| 词或词组 | 中文 | 英文解释中文解释 |
|---|---|---|
| Root diameter (Unit m) | 根部直径（单位：m） |
The diameter of the circle passing through the roots of teeth in gear teeth or screw threads. 穿过齿轮齿或螺纹中齿根的圆的直径。 |
| 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。 |
| Water column | 水柱 |
Water in a tube, which may be vertical or inclined. If the tube is open to the atmosphere, the vertical height h from a datum level to the water surface is a measure of the water static pressure p at the datum level given by p − B = ρgh where B is the barometric pressure, ρ denotes the water density, and g is the acceleration due to gravity. 管道中的水，可以是垂直的或倾斜的。如果管道向大气开放，则从基准面到水面的垂直高度h是基准面处水静压p的量度，由p给出−B=ρgh，其中B是大气压力，ρ表示水密度，g是重力引起的加速度。 |
| Engine emissions | 发动机排放 |
(exhaust emissions) The pollutants contained in the exhaust gases from an internal-combustion engine. （废气排放）内燃机废气中所含的污染物。 |
| Box annealing | 箱式退火 |
Annealing a metal or alloy in a sealed container under conditions that minimize oxidation. In box annealing a ferrous alloy, the charge is usually heated slowly to a temperature below the transformation range, but sometimes above or within it, and is then cooled slowly; this process is also called close annealing or pot annealing. 在使氧化最小化的条件下，在密封容器中对金属或合金进行退火。在对铁合金进行箱式退火时，通常将装料缓慢加热至低于转变范围的温度，但有时会高于或低于转变范围，然后缓慢冷却；这个过程也称为紧密退火或罐式退火。 |
| 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。 |
| Pump | 泵 |
A machine designed to cause a liquid, gas, vapour, or slurry to flow due to the reciprocating motion of pistons, rotation of vanes, or rotation of an impeller. 通过活塞的往复运动、叶片的旋转或叶轮的旋转而使液体、气体、蒸汽或泥浆流动的机器。 |
| Band clutch | 带式离合器 |
A friction clutch in which drive is achieved by a band contracting on to the rim of the clutch. 一种摩擦离合器，其驱动是通过一条带在离合器边缘上收缩来实现的。 |
| 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。 |
| Conduit | 导管 |
A hollow object, of metal, plastic, glass, ceramic, etc., which is relatively long compared with its lateral dimensions and through which there is fluid flow. 由金属、塑料、玻璃、陶瓷等制成的中空物体，与其横向尺寸相比相对较长，并且有流体流过。 |
| 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。 |
| Fracture test | 断裂试验 |
A test in which a specimen is broken and its fracture surface is examined with the unaided eye or with a low-power microscope to determine such factors as composition, grain size, case depth, or internal discontinuities. 1. The recording of load-deflexion (or stress–strain) in a specimen loaded monotonically until it breaks in tension, compression, shear, or torsion. 2. In fatigue, determination of the number of cycles to fracture for a specimen under different patterns of repeated loading. 3. Experiments to determine fracture toughness. 一种试验，其中试样被破坏并用肉眼或低倍显微镜检查其断裂表面，以确定成分、晶粒尺寸、表层深度或内部不连续性等因素。1.记录单调加载试样的载荷偏转（或应力-应变），直到其在拉伸、压缩、剪切或扭转中断裂。2.在疲劳技术中，确定试样在不同重复载荷模式下的断裂循环次数。3.测定断裂韧性的实验。 |
| Damage tolerance | 损伤容限 |
(defect tolerance) A design philosophy that takes into account initial imperfections, crack-growth rates and conditions at final fracture, and uses fracture mechanics to demonstrate that cracks should not grow to their critical length within the design life (or at least should be capable of ready detection). （缺陷公差）考虑初始缺陷、裂纹扩展速率和最终断裂条件的设计理念，并使用断裂力学证明裂纹不应在设计寿命内增长到其临界长度（或至少应能够随时检测）。 |
| 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。 |
| Torque arm | 扭力臂 |
A bar fixed at one end used to resist torque applied at the other, for example by an electric drill. 固定在一端的杆，用于抵抗施加在另一端的扭矩，如电钻。 |
| Ackerman linkage | 阿克曼装置 |
A steering linkage on a motor vehicle that approximately gives rolling without slipping of both wheels about the turning point. This is achieved by having the inner stub axle (on the inside of the turning curve) move through a greater angle than the outer stub axle. 机动车辆上的一种转向联动装置，在转向点附近两个车轮几乎不会打滑。这是通过使内短轴（在转弯曲线的内侧）比外短轴移动更大的角度来实现的。 |
| A-basis | A-基础 |
Mechanical property value above which at least 99% of the population of values is expected to fall, with a confidence of 95%. Also called A-allowable. 机械性能值超过该值时，至少99%的值预计会下降，置信度为95%。也被称为A-容许。 |
| Frequency | 频率 |
(temporal frequency, f) (Unit Hz) The number of cycles per second in an oscillation or the repetition rate for a cyclic process. （时间频率，f）（单位Hz）振荡中每秒的周期数或循环过程的重复率。 |
| Dynamic load rating (Unit N) | 额定动载荷（单位N） |
The allowable load on a component or structure when the loading is not static. 当负载不是静态时，组件或结构上的允许负载。 |
| 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。 |
| Rated power (Unit kW or hp) | 额定功率（单位：千瓦或马力） |
(rated capacity, rated horsepower) The maximum power output that can be sustained continuously for any power-producing machine or system, such as an engine or a power plant. （额定容量、额定马力）任何发电机器或系统（如发动机或发电厂）可连续维持的最大功率输出。 |
| British thermal unit (BTU, Btu) | 英热单位（BTU，Btu） |
An obsolete (non-SI) imperial unit of energy defined as the energy required to raise the temperature of one pound of pure water at 68°F by 1°F. The conversion to SI is 1 Btu = 1.055 056 × 103 J. 一种已被淘汰的（非SI）英制能量单位，定义为将68°F的一磅纯水的温度升高1°F所需的能量。转换为SI为1Btu=1.055056×103J。 |
| 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。 |
| 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。 |
| Corrosion | 腐蚀 |
