic embrittlement. 在200至250°C（400至480°F）的温度下暴露于浓氢氧化物溶液中的碳钢或铁铬镍合金中最常遇到的一种应力腐蚀开裂形式。也称为碱脆。 |
| Coefficient of rolling friction | 滚动摩擦系数 |
The ratio of force parallel to a surface, on which an object rolls, to the normal force. Unlike sliding friction, rolling friction depends on the size of the contact patch and the radius of the rolling element, and the behaviour depends on whether the contact is elastic, viscoelastic, or plastic and on hysteresis losses. 平行于物体滚动表面的力与法向力之比。与滑动摩擦不同，滚动摩擦取决于接触片的大小和滚动元件的半径，其行为取决于接触是弹性的、粘弹性的还是塑性的以及滞后损失。 |
| Sample standard deviation (s) | 样本标准偏差（s） |
The square root of the sample variance. It is a point estimate of the population standard deviation, a measure of the “spread”of the frequency distribution of a population. This value of sprovides a statistic that is used in computing interval estimates and several test statistics. For small sample sizes, s underestimates the population standard deviation. 样本方差的平方根。它是总体标准偏差的点估计，是总体频率分布“扩散”的度量。SPR的这个值提供了一个用于计算区间估计和若干测试统计量的统计量。对于小样本，s低估了总体标准偏差。 |
| Balancing machine | 平衡机 |
A device that assesses the state of static and dynamic balance of a rotating part, and indicates the magnitude and location of weights to be added to give balance. 一种装置，用于评估旋转部件的静态和动态平衡状态，并指示为获得平衡而添加的砝码的大小和位置。 |
| 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。 |
| Transformation temperature | 相变温度 |
The temperature at which a change in phase occurs. The term is sometimes used to denote the limiting temperature of a transformation range. The following symbols are used for iron and steels. 发生相位变化的温度。该术语有时用于表示转变范围的极限温度。以下符号用于钢铁。 |
| 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。 |
| Clearance angle | 后角 |
(relief angle) (Unit °) The angle between the underneath or flank of a cutting tool and the machined surface. （后角）（单位°）切削刀具的底部或侧面与加工表面之间的角度。 |
| 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）。 |
| Critical point | 临界点 |
(1) The temperature or pressure at which a change in crystal structure, phase or physical properties occurs. Same as transformation temperature. (2) In an equilibrium diagram, that specific value of composition, temperature and pressure, or combinations thereof, at which the phases of a heterogeneous system are in equilibrium. （1） 晶体结构、相或物理性质发生变化的温度或压力。与转变温度相同。（2） 在平衡图中，指组成、温度和压力或其组合的特定值，在该值下，多相体系的相处于平衡状态。 |
| Flame annealing | 火焰退火 |
Annealing in which the heat is applied directly by a flame. 通过火焰直接加热的退火。 |
| 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。 |
| Achme thread | Achme螺纹 |
A screw thread having an included angle of 29° and largely used for feed screws on machine tools. 一种夹角为29°的螺纹，主要用于机床上的进给丝杠。 |
| Imperial system | 英制单位体系 |
The units of measurement developed in the UK. Formerly known as the fps system, which is an abbreviation for the ‘foot-pound-second system of units. 英国开发的计量单位。以前称为fps系统，是“英尺-磅-秒（foot-pound-second）单位制”的缩写。 |
| Torque meter | 扭矩计 |
An instrument for measuring torque using spring-loaded, piezoelectric, or strain-gauged devices. 使用弹簧加载、压电或应变测量装置测量扭矩的仪器。 |
| Thread run-out | 螺纹耗尽 |
That portion of the threads which are not cut or rolled full depth, but which provide the transition between full-depth threads and the body or head. Officially called thread washout or vanish, although the term run-out is more popular. (Run-out is officially reserved for rotational eccentricity, as defined by total indicator readings or the like.) 未全深度切割或轧制的螺纹部分，但提供全深度螺纹与主体或头部之间的过渡。官方称之为螺纹冲蚀或消失，但术语“耗尽”更为流行。（跳动是官方为旋转偏心度保留的，由总指示器读数等定义。） |
| 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。 |
| Impact test | 碰撞测试 |
A test for determining the energy absorbed in fracturing a test piece at high velocity, as distinct from static test. The test may be carried out in tension, bending, or torsion, and the test bar may be notched or unnotched. 测定试件在高速下破裂时吸收的能量的试验，与静态试验不同。测试可以在拉伸、弯曲或扭转条件下进行，测试杆可以有缺口或无缺口。 |
| 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。 |
| 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。 |
| Vernier | 游标 |
A short auxiliary scale that slides along the main instrument scale to permit more accurate fractional reading of the least main division of the main scale. 一种短辅助刻度，沿主仪表刻度滑动，以便更准确地读取主刻度的最小主刻度。 |
| Octane number | 辛烷值 |
(octane rating) A measure of the anti-knock properties of a fuel taken as the percentage by volume of iso-octane in the fuel. （辛烷值）以燃料中异辛烷的体积百分比表示的燃料抗爆性能的量度。 |
| Critical cooling rate | 临界冷却速度 |
The rate of continuous cooling required to prevent undesirable transformation. For steel, it is the minimum rate at which austenite must be continuously cooled to suppress transformations above the Ms temperature. 防止不期望的转变所需的连续冷却速率。对于钢，它是奥氏体必须持续冷却以抑制Ms温度以上的转变的最小速率。 |
| 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。 |
| 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。 |
| Actual cubic feet per minute | 实际立方英尺每分钟 |
(acfm) An obsolete (i.e. non-SI) measure of volumetric flow rate; the volume of a gas flowing per minute at actual operating pressure and temperature, as opposed to the corresponding volume flow rate at STP. （acfm）已被淘汰的（即非SI）体积流量测量；在实际工作压力和温度下每分钟流动的气体体积，与STP下的相应体积流量相反。 |
| Slot | 狭槽 |
A groove machined into a component, e.g. to allow for thermal expansion, or in which the tongue or tip of another component can fit or slide. 在部件上加工的凹槽，例如，允许热膨胀，或另一部件的榫舌或尖端可在其中安装或滑动。 |
| Friction loss (Unit J) | 摩擦损失（单位J） |
The conversion of mechanical energy to heat due to friction within a machine, mechanism, linkage, etc. 由于机器、机构、连杆等内部的摩擦而将机械能转化为热能。 |
| Crank angle (Unit °) | 曲柄角度（单位°） |
The angle between the crank of a slider-crank mechanism and a line from the crankshaft centreline to the piston axis. 曲柄滑块机构的曲柄与曲轴中心线到活塞轴线的直线之间的角度。 |
| 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）。 |
| Zone melting (zone refining) | 区域熔炼（区域精炼） |
A process of purification of materials in which a narrow molten zone is moved along the length of the material, resulting in impurities being segregated at one end. 一种净化材料的过程，其中一个狭窄的熔融区沿材料长度移动，导致杂质在一端分离。 |
| Residual stress (Unit Pa) | 残余应力（单位Pa） |
Stresses that remain within a body as the result of thermal or mechanical treatment or both. (internal stress) An internal-stress system found in components that have experienced elastic unloading from non-uniform plastic-strain fields during manufacture. 由于热处理或机械处理或两者兼而有之而留在物体内的应力。（内应力）在制造期间从非均匀塑性应变场经历弹性卸载的部件中发现的内应力系统。 |
| High strength low alloy steels | 高强度低合金钢 |
(HSLA steels) Steels with various micro-alloying elements such as copper, nickel, chromium, molybdenum, niobium, titanium, and vanadium in small quantities that give improved strength (as high as 900 MPa) and corrosion properties compared with plain carbon steels. Improvements are due to grain refinement and precipitation hardening, better control of the chemistry during steel making, and accurate rolling temperatures. （HSLA钢）是含有各种微合金元素的钢，如少量的铜、镍、铬、钼、铌、钛和钒，与普通碳钢相比，具有更好的强度（高达900MPa）和腐蚀性能。这些改进归功于晶粒细化和沉淀硬化、炼钢过程中更好的化学控制以及精确的轧制温度。 |
| Initial stress | 初始应力 |
The stress produced by strain in a specimen immediately on achieving the given constant-strain conditions in a stress-relaxation test before stress-relaxation occurs. Sometimes referred to as instantaneous stress. 在应力松弛发生之前，在应力松弛试验中达到给定的恒定应变条件时，试样立即应变所产生的应力。有时称为瞬时压力。 |