The deterioration of an exposed metal surface due to electrochemical oxidation with its surroundings. In the oxidation reaction, metal atoms give up electrons which are transferred to form another chemical species by a reduction reaction, usually with hydrogen and/or oxygen. A common example is the formation of the iron oxide rust Fe(OH)3 on iron or steel in moist air or water. Rust breaks away easily, exposing fresh iron to the atmosphere, whereas the corrosion product of some metals forms an adherent layer that prevents further oxidation reaction at fresh metal, an effect known as passivation. Examples include aluminium oxide on aluminium, chromium oxide on chromium, chromium oxide on alloys containing chromium such as stainless steels, and the patina formed on copper and zinc. Corrosion protection takes many forms. Good design to avoid crevices and stress is important. In some situations, substances known as inhibitors may be added to the environment to decrease its corrosiveness. The electrochemical nature of corrosion results in some metals having a greater tendency for oxidation than others. Zinc has a stronger tendency than iron and this is made use of in galvanizing. This is one example of cathodic protection, in which one metal is connected electrically to a more reactive metal, called a sacrificial anode, that oxidizes by giving up electrons and so protects the first metal. Coatings may be used to resist corrosion. Paints, plating, and diffusion coatings are the most common and the electrochemical process of anodizing is used to deliberately form a passive layer of oxide on aluminium alloys. Material selection plays a major role. For example, stainless steels with their high chromium content are widely used in corrosive environments. 暴露的金属表面由于与周围环境的电化学氧化而劣化。在氧化反应中，金属原子放弃电子，这些电子通过还原反应（通常与氢和/或氧）转移形成另一种化学物质。一个常见的例子是在潮湿的空气或水中在铁或钢上形成氧化铁锈Fe(OH)3。铁锈很容易脱落，将新鲜铁暴露在大气中，而一些金属的腐蚀产物形成一层粘附层，防止新鲜金属发生进一步的氧化反应，这种效果称为钝化。实例包括铝上的氧化铝、铬上的氧化铬、含铬合金上的氧化铬如不锈钢，以及铜和锌上形成的铜绿。腐蚀防护有多种形式。避免裂缝和应力的良好设计非常重要。在某些情况下，可以向环境中添加称为抑制剂的物质，以降低其腐蚀性。腐蚀的电化学性质导致一些金属比其他金属具有更大的氧化倾向。锌比铁具有更强的倾向性，这可用于镀锌。这是阴极保护的一个例子，其中一种金属与活性更强的金属（称为牺牲阳极）电连接，牺牲阳极通过释放电子进行氧化，从而保护第一种金属。涂层可用于抗腐蚀。油漆、电镀和扩散涂层是最常见的，阳极氧化的电化学过程用于有意在铝合金上形成一层钝化氧化物。材料选择起着重要作用。例如，铬含量高的不锈钢广泛用于腐蚀性环境。 |
| 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。 |
| Rated flow (Unit m³/s or kg/s) | 额定流量（单位：m³/s或kg/s） |
In a hydraulic system or machine, the volume or mass flow rate a manufacturer specifies for a component as the maximum desirable for it to function as designed. 在液压系统或机器中，制造商为部件指定的体积或质量流量是其按设计运行所需的最大值。 |
| U-bend | U形管 |
U-bend A 180° bend in a pipe. 180°弯曲的管道。 |
| Hydrodynamics | 流体力学 |
A term sometimes used to mean fluid dynamics, even when the fluid is a gas or a liquid other than water. 有时用于表示流体动力学的术语，即使流体是气体或水以外的液体。 |
| Depth gauge | 深度计 |
1. A precision instrument, typically consisting of a machine-divided steel rule passing through a hardened-steel cross head, used to measure the depths of slots, holes, shoulders, projections, etc. 2. A device used by divers to indicate the water depth. 1. 一种精密仪器，通常由穿过硬化钢十字头的机器分割钢尺组成，用于测量槽、孔、肩部、突起等的深度。 2. 潜水员用来指示深度的装置水深。 |
| Compressibility (Unit 1/Pa) | 可压缩性（单位1/Pa） |
A measure of the reduction in volume or increase in density when a substance is subjected to an increase of pressure. It is defined as the reciprocal of the bulk modulus. Liquids and solids are normally considered incompressible, whereas gases are highly compressible. 当物质受到压力增加时体积减少或密度增加的量度。它被定义为体积模量的倒数。液体和固体通常被认为是不可压缩的，而气体是高度可压缩的。 |
| Thermodynamics laws | 热力学定律 |
The zeroth, first, second, and third laws of thermodynamics. 热力学第零、第一、第二和第三定律。 |
| Dynamic load (Unit N) | 动态负载（单位N） |
1. Loading of a component or structure by a moving object whose point of application changes with time, e.g. the live load of a train passing over a bridge. 2. A load applied to a particular part of a component or structure in a short time interval. 1. 应用点随时间变化的移动物体对部件或结构的加载，例如通过桥梁的火车的活荷载。2. 在短时间内施加到部件或结构的特定部分的载荷。 |
| Ferritic decarburization | 铁素体脱碳 |
Decarburization with sufficient loss of carbon to cause a lighter shade of tempered martensite and a significantly lower hardness than that of the adjacent base metal, with the presence of ferrite grains or grain boundary network under metallographic examination. 脱碳，碳损失充分，导致回火马氏体颜色较浅，硬度明显低于相邻母材，金相检查时存在铁素体晶粒或晶界网络。 |
| X–Y recorder | X-Y记录仪 |
A device that plots a graph of a variable y against a variable x, both in the form of voltages. 一种绘制变量y和变量x的图形的设备，两者都以伏特数的形式。 |
| Catastrophic failure | 灾难性故障 |
A sudden and total failure of a large engineering structure such as an aeroengine, aircraft, space vehicle, bridge, or dam. 大型工程结构（如航空发动机、飞机、航天器、桥梁或水坝）突然完全失效。 |
| 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。 |
| Coefficient of thermal expansion | 热膨胀系数 |
(1) Change in unit of length (or volume) accompanying a unit change of temperature, at a specified temperature. (2) The linear or volume expansion of a given material per degree rise of temperature, expressed at an arbitrary base temperature or as a more complicated equation applicable to a wide range. （1） 单位长度（或体积）随温度单位变化的变化。（2） 给定材料每上升一度的线性或体积膨胀，在任意基础温度下表示，或作为适用于宽范围的更复杂方程表示。 |
| Full hard | 全硬化 |
A temper of nonferrous alloys and some ferrous alloys corresponding approximately to a coldworked state beyond which the material can no longer be formed by bending. In specifications, a full hard temper is commonly defined in terms of minimum hardness or minimum tensile strength (or, alternatively, a range of hardness or strength) corresponding to a specific percentage of cold reduction following a full anneal. For aluminum, a full hard temper is equivalent to a reduction of 75% from dead soft ; for austenitic stainless steels, a reduction of about 50 to 55%. 有色金属合金和一些铁合金的回火状态，大致对应于冷加工状态，超过该状态，材料就不能再通过弯曲形成。在规范中，完全硬质回火通常定义为与完全退火后的特定冷压下率百分比相对应的最小硬度或最小抗拉强度（或者，硬度或强度范围）。对于铝来说，完全硬回火相当于从极软状态减少75%；对于奥氏体不锈钢，减少约50%至55%。 |
| 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。 |
| Sliding-vane compressor | 滑片压缩机 |
(rotary-vane compressor, vane compressor) A rotary compressor in which gas is compressed as the spaces between spring-loaded sliding vanes held in an offset rotor reduce as the rotor revolves within a cylindrical housing. （旋转叶片压缩机，叶片压缩机）一种旋转式压缩机，当转子在圆柱形外壳内旋转时，偏置转子中的弹簧加载滑动叶片之间的空间减小，从而压缩气体。 |