| Batch | 一批 |
A definite quantity of some product or material produced under conditions that are considered uniform. A batch is usually smaller than a lot. 在被认为是均匀的条件下生产的一定数量的某些产品或材料。批次通常小于很多。 |
| Crest | 波峰 |
The highest point of a wave or of a screw thread. 波浪或螺纹的最高点。 |
| Turbine flow meter | 涡轮流量计 |
(axial flow meter, propeller meter) An in-line flow meter in which the rotation speed N of a propeller or rotor is a measure of the mass flowrate ṁ. Calibration is always necessary but with appropriate design ṁ is closely proportional to N over a wide range. （轴向流量计、螺旋桨流量计）一种串联流量计，其中螺旋桨或转子的转速N是质量流量的测量值ṁ. 校准总是必要的，但需要适当的设计ṁ在很宽的范围内与N成正比。 |
| Mass flow rate (ṁ) (Unit kg/s) | 质量流量（ṁ）（单位kg/s） |
The mass of a material, usually a fluid or powder, that flows across a surface or through a pipe or other duct per unit time. The corresponding mass flux (ṁ″), with unit kg/s.m², is the mass flow across a real surface or through a duct, divided by the surface or cross-sectional area A, i.e. ṁ″ = ṁ/A or ṁ″ = ρV where ρ is the material density and V is its velocity normal to the surface. 单位时间内流过表面或通过管道或其他管道的材料质量，通常是流体或粉末。相应的质量通量（ṁ″），单位为kg/s.m²，是通过真实表面或通过管道的质量流量除以表面或横截面积A，即ṁ″=ṁ/A或ṁ″=ρV，其中ρ是材料密度，V是其垂直于表面的速度。 |
| Stress factor | 应力因子 |
A calibration constant used in ultrasonic measurement of bolt stress or strain. It is the ratio between the change in ultrasonic transit time caused by the change in length of the fastener, under load, to the total change in transit time. 用于螺栓应力或应变超声波测量的校准常数。它是由紧固件长度变化引起的超声波传输时间变化与总传输时间变化之间的比率。 |
| 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。 |
| 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。 |
| Coil spring | 螺旋弹簧 |
A spiral (‘clockwork’) or helical (cylindrical) spring. A spring steel wire wound in a spiral pattern. 螺旋（“发条”）或螺旋（圆柱形）弹簧。以螺旋状缠绕的弹簧钢丝。 |
| 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。 |
| Checks | 检查 |
Numerous, very fine cracks in a coating or at the surface of a metal part. Checks may appear during processing or during service and are most often associated with thermal treatment or thermal cycling. 涂层中或金属零件表面的许多非常细微的裂纹。在加工或服务期间可能会出现检查，并且通常与热处理或热循环有关。 |
| Hardenability | 淬透性 |
Defined as the ability of a ferrous material to acquire hardness after austenitization and quenching. The relative ability of a ferrous alloy to form martensite when quenched from a temperature above the upper critical temperature. Hardenability is commonly measured as the distance below a quenched surface where the metal exhibits a specific hardness (50 HRC, for example) or a specific percentage of martensite in the microstructure. 定义为黑色金属材料在奥氏体化和淬火后获得硬度的能力。铁合金从高于上临界温度的温度淬火时形成马氏体的相对能力。淬透性通常以淬火表面下方的距离来测量，金属在淬火表面处表现出特定硬度（例如50HRC）或微观结构中马氏体的特定百分比。 |
| Screw compressor | 螺杆压缩机 |
A positive-displacement rotary compressor in which gas is progressively compressed by two intermeshing, counter-rotating, helical screws. 一种容积式旋转压缩机，其中气体由两个相互啮合、反向旋转的螺旋螺杆逐渐压缩。 |
| Tolerance limits | 公差极限 |
The extreme values (upper and lower) that define the range of permissible variation in size or other quality characteristic of a part. 定义零件尺寸或其他质量特性允许偏差范围的极值（上限和下限）。 |
| Crack | 裂缝 |
A thin fissure-like defect in a component or structure across which material continuity is lost and which reduces the strength of the body. 部件或结构中的细裂缝状缺陷，材料连续性丧失并降低了身体的强度。 |
| Shock load | 冲击载荷 |
The sudden application of an external force that results in a very rapid build-up of stress. 突然施加外力，导致应力迅速增加。 |
| Permissible variation | 允许偏差 |
For testing machines, the maximum allowable error in the value of the quantity indicated. It is convenient to express permissible variation in terms of the percent error. 对于试验机，所示数量值的最大允许误差。用误差百分比表示允许偏差是很方便的。 |
| Thermal reactor | 热反应器 |
An enlarged exhaust manifold bolted directly to the cylinder head of a piston engine, in which the oxidation of carbon monoxide and unburned hydrocarbons in the exhaust gas is enhanced. 一种扩大的排气歧管，直接用螺栓固定在活塞式发动机的气缸盖上，其中一氧化碳和未燃烧碳氢化合物的氧化作用增强。 |
| Radius of bend | 弯曲半径 |
The radius of the cylindrical surface of the pin or mandrel that comes in contact with the inside surface of the bend during bending. For free or semiguided bends to 180° in which a shim or block is used, the radius of bend is one-half the thickness of the shim or block. 在弯曲过程中与弯曲内表面接触的销或心轴的圆柱面半径。对于使用垫片或垫块的180°自由弯曲或半导向弯曲，弯曲半径为垫片或垫板厚度的一半。 |
| Alternative energy | 可替代能源 |
(alternate energy) Energy sources that are renewable and do not have the undesired consequences of fossil fuels and nuclear energy. （替代能源）可再生能源，不会产生化石燃料和核能的不良后果。 |
| Allowable stress design | 许用应力设计 |
A design procedure developed for the AISC by the Research Council on Structural Connections. Purposely underestimates the strengths of bolts and joint materials to introduce safety factors into the design of structural steel joints. It is an alternative to the more recently defined load and resistance factor design procedure. 结构连接研究委员会为AISC制定的设计程序。故意低估螺栓和接头材料的强度，以便在结构钢接头的设计中引入安全系数。它是最近定义的荷载和阻力系数设计程序的替代方法。 |
| Auxetic materials | 拉胀材料 |
Those man-made materials for which Poisson’s ratio is negative, so that the cross section expands when subjected to a longitudinal tensile stress and contracts when subjected to a longitudinal compressive stress. 泊松比为负的人造材料，其横截面在受到纵向拉应力时会膨胀，在受到纵向压应力时会收缩。 |
| 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。 |
| 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。 |
| Horizontal batch furnace | 卧式间歇炉 |
A versatile batch-type furnace that can give light or deep case depths, and because the parts are not exposed to air, horizontal batch furnaces can give surfaces almost entirely free of oxides. 一种多功能间歇式炉，可以提供浅或深的外壳深度，并且由于零件不暴露在空气中，卧式间歇式炉可以使表面几乎完全没有氧化物。 |
| T-bolt | T型螺栓 |
A threaded bolt having a square or rectangular end which fits into the T slot of a machine table for clamping workpieces. 一种带有方形或矩形端头的螺栓，可嵌入机床工作台的T形槽中，用于夹紧工件。 |
| Minute (min) | 分钟（min） |
A non-SI unit of time. The conversion to SI is 1 min = 60 s. 非SI时间单位。转换为1分钟=60秒。 |
| Carbonization | 碳化 |
Conversion of an organic substance into elemental carbon. 将有机物质转化为元素碳。 |
| Compression member | 压缩构件 |
A structural component, the major loading on which is compressive. 一种结构部件，其上的主要载荷是压缩的。 |
| Core | 核心 |
In a ferrous alloy prepared for case hardening, that portion of the alloy that is not part of the case . Typically considered to be the portion that (a) appears light on an etched cross section, (b) has an essentially unaltered chemical composition, or (c) has a hardness, after hardening, less than a specified value. 在为表面硬化而制备的铁合金中，合金中不属于表面的那部分。通常被认为是（a）在蚀刻横截面上看起来很轻，（b）化学成分基本不变，或（c）硬化后硬度低于规定值的那部分。 |
| True strain | 真应变 |
(1) The ratio of the change in dimension, resulting from a given load increment, to the magnitude of the dimension immediately prior to applying the load increment. (2) In a body subjected to axial force, the natural logarithm of the ratio of the gage length at the moment of observation to the original gage length. Also known as natural strain. Compare with engineering strain. （1）给定载荷增量导致的尺寸变化与施加载荷增量之前尺寸大小的比率。（2）在承受轴向力的物体中，观察时刻标距与原始标距之比的自然对数。也称为自然应变。与工程应变相比。 |