| Pitch diameter | 中径 |
For screw threads, the diameter of an imaginary cylinder, the surface of which would pass through the threads at such points that would make the width of the groove and width of the land equal to one half the pitch. 对于螺纹，指一个假想圆柱体的直径，其表面将在使凹槽宽度和焊盘宽度等于螺距一半的点穿过螺纹。 |
| Active vibration suppression | 主动振动抑制 |
The reduction of undesirable vibration in components by feedback control. 通过反馈控制减少部件中的不良振动。 |
| 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。 |
| Elastic energy | 弹性能 |
The amount of energy required to deform a material within its elastic range of behavior, neglecting small heat losses due to internal friction. The energy absorbed by a specimen per unit volume of material contained within the gage length being tested. It is determined by measuring the area under the stress-strain curve up to a specified elastic strain. See also modulus of resilience and strain energy. 材料在其弹性行为范围内变形所需的能量，忽略因内耗引起的小热损失。试样在被测标距内每单位体积材料吸收的能量。它是通过测量应力-应变曲线下达到规定弹性应变的面积来确定的。另见弹性模量和应变能。 |
| 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。 |
| Final annealing | 最终退火 |
An imprecise term used to denote the last anneal given to a nonferrous alloy prior to shipment. 一个不精确的术语，用于表示有色金属合金在装运前的最后一次退火。 |
| Die casting | 压铸 |
A process in which molten metal, particularly alloys of aluminium, magnesium, copper, and zinc, is forced under pressure (10 to 200 MPa) into a reusable hardened-steel mould machined into a die. 在压力（10至200MPa）下将熔融金属（特别是铝、镁、铜和锌的合金）强制进入加工成模具的可重复使用的硬化钢模具中的过程。 |
| Stretch-bending test | 拉伸弯曲试验 |
A simulative test for sheet metal formability in which a strip of sheet metal is clamped at its ends in lock beads and deformed in the center by a punch. Test conditions are chosen so that fracture occurs in the region of punch contact. 金属板成形性的模拟试验，其中金属板条在其端部夹紧在锁珠中，并通过冲头在中心变形。选择试验条件，以便在冲头接触区域发生断裂。 |
| 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。 |
| Hot stamping | 热冲压 |
Hot forging of brass and bronze alloys. 黄铜和青铜合金的热锻。 |
| Calorie | 卡路里 |
(cal, gram calorie, small calorie) An obsolete (i.e. non-SI) unit of energy equal to 4.186 8 J. It is the amount of energy needed to raise the temperature of 1 gram of pure airfree water from 14.5°C to 15.5°C at standard atmospheric pressure. （卡，克热量，小热量）一种已被淘汰的（即非SI）能量单位，等于4.1868J。它是在标准大气压力下将1克纯无空气水的温度从14.5℃升高到15.5℃所需的能量。 |
| 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。 |
| Interrupted aging | 分段时效 |
Aging at two or more temperatures, by steps, and cooling to room temperature after each step. 分为两个或两个以上的温度时效，按顺序并在每个步骤后冷却至室温。 |
| Stress cycles endured (N) | 承受的应力循环（N） |
The number of cycles of a specified character (that produce fluctuating stress and strain) that a specimen has endured at any time in its stress history. 试样在其应力历史中任何时间所经受的特定特征（产生波动应力和应变）的循环次数。 |
| Nanoparticles | 纳米颗粒 |
Particles with dimensions of order 1 nm which have either been introduced into microstructures for reinforcement or are present as impurities. 尺寸为1nm级的颗粒，其已被引入微结构中用于增强或作为杂质存在。 |
| Specimen | 样品 |
A test object, often of standard dimensions or configuration, that is used for destructive or nondestructive testing. One or more specimens may be cut from each unit of a sample. 用于破坏性或无损检测的测试对象，通常具有标准尺寸或配置。可以从样品的每个单位切割一个或多个样品。 |
| SI system | SI国际单位制 |
SI is an abbreviation of Système International d’Unités, i.e., the international unit measurement system – an internationally established system of measurement units built on older metric systems. SI是Système International d‘Unités的缩写，即国际单位计量系统——一种基于旧公制的国际公认计量单位系统。 |
| External load | 外部负载 |
Forces exerted on fastener and=or joint members by such external factors as weight, wind, inertia, vibration, temperature expansion, pressure, etc. Does not equal the Working load in the fastener. 由重量、风、惯性、振动、温度膨胀、压力等外部因素施加在紧固件和/或接头构件上的力。不等于紧固件中的工作负载。 |
| Stress | 应力（单位Pa） |
The intensity of the internally distributed forces or components of forces that resist a change in the volume or shape of a material that is or has been subjected to external forces. Stress is expressed in force per unit area and is calculated on the basis of the original dimensions of the cross section of the specimen. Stress can be either direct (tension or compression)or shear. 1. Stress ‘at a point’ (i.e. over a volume of material that is very small compared with that of the component or structure) is the load per unit area for every face of an infinitesimal cube surrounding the point. 2. In fluid flow the stress tensor σij is the sum of an isotropic part −pδij, δij being the Kronecker delta, having the same form as the stress tensor for a fluid at rest, p being the static pressure, and the non-isotropic, deviatoric stress tensor dij which is due entirely to the fluid motion. 内部分布力或力分量的强度，这些力或力的分量抵抗正在或已经受到外力的材料的体积或形状的变化。应力以单位面积的力表示，并根据试样横截面的原始尺寸计算。应力可以是直接（拉伸或压缩）或剪切。1.“在一点”的应力（即在与组件或结构相比非常小的材料体积上）是围绕该点的无限小立方体的每个面的单位面积载荷。2. 在流体流动中，应力张量σij是各向同性部分-pδij的总和，δij是Kroneckerδ，具有与静止流体的应力张量相同的形式，p是静压，非各向同性, 偏应力张量 dij 完全由流体运动引起。 |
| Degradation failure | 退化失效 |
Failure of a system, component, or structure owing to material degradation. 由于材料退化导致的系统、组件或结构失效。 |
| Check valve | 止回阀 |
(clack valve, non-return valve) A mechanical device that allows fluid flow in one direction only. The numerous designs include ball, diaphragm, disc, lift, split disc, and swing check valves. （瓣阀、止回阀）一种仅允许流体单向流动的机械装置。众多设计包括球阀、隔膜阀、盘阀、升降阀、分体盘阀和旋启式止回阀。 |
| 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。 |
| Blow moulding | 吹塑 |
The manufacture of hollow polymer objects (e.g. bottles) by expanding, with internal air pressure, a tube sealed at one end (parison) against the walls of a cavity mould. 通过使用内部气压使一端密封的管子（型坯）靠在型腔模具的壁上膨胀来制造中空聚合物物体（例如瓶子）。 |
| Austempered steels | 等温钢 |