| 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。 |
| Altitude | 高度 |
(Unit m) Vertical height measured relative to a specified datum such as sea level. （单位m）相对于特定基准（例如海平面）测量的垂直高度。 |
| Shim | 垫片 |
A thin piece of material, such as metal of accurately-known thickness, placed between two surfaces to ensure they are the correct distance apart. A thin piece of material placed between two surfaces to obtain a proper fit, adjustment, or alignment. The piece can also be analyzed to measure furnace carbon potential (that is, because while in the furnace it will quickly carburize to a level equal to the furnace carbon potential). 一块薄的材料，如厚度精确已知的金属，放置在两个表面之间，以确保它们之间的距离正确。放置在两个表面之间以获得适当配合、调整或对齐的一块薄材料。还可以对工件进行分析，以测量熔炉碳势（也就是说，在熔炉中，工件将快速渗碳至与熔炉碳势能相等的水平）。 |
| 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。 |
| Creep fatigue | 蠕变疲劳 |
The effects of combined creep and fatigue at high homologous temperatures in metals, and in other materials such as polymers having time-dependent behaviour. 金属和其他材料（例如具有时间相关行为的聚合物）在高同源温度下的组合蠕变和疲劳的影响。 |
| Pressure (p) (Unit Pa) | 压力（p）（单位Pa） |
In thermodynamics and fluid mechanics, the compressive force exerted by the fluid per unit area. The pressure exerted by a fluid on a surface acts normal to the surface. 在热力学和流体力学中，每单位面积流体施加的压缩力。流体施加在表面上的压力垂直于表面。 |
| Ablation cooling | 烧蚀冷却 |
The cooling of a surface exposed to very high external gas temperature which causes the surface material to sublime, melt or decompose. The chemical process absorbs heat while the mass flow of material away from the surface blocks the heat flux from the hot gas. 冷却暴露于非常高的外部气体温度的表面，导致表面材料升华、熔化或分解。化学过程吸收热量，而远离表面的物质的质量流阻挡了来自热气体的热通量。 |
| Atom | 原子 |
The smallest unit of matter that has the properties of a chemical element. The simplest description of an atom (Bohr model) is of a compact nucleus surrounded by one or more orbiting electrons. 具有化学元素性质的最小物质单位。原子的最简单描述（玻尔模型）是由一个或多个轨道电子包围的致密原子核。 |
| Ratchet coupling | 棘轮联轴器 |
A joint employing a ratchet system between two shafts, so that not only does the driven shaft run in one direction only, but also the driven shaft can, if necessary, run more quickly than the driving shaft. 在两个轴之间采用棘轮系统的接头，这样不仅从动轴只能在一个方向上运行，而且在必要时，从动轴可以比驱动轴运行得更快。 |
| 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。 |
| Intercritical annealing | 临界退火 |
Any annealing treatment that involves heating to, and holding at, a temperature between the upper and lower critical temperatures to obtain partial austenitization, followed by either slow cooling or holding at a temperature below the lower critical temperature. 任何退火处理，包括加热至并保持在上临界温度和下临界温度之间的温度，以获得部分奥氏体化，然后缓慢冷却或保持在低于下临界温度的温度。 |
| 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。 |
| Cast steel | 铸钢 |
Steel that is cast into shapes. It has superior properties to most cast irons, but is more expensive to produce. 铸成形状的钢。与大多数铸铁相比，它具有优越的性能，但生产成本更高。 |
| 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。 |
| Full annealing | 全退火 |
An imprecise term that denotes an annealing cycle to produce minimum strength and hardness. For the term to be meaningful, the composition and starting condition of the material and the time-temperature cycle used must be stated. Annealing a ferrous alloy by austenitizing and then cooling slowly through the transformation range. 一个不精确的术语，表示产生最小强度和硬度的退火循环。为了使该术语有意义，必须说明材料的组成和起始条件以及使用的时间-温度循环。通过奥氏体化退火铁合金，然后在转变范围内缓慢冷却。 |
| Effective length of a bolt | 螺栓的有效长度 |