Medium to high carbon steels with improved mechanical properties as a result of austempering. After heating to between 800° and 900°C to form the austenite phase, they are quenched to, and held at, just above the martensite transformation range (between 260° and 370°C) to form bainite, before cooling further. Austempering of ductile cast irons results in a microstructure of bainite and spheroidal graphite. Austempered ductile irons have excellent toughness and wear properties. 由于等温淬火，机械性能得到改善的中高碳钢。在加热到800°和900°C之间形成奥氏体相后，将它们淬火并保持在略高于马氏体转变范围（260°和370°C之间）以形成贝氏体，然后进一步冷却。球墨铸铁的等温淬火导致贝氏体和球状石墨的微观结构。等温淬火球墨铸铁具有优异的韧性和耐磨性。 |
| Torque pack | 扭矩包 |
A geared wrench which multiplies input torque and provides a read-out of output torque. In effect, a combination of a Torque wrench and a Torque multiplier. 一种齿轮扳手，可增加输入扭矩并提供输出扭矩读数。实际上，它是扭矩扳手和扭矩倍增器的组合。 |
| Flange | 法兰 |
Flange refers to a head style for bolts where there is a circular ‘flange’ under the head that acts like a washer to distribute a load. A flange is a projected flat rim or collar. 1. Annular rims at the ends of pipes (flanged pipe) or shafts by which they may be coupled together using bolts that pass through holes in the flanges (flange coupling, flange union), or by toggle clamps around the periphery. 2. An extended rim on a wheel that positions it laterally on a track. Commonly used for railway rolling stock. 3. The top and bottom parts of an I-beam. 法兰是指螺栓的头部样式，其中头部下方有一个圆形“法兰”，其作用类似于垫圈以分配载荷。凸缘是凸出的平轮辋或凸缘。1.管道（法兰管）或轴端部的环形边缘，通过这些边缘，可以使用穿过法兰孔的螺栓（法兰联轴器、法兰接头）或通过周边的肘节夹将管道连接在一起。2.车轮上的延伸轮辋，将其横向定位在轨道上。通常用于铁路车辆。3.工字梁的顶部和底部。 |
| Noble metals | 贵金属 |
Metallic elements from periods (rows) 5 and 6 of the periodic table, namely ruthenium, rhodium, palladium, silver, osmium, iridium, platinum, and gold. They resist corrosion and oxidation and are used for electrical contacts, thin-film circuits, and electroplating. Gold, silver, and platinum used for jewellery are also known as precious metals. They have face-centred cubic crystal structure and good ductility. 周期表第5和第6周期（行）中的金属元素，即钌、铑、钯、银、锇、铱、铂和金。它们抗腐蚀和氧化，用于电触点、薄膜电路和电镀。用于珠宝的金、银和铂也被称为贵金属。它们具有面心立方晶体结构和良好的延展性。 |
| Vapour | 蒸气 |
The gas-like phase of a substance at a temperature below its critical point. A vapour can be condensed to a liquid or a solid by increasing its pressure or reducing its temperature. 温度低于临界点的物质的类气相。蒸汽可以通过增加压力或降低温度冷凝成液体或固体。 |
| Teeth | 齿 |
The projecting elements on gears, cutting tools, etc. 齿轮、刀具等上的突出元件。 |
| Cap | 帽 |
A cover, often in the form of a short cylinder, one end of which is closed. Typically used to close an orifice or pipe end, on to which it can be pushed, welded, screwed, or attached with fasteners. 一种盖子，通常为短圆柱体，一端封闭。通常用于封闭孔口或管端，可将其推入、焊接、拧紧或用紧固件连接到其上。 |
| Boyle’s law | 波义耳定律 |
The product of the pressure of a gas p and its volume is constant at a given absolute temperature T. Together with Charles law, it yields the ideal gas equation p = Mrt where m is the mass of gas and R is the specific gas constant. The volume of a gas at constant temperature is inversely proportional to the pressure. This means that as pressure increases, the volume of a gas decreases. 在给定的绝对温度T下，气体的压力p与其体积的乘积是恒定的。与查尔斯定律一起，它产生了理想的气体方程p=Mrt，其中m是气体的质量，R是特定的气体常数。恒温下气体的体积与压力成反比。这意味着随着压力的增加，气体的体积会减少。 |
| Austenite finish temperature (Af) | 奥氏体完成温度（Af） |
Temperature at which the transformation of martensite into austenite completes upon heating. The same designation is also applied to nonferrous alloys in which martensite transforms into some parent phase. 加热时马氏体转变为奥氏体的温度。相同的名称也适用于马氏体转变为某些母相的有色合金。 |
| Compression fitting | 压缩接头 |
A screwed joint for pipework made resistant to leakage by permanent deformation of a closely-fitting ring, called a ferrule or olive, on tightening. 一种用于管道的螺纹接头，通过紧密配合的环（称为套圈或橄榄形）在拧紧时的永久变形来防止泄漏。 |
| Fracture | 断裂 |
(rupture) The separation of materials, components, or structures into two or more parts by the propagation of one or more cracks. Cracking may be globally elastic (brittle) or accompanied by varying degrees of plasticity (ductile). （断裂）通过一个或多个裂纹的扩展将材料、部件或结构分离成两个或更多部分。裂纹可能是整体弹性（脆性）或伴有不同程度的塑性（延性）。 |
| Yield point (Unit Pa) | 屈服点（单位Pa） |
The first stress in a material, usually less than the maximum attainable stress, at which an increase in strain occurs without an increase in stress. Only certain metals—those which exhibit a localized, heterogeneous type of transition from elastic to plastic deformation—produce a yield point. If there is a decrease in stress after yielding, a distinction may be made between upper and lower yield points. The load at which a sudden drop in the flow curve occurs is called the upper yield point. The constant load shown on the flow curve is the lower yield point. (yield strength, yield stress, Rel, Rel) The stress at which the onset of permanent (plastic) deformation (yielding) occurs in a body under increasing loading. In some materials, a yield-point phenomenon occurs in which stress falls on initial yielding and plastic deformation continues without increase in stress as strain increases further. The yield criterion is the combination of normal and shear stresses which produces yielding under multiaxial loading. 材料中的第一应力，通常小于可达到的最大应力，在该应力下应变增加而应力不增加。只有某些金属——表现出从弹性变形到塑性变形的局部、非均匀类型的金属——才会产生屈服点。如果屈服后应力降低，可区分上屈服点和下屈服点。流量曲线突然下降时的荷载称为上屈服点。流量曲线上显示的恒定载荷为较低屈服点。（屈服强度，屈服应力，Rel）在不断增加的载荷下，物体发生永久（塑性）变形（屈服）时的应力。在某些材料中，会出现屈服点现象，即应力在初始屈服时下降，随着应变进一步增加，塑性变形继续，而应力没有增加。屈服准则是在多轴载荷下产生屈服的正应力和剪应力的组合。 |
| Bolt | 螺栓 |