The grip length plus some portion of the bolt (often one-half of the thickness of the nuts) which lies within the nut(s) plus some portion (often one-half the thickness) of the head. 握持长度加上位于螺母内的螺栓的某些部分（通常是螺母厚度的二分之一）加上头部的某些部分（通常是厚度的二分之一）。 |
| Acoustic power | 声功率 |
(sound power) (Unit W) The rate of flow of acoustic energy across a specified surface. （声功率）（单位W）声能流过指定表面的速率。 |
| Bulk density (Unit kg/m³) | 容重（单位kg/m³） |
The average density of a mass of granular or powdered material at ambient conditions. 在环境条件下大量粒状或粉状材料的平均密度。 |
| Dynamic recovery | 动态恢复 |
A process occurring in hot working of metals in which a fine subgrain structure forms within the elongated grains due to annihilation of dislocations due to easy cross slip and climb. It results in a lowering of the flow stress. Dynamic recovery, as opposed to dynamic recrystallization that occurs in hot working, occurs in metals of high stacking fault energy such as aluminum, αiron, and most bcc metals. 金属热加工中发生的一种过程，由于易于交叉滑动和攀爬，位错湮灭，细长晶粒内形成细亚晶粒结构。这导致流动应力降低。与热加工中发生的动态再结晶相反，动态回复发生在高层错能金属中，如铝、α铁和大多数bcc金属。 |
| Working section | 工作区 |
That part of a wind tunnel in which models are placed for testing, or where detailed measurements are performed. 风洞中放置模型进行测试或进行详细测量的部分。 |
| Scleroscope hardness test | 反跃式硬度试验 |
A dynamic indentation-hardness test using a calibrated instrument that drops a diamond-tipped hammer from a fixed height onto the surface of the material being tested. The height of rebound of the hammer is a measure of the hardness of the material. Also known as Shore hardness test. 使用校准仪器的动态压痕硬度测试，该仪器将金刚石锤从固定高度落在被测材料表面上。锤的回弹高度是材料硬度的一种度量。也称为肖氏硬度测试。 |
| Fatigue | 疲劳 |
The phenomenon leading to fracture under repeated or fluctuating stresses having a maximum value less than the ultimate tensile strength of the material. Fatigue failure generally occurs at loads that, applied statically, would produce little perceptible effect. Fatigue fractures are progressive, beginning as minute cracks that grow under the action of the fluctuating stress. A term referring, in components and structures subjected to either random or cyclic periodically-varying loads, to a progressive reduction in strength leading to failure at stresses lower than those that cause failure under monotonic loading. Variable loads arise from outof-balance machinery and other vibration sources, wind gusts, etc., and a large proportion of service failures is caused by fatigue. Fatigue results from the initiation and slow propagation of cracks. In manufactured components, crack initiation usually occurs at a point of stress concentration. After a period, often of millions of stress cycles, the crack reaches a critical length at which the next peak load causes sudden brittle or ductile fracture. Fracture surfaces resulting from fatigue display characteristic striations or progression marks emanating from the crack initiation site during the slow crack growth period, with a different surface appearance for the final fracture. 在最大值小于材料极限抗拉强度的重复或波动应力下导致断裂的现象。疲劳失效通常发生在静态施加的载荷下，不会产生明显影响。疲劳断裂是渐进性的，从在波动应力作用下生长的微小裂纹开始。在承受随机或周期性变化载荷的部件和结构中，指强度逐渐降低，导致在低于单调载荷下导致失效的应力下发生失效的术语。可变负载由失衡的机械和其他振动源、阵风等引起，大部分故障是由疲劳引起的。疲劳是裂纹萌生和缓慢扩展的结果。在制造部件中，裂纹萌生通常发生在应力集中点。在一段时间（通常是数百万次应力循环）后，裂纹达到临界长度，此时下一个峰值载荷会导致突然脆性或韧性断裂。疲劳产生的断裂表面在缓慢裂纹扩展期间显示出从裂纹萌生部位发出的特征条纹或进展标记，最终断裂的表面外观不同。 |
| Initial preload | 初始预载 |
The tension created in a single bolt as it is tightened. Will usually be modified by subsequent assembly operations or by in-service loads and conditions. 拧紧单个螺栓时产生的张力。通常会通过后续的装配操作或在役负载和条件进行修改。 |
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