(machine bolt) A fastener in the form of an externally-threaded cylinder with a head on one end that is inserted through holes in assembled parts that are then held together by a nut tightened on to the thread. A bolt has an unthreaded region below the head so that when located in a hole, transverse loads are borne by two plain cylindrical surfaces in contact. In contrast, use of a machine screw, that has threads all along its length, results in threads bearing against the plain surface of a hole. Officially, a threaded fastener designed to be used with a nut. （机械螺栓）外螺纹圆柱状紧固件：一端有头的紧固件，通过装配零件上的孔插入，然后通过拧紧到螺纹上的螺母固定在一起。螺栓头部下方有一个无螺纹区域，因此当位于孔中时，横向载荷由两个接触的平面圆柱面承担。相反，使用沿其长度具有螺纹的机器螺钉，会导致螺纹支撑在孔的平面上。正式情况下，螺纹紧固件设计用于与螺母一起使用。 |
| Elastic recovery | 弹性恢复 |
Amount the dimension of a stressed elastic material returns to its original (unstressed) dimension on release of an applied load. In hardness testing, the shortening of the original dimensions of the indentation upon release of the applied load. 在释放施加的载荷时，受应力弹性材料的尺寸恢复到其原始（无应力）尺寸的量。在硬度测试中，当释放所施加的载荷时，压痕的原始尺寸缩短。 |
| Sizing | 颗粒化 |
1. A finishing operation to ensure the specified dimensions and tolerances for a component are met. 2. (size classification) Separating an aggregate of mixed particles into groups according to size using a series of screens. 1.精加工操作，以确保满足部件的规定尺寸和公差。2.（粒度分类）使用一系列筛网根据粒度将混合颗粒的聚集体分成组。 |
| Waviness | 波纹度 |
Waviness is periodic deviations from geometric surface, often sinusoidal in form and often determined by low-level oscillations of the machine-tool-workpiece system during machining. Typically, wavelengths range from 1 to 10 mm (0.04 to 0.4 in.) and wave heights from a few to several hundred micrometers. 波纹度是与几何表面的周期性偏差，其形式通常是正弦的，通常由机床-工件系统在加工过程中的低水平振荡决定。通常，波长范围为1至10毫米（0.04至0.4英寸），波高范围为几微米至几百微米。 |
| 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。 |
| Anneal to temper | 退火回火 |
A final partial anneal that softens a cold worked nonferrous alloy to a specified level of hardness or tensile strength. 将冷加工的有色金属合金软化到规定的硬度或抗拉强度水平的最终局部退火。 |
| Roots blower | 罗茨鼓风机 |
(rotary-piston blower) A positive-displacement gas compressor with two meshing lobed rotors that rotate within a close-fitting casing. Commonly used as a supercharger. （旋转活塞鼓风机）一种容积式气体压缩机，具有两个啮合的凸角转子，在紧密配合的外壳内旋转。通常用作增压器。 |
| Temper | 回火 |
(1) In heat treatment, reheating hardened steel or hardened cast iron to some temperature below the eutectoid temperature for the purpose of decreasing hardness and increasing toughness. The process also is sometimes applied to normalized steel. (2) In tool steels, temper is sometimes used, but inadvisedly, to denote the carbon content. (3) In nonferrous alloys and in some ferrous alloys (steels that cannot be hardened by heat treatment), the hardness and strength produced by mechanical or thermal treatment, or both, and characterized by a certain structure, mechanical properties, or reduction in area during cold working. （1）在热处理中，将硬化钢或硬化铸铁重新加热到共析温度以下的温度，以降低硬度和增加韧性。该工艺有时也适用于正火钢。（2）在工具钢中，有时使用回火来表示碳含量，但这是不恰当的。（3）在非铁合金和一些铁合金（不能通过热处理硬化的钢）中，通过机械或热处理或两者产生的硬度和强度，其特征是在冷加工过程中具有一定的结构、机械性能或面积减小。 |
| 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。 |
| Elastic resilience | 弹性回弹 |
The amount of energy absorbed in stressing a material up to the elastic limit; or, the amount of energy that can be recovered when stress is released from the elastic limit. 向材料施加应力直至弹性极限所吸收的能量；或者当应力从弹性极限释放时可以恢复的能量值。 |
| 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。 |
| Galling | 磨损 |
An extreme form of adhesive wear, in which large chunks of one part stick to the mating part (during sliding contact). 一种极端形式的粘着磨损，其中一个零件的大块粘在配合零件上（在滑动接触期间）。 |
| 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。 |
| Horsepower | 马力 |
Unit indicating the rate at which work is done. The electrical equivalent of one horsepower is 746 watts. 单位表示完成工作的速率。一马力的电当量为746瓦。 |
| Ballonet | 气囊 |
An airbag used in a hybrid airship. Helium gas expels air from the ballonet during ascent. Fans draw air in during descent. 混合动力飞艇中使用的安全气囊。氦气在上升过程中将空气从气囊中排出。风扇在下降过程中吸入空气。 |
| Furnace | 炉 |
1. A type of combustion chamber in which solid, liquid, or gaseous fuels are burned to supply hot gases to a boiler or other process plant. Examples include the firebox, boiler furnace (steam-generating furnace), hot-air furnace, oil-fired furnace, updraught furnace, and water-cooled furnace. 2. A chamber, sometimes having a controlled atmosphere or under vacuum (vacuum furnace), for heating and melting materials. Examples include the blast furnace, direct- and indirect-arc furnaces, the induction furnace (high-frequency furnace), muffle furnace, reverberatory furnace, and solar furnace. 1.一种燃烧室，其中燃烧固体、液体或气体燃料以向锅炉或其他工艺设备供应热气。示例包括燃烧室、锅炉炉（蒸汽发生炉）、热风炉、燃油炉、上升气流炉和水冷炉。2.用于加热和熔化材料的腔室，有时具有受控气氛或真空（真空炉）。例如高炉、直接和间接电弧炉、感应炉（高频炉）、马弗炉、反射炉和太阳能炉。 |
| Semi-rotary pump | 半回转泵 |
A form of self-priming pump, often hand-operated, suitable for pumping water and light oils such as diesel oil and petrol. As shown in the diagram, liquid is sucked into one side of the pump through flap valves and simultaneously ejected from the other side on one stroke. The sequence is reversed on each successive stroke. 一种自吸泵，通常是手动的，适用于泵送水和轻油，如柴油和汽油。液体通过翻板阀吸入泵的一侧，同时在一个冲程中从另一侧排出。在每个连续冲程上，顺序颠倒。 |
| Velocity defect (Unit m/s) | 速度亏损（单位：m/s） |
In a viscous flow, such as a boundary layer or wake, the reduction in velocity, due to friction, compared with that of the free stream. 在粘性流中，如边界层或尾迹，由于摩擦，与自由流相比，速度降低。 |
| Two-dimensional flow | 二维流 |
A fluid flow in which the velocity at any time depends upon two spatial coordinates, such as the radial and axial locations in developing pipe flow. 一种流体流动，其中任何时候的速度取决于两个空间坐标，如发展中的管道流中的径向和轴向位置。 |
| Pressure gauge | 压力表 |
An instrument used to measure absolute or gauge pressure. The sensing element may be a tube which deflects when pressurized, as in a Bourdon gauge, a bellows as in an aneroid barometer, a piezoelectric crystal, a piezoresistive element, etc. 测量绝对压力或表压的仪器。传感元件可以是加压时会偏转的管，如波登压力表、无液气压计中的波纹管、压电晶体、压阻元件等。 |
| Screw | 螺钉 |
Threaded fastener designed to be used in a tapped or untapped (e.g., wood screw) hole, but not with a nut. A fastener with a screw thread cut or rolled into its cylindrical or conical shank, intended either to cut its own thread (as in a wood screw) or engage in a threaded hole. A self-tapping screw (sheet-metal screw, tapping screw) has a sufficiently hard thread that it cuts an internal thread in thin sheet or a component made of soft material when driven into a hole in the sheet or component. The screw head is the part of a screw used to apply torque to the screw. Common screw-head designs are circular in cross section with a diametral slot or cross, or hexagonal and recessed with a cross or hexagon. A screw thread is one or more continuous helical grooves of uniform section along either the exterior surface (male thread) or the interior surface (female thread) of a cylindrical or conical body. The three-dimensional shape that results when the thread cross section is rotated and axially advanced along an axis is called a helicoid, the angle that the thread makes when projected on to the axis being called the angle of inclination. Threads are employed in fasteners such as bolts, nuts, and screws; location and measuring instruments; in power drives; in some electrical fittings (Edison thread); and on the ends of crankshafts to suppress oil leakage (thrower thread). Parallel threads are formed on cylinders; tapered threads on cones, typically with a taper rate of 1:16. A screw with a righthanded thread appears to move away from the observer when turned clockwise. All standard screws, bolts and nuts have right-hand threads, but left-handed threads are sometimes employed. The axial distance between corresponding points on adjacent threads is called the screw pitch or screw rate and, for a single continuous helical groove (a single-start thread), is the same as the change in axial distance (the lead) between a nut and the head of a bolt during one revolution, the number of thread forms per mm then being the reciprocal of the pitch. For the same screw diameter, coarse threads have fewer threads per mm than fine threads. A multiple-start screw thread (usually coarse, see later) consists of two or more identical threads running simultaneously along its axis so as to provide greater bearing area and greater velocity ratio. The starts are separated by 180° (double start), 120° (triple start), 90° (quadruple start) etc., depending upon the number of threads. Thus, in double-start threads, the lead is twice the pitch; and so on. The axial distance between corresponding points on two adjacent threads in a multiple start thread is called the divided pitch. The position on a screw thread where there is equal distance between the flanks on the solid part of the thread and in the space between the threads is the pitch point, the associated diameter of which is termed the pitch diameter. The basic nomenclature for threads, some of which is common with that for toothed gearing, is shown in the diagrams. A helix formed or cut on a cylindrical surface which may advance along the axis to the right or left. The helix may be single or multiple. 一种螺纹紧固件，设计用于攻丝或未攻丝（如木螺钉）孔，但不与螺母配合使用。其螺纹被切割或卷成圆柱形或锥形柄，用于切割自身螺纹（如木螺钉）或嵌入螺纹孔。自攻螺钉（钣金螺钉、自攻螺钉）具有足够硬的螺纹，当打入薄板或部件中的孔时，它会在薄板或软材料部件中切割内螺纹。螺钉头是螺钉的一部分，用于向螺钉施加扭矩。常见的螺钉头设计为横截面为圆形，带有直径槽或十字，或为六边形，并带有十字或六边形凹槽。螺纹是沿圆柱形或锥形体的外表面（外螺纹）或内表面（内螺纹）具有均匀截面的一个或多个连续螺旋槽。当螺纹横截面旋转并沿轴轴向前进时产生的三维形状称为螺旋面，螺纹投影到轴上时形成的角度称为倾角。螺纹用于紧固件，如螺栓、螺母和螺钉；定位和测量仪器；在动力驱动中；在一些电气配件中（爱迪生螺纹）；并安装在曲轴端部，以抑制漏油（抛掷器螺纹）。在圆柱体上形成平行螺纹；圆锥上的锥形螺纹，通常具有1:16的锥形率。当顺时针旋转时，具有右手螺纹的螺钉似乎会远离观察者。所有标准螺钉、螺栓和螺母都有右手螺纹，但有时使用左手螺纹。相邻螺纹上对应点之间的轴向距离称为螺距或螺纹率，对于单个连续螺旋槽（单个起始螺纹），与螺母和螺栓头之间的轴向间距（导程）在一周内的变化相同，每mm的螺纹形式数为螺距的倒数。对于相同的螺钉直径，粗螺纹的每毫米螺纹数少于细螺纹。多头螺纹（通常为粗螺纹，见下文）由两个或多个沿其轴线同时延伸的相同螺纹组成，以提供更大的承载面积和更大的速比。根据螺纹的数量，起点之间的间隔为180°（双起点）、120°（三起点）、90°（四起点）等。因此，在双起始螺纹中，导程是螺距的两倍；多起点螺纹中两个相邻螺纹上对应点之间的轴向距离称为分割螺距。螺纹上的位置，即螺纹实体部分的侧面和螺纹之间的空间之间的距离相等，即节点，其相关直径称为节径。图中显示了螺纹的基本术语，其中一些与齿轮传动的基本术语相同。在圆柱面上形成或切割的螺旋线，可沿轴线向右或向左前进。螺旋可以是单个或多个。 |
| Population | 集合 |
The hypothetical collection of all possible test specimens that could be prepared in the specified way from the material under consideration. Also known as universe. 从所考虑的材料中以规定方式制备的所有可能试样的假设集合。也称为体系。 |
| Maraging steels | 马氏体时效钢 |
Very high-strength iron alloys named after ‘martensitic’ and ‘aging’. They contain nickel, chromium, cobalt, and molybdenum, and form martensite on air cooling with a strength of about 1 GPa. When reheated to about 500°C and aged for some hours, a room-temperature strength of some 2.4 GPa is reached. 以“马氏体”和“时效”命名的超高强度铁合金。它们含有镍、铬、钴和钼，在空气冷却下形成强度约为1GPa的马氏体。当再加热至约500°C并老化数小时时，室温强度达到约2.4GPa。 |
| 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°。 |
| Austenitizing | 奥氏体化 |
Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing). When used without qualification, the term implies complete austenitizing. 通过将铁合金加热到转变范围（部分奥氏体化）或高于转变范围（完全奥氏体化）来形成奥氏体。当不加限定地使用时，该术语意味着完全奥氏体化。 |
| Thermoelectric junction | 热电结 |
A welded, soldered, or twisted connection between the ends of two wires of dissimilar metals, as in a thermocouple. 两根不同金属线的末端之间的焊接、锡焊或绞合连接，如热电偶。 |
| Water-jet cutting | 水射流切割 |
Cutting of materials such as rock by means of a high-speed jet of water containing abrasive particles. 通过含有磨料颗粒的高速水射流切割岩石等材料。 |
| 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。 |
| Compression wave | 压缩波 |
(dilatation wave) In a fluid or a solid, a progressive wave or wavefront that compresses the medium through which it propagates. （膨胀波）在流体或固体中，压缩介质传播的行波或波前。 |
| Structural-integrity analysis | 结构完整性分析 |
Assessment of components and structures for likelihood of failure by buckling, fracture, yielding, etc. under conditions of normal and accident loading. 在正常和事故荷载条件下，评估部件和结构因屈曲、断裂、屈服等而失效的可能性。 |
| Radian (rad) | 弧度（rad） |
A coherent derived SI unit defined as the plane angle subtended at the centre of a circle by an arc having a length equal to the radius. Thus 2π radians are equivalent to 360° and 1 rad ≈ 57.3°. 一种相干导出的国际单位制单位，定义为在圆心处被长度等于半径的弧对向的平面角。因此，2π弧度相当于360°和1弧度≈57.3°. |
| 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。 |
| 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。 |
| 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。 |
| 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）。 |
| Combustion efficiency | 燃烧效率 |
(source efficiency, ηCOMB) A performance measure for combustion equipment defined by ηCOMB = amount of heat released during combustion/(calorific value of the fuel burned). （源效率，ηCOMB）燃烧设备的性能度量，定义为ηCOMB=燃烧过程中释放的热量/（燃烧燃料的热值）。 |
| Mole number (N) | 摩尔数（N） |
The number of moles in a given mass m of a substance, equal to m divided by the molar mass of the substance. 摩尔数物质给定质量m中的摩尔数，等于m除以物质的摩尔质量。 |
| Barrier protection | 屏障保护 |
The coating on a fastener is said to provide barrier protection if it merely isolates the fastener from the environment. Paint, for example, provides barrier protection. 如果仅将紧固件与环境隔离，则据说紧固件上的涂层可提供屏障保护。例如，油漆提供屏障保护。 |
| Black oxide | 黑色氧化物 |
A black finish on a metal produced by immersing it in hot oxidizing salts or salt solutions. 通过将金属浸入热氧化盐或盐溶液中产生的黑色饰面。 |
| Dead load (Unit N) | 静载（单位N） |
A load on a component or structure that is steady with time, e.g. the self-weight of a bridge. 部件或结构上随时间稳定的载荷，例如桥梁的自重。 |
| Bimetallic strip | 双金属片 |
A strip formed by welding, riveting or brazing together two metals having different coefficients of expansion, which causes the strip to curl when its temperature changes. Typical combinations are steel and copper or steel and brass. 将两种膨胀系数不同的金属焊接、铆接或钎焊在一起形成的带材，当温度变化时，带材会卷曲。典型的组合是钢和铜或钢和黄铜。 |
| Electrode | 电极 |
The two metallic bodies in a battery or Corrosion cell which give up electrons (the Anode) or which attract them (the Cathode). 电池或腐蚀电池中释放电子（阳极）或吸引电子（阴极）的两个金属体。 |
| 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。 |
| Celsius | 摄氏度 |
The temperature scale based on the freezing point of water (0ºC) and the boiling point of water (100ºC). The interval between these points is divided into 100 degrees. The scale was devised by Anders Celsius. 基于水的冰点（0ºC）和水的沸点（100ºC）的温标。这些点之间的间隔被划分为100度。这个比例是由安德斯·摄氏设计的。 |
| Quench annealing | 淬火退火 |
Annealing an austenitic ferrous alloy by solution heat treatment followed by rapid quenching. 通过固溶热处理然后快速淬火对奥氏体铁合金进行退火。 |
| Binary vapour cycle | 二元蒸气循环 |
A power cycle which combines a steam cycle at relatively low temperature (the bottoming cycle) with a higher temperature cycle (the topping cycle) in which a working fluid such as mercury, sodium or potassium is used. 一种动力循环，它将相对低温的蒸汽循环（底部循环）与高温循环（顶部循环）相结合，其中使用了诸如汞、钠或钾之类的工作流体。 |
| 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。 |
| Turbine pump (turbopump) | 涡轮泵 |
An axial or centrifugal pump driven by a turbine. Typically used to supply fuel to the combustion chamber of a rocket engine such as on the space shuttle. 由涡轮驱动的轴向或离心泵。通常用于向火箭发动机（如航天飞机）的燃烧室供应燃料。 |
| Centre line | 中心线 |
1. In an engineering drawing, a line of symmetry. 2. An imaginary line along a pipe, duct, or shaft that defines an axis of symmetry. 3. An imaginary straight line parallel to the intended direction of a surface located such that the areas above and below the line and the real wavy (rough) surface cancel out. 1.在工程图中，对称线。2.沿着管道、管道或竖井定义对称轴的假想线。3.一条平行于表面预期方向的假想直线，该直线上方和下方的区域与真实的波状（粗糙）表面相抵消。 |
| Barometer | 气压计 |
An instrument used to measure atmospheric pressure. An instrument for measuring atmospheric pressure. There are two main types – the mercury barometer, and the aneroid barometer. 用于测量大气压力的仪器。有两种主要类型——水银气压计和无液气压计。 |
| Finishing temperature | 终轧温度 |
The temperature at which hot working is completed. 完成热加工的温度。 |
| Biomedical engineering | 生物医学工程 |
The application of engineering principles and methodology to the medical field. Examples involving mechanical engineering include the design and construction of artificial limbs and hearts, heart-lung machines, prosthetic eyes, and orthopaedic implants such as hip joints and pins to stabilize fractured bones. 工程原理和方法在医学领域的应用。涉及机械工程的例子包括假肢和心脏、心肺机、假眼和骨科植入物（如髋关节和用于稳定骨折骨骼的销钉）的设计和建造。 |
| Forge | 锻造 |
To shape metal while holt and plastic by a hammering or forcing process. Dies used in process. 通过锤击或强制过程使金属成型，同时保持塑料成型。过程会使用模具。 |
| Self-loosening | 自松动 |
The process by which a supposedly tightened fastener becomes loose, as a result of vibration, thermal cycles, shock, or anything else which cause transverse slip between joint members and between male and female threads. Vibration loosening is a common, but special, case of self-loosening. 由于振动、热循环、冲击或任何其他导致接头构件之间以及阳螺纹和阴螺纹之间横向滑动的原因，紧固件松动的过程。振动松动是自松动的一种常见但特殊的情况。 |
| Speed of rotation (N) | 转速（N） |
(Unit rps or rpm) For an object rotating about a fixed axis, the speed of rotation is the number of turns (revolutions) of the object per unit time. It is equal to the angular velocity Ω (or ω) (unit rad/s) divided by 2π. （单位rps或rpm）对于绕固定轴旋转的物体，旋转速度是物体每单位时间的转数。它等于角速度Ω（或ω）（单位rad/s）除以2π。 |
| 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。 |
| Power | 力能 |
The rate of doing work or of producing or consuming energy. The unit of power is the watt, W, where 1 W = 1 N m/s. 做功或产生或消耗能量的速度。功率单位为瓦特，W，其中1W=1N m/s。 |
| Galvanic protection | 电流保护 |
The coating on a fastener is said to provide galvanic protection if it is more anodic than the fastener and will, therefore, be destroyed instead of the fastener. Zinc plate (galvanizing) provides galvanic protection to steel fasteners, for example. 如果紧固件上的涂层比紧固件更具阳极性，则据说它可以提供电流保护，将会因此被破坏而不是紧固。例如，锌板（镀锌）为钢紧固件提供电流保护。 |
| Plane-strain fracture toughness (KIc) | 平面应变断裂韧性（KIc） |
The crack extension resistance under conditions of crack-tip plane strain. 裂纹尖端平面应变条件下的裂纹扩展阻力。 |
| Closed system | 封闭系统 |
A closed thermodynamic system consists of a fixed amount of mass. No mass can cross its boundary although energy can, in the form of work or heat, and its volume can change. 一个封闭的热力学系统由一定量的质量组成。能量可以以功或热的形式存在，其体积可以改变，但没有质量可以越过它的边界。 |
| Extra hard | 额外硬化 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength and hardness about one-third of the way from full hard to extra spring temper. 有色合金和一些铁合金的回火，其特征是抗拉强度和硬度大约是从完全硬回火到额外弹簧回火的三分之一。 |
| Effective radius of nut, bolt head, or threads | 螺母、螺栓头或螺纹的有效半径 |
Distance between the geometric center of the part and the circle of points through which the resultant contact forces between mating parts passes. Must be determined by integration. 零件几何中心与配合零件之间的合力通过的点圆之间的距离。必须通过积分来确定。 |
| Hot dipping | 热浸 |
(hot-dip galvanizing) A process of coating an iron, steel, or aluminium object with a thin layer of zinc by passing it through a bath of molten zinc at a temperature of about 460°C. （热浸镀锌）通过使铁、钢或铝物体通过温度约为460°C的熔融锌浴，在铁、钢或铝物体上镀上一层薄薄的锌层的工艺。 |
| Absorption dynamometer | 吸收式测功机 |
A dynamometer in which input work or power is dissipated by mechanical friction, electrical resistance, hydraulic resistance, etc. 通过机械摩擦、电阻、液压阻力等耗散输入功或功率的测功机。 |
| Pressure chamber | 压力室 |
A chamber in which components or devices can be subjected to high or low fluid (liquid or gas) pressure. 部件或装置可承受高或低流体（液体或气体）压力的腔室。 |
| 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。 |
| Malleable cast iron | 可锻铸铁 |
A cast iron made by prolonged annealing of white cast iron in which decarburization or graphitization, or both, take place to eliminate some or all of the cementite. The graphite is in the form of temper carbon. If decarburization is the predominant reaction, the product will exhibit a light fracture surface, hence, “whiteheart malleable;” otherwise, the fracture surface will be dark, hence, “blackheart malleable.” Ferritic malleable has a predominantly ferritic matrix; pearlitic malleable may contain pearlitic, spheroidite or tempered martensite depending on heat treatment and desired hardness. 白口铸铁一种通过长时间退火制成的铸铁，脱碳，石墨化，或两者都发生，以消除部分或全部渗碳体。石墨是回火碳的形式。如果脱碳是主要反应，产品将呈现出较轻的断裂表面，“白心可锻”。否则，断裂表面将变暗，“黑心可锻”。铁素体可锻性材料主要为铁素体基体；根据热处理和所需硬度，珠光体可锻材料可能包含珠光体、球状体或回火马氏体。 |
| Fracture mechanics | 断裂力学 |
The stress analysis of bodies containing cracks. The use of stressconcentration factors and other correction factors of traditional strength of materials is inadequate when flaws are present initially (or develop during loading), since fracture depends not only on stress but also the size of the crack. Traditional strength of materials stress calculations cannot predict either the safe working stress in the presence of a known flaw, or the critical size of flaw just tolerable with a given working stress. 含裂纹物体的应力分析。当初始存在缺陷（或在加载过程中形成缺陷）时，使用应力集中系数和传统材料强度的其他修正系数是不够的，因为断裂不仅取决于应力，还取决于裂纹的大小。传统的材料强度应力计算既不能预测已知缺陷存在时的安全工作应力，也不能预测给定工作应力下可容忍的缺陷临界尺寸。 |
| Microscopic stresses | 微观应力 |
Residual stresses that vary from tension to compression in a distance (presumably approximating the grain size) that is small compared with the gage length in ordinary strain measurements. They are not detectable by dissection methods, but can sometimes be measured from line shift or line broadening in an x-ray diffraction pattern. 与普通应变测量中的标距相比，从拉伸到压缩的距离（大概接近晶粒尺寸）较小的残余应力。它们无法通过解剖方法检测到，但有时可以通过x射线衍射图案中的线位移或线加宽来测量。 |
| Degradation of energy | 能源退化 |
Conversion of energy into forms of lower usefulness due to irreversibilities in energy transfer and conversion processes. The increase in entropy can be regarded as a measure of the degradation of energy. 由于能量转移和转换过程中的不可逆性，将能量转换为低效形式。熵的增加可以看作是能量退化的量度。 |
| Vane engine (vane motor) | 叶片发动机（叶片马达） |
A rotary engine in which high-pressure hydraulic fluid in the spaces between spring-loaded sliding vanes held in an offset rotor acts on the vanes, causing the rotor to revolve within a cylinder. The design is much like a sliding-vane compressor, as is that of a vane pump, used to pump liquids. 一种旋转式发动机，其中偏置转子中装有弹簧的滑动叶片之间的高压液压流体作用在叶片上，使转子在气缸内旋转。这种设计很像滑动叶片压缩机，就像用于泵送液体的叶片泵一样。 |
| Screw conveyor | 螺旋输送机 |
(auger, spiral conveyor, worm conveyor) A machine for bulk handling of semi-solid materials, consisting of a helical screw which rotates in a trough or casing. （螺旋输送机、螺旋输送机、蜗杆输送机）一种用于散装搬运半固态材料的机器，由在槽或外壳中旋转的螺旋螺杆组成。 |
| Impact testing | 冲击测试 |
Determination of the mechanical properties of materials under high-rate conditions. Often determined from the behaviour of a testpiece when struck by a pendulum or a weight falling from a known height, or when sandwiched between two Hopkinson bars. 在高速条件下测定材料的机械性能。通常根据测试件在被钟摆撞击或从已知高度坠落的重物或夹在两个霍普金森棒之间时的行为来确定。 |
| Recrystallization annealing | 再结晶退火 |
Annealing cold-worked metal to produce a new grain structure without phase change. 退火冷加工金属以产生新的晶粒结构而不发生相变。 |
| Critical compression ratio | 临界压缩比 |
1. The compression ratio for incipient knock of hydrocarbon fuels as determined in a variable-compression single-cylinder piston engine. 2. The compression ratio at which an air–fuel mixture will spontaneously ignite due to the temperature increase produced. 1.在可变压缩单缸活塞发动机中确定的烃类燃料初期爆震的压缩比。2.空气-燃料混合物由于产生的温度升高而自燃的压缩比。 |
| Hypereutectoid alloy | 过共析合金 |
In an alloy system exhibiting a eutectoid, any alloy whose composition has an excess of alloying element compared with the eutectoid composition, and whose equilibrium microstructure contains some eutectoid structure. 在呈现共晶的合金系统中，合金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。 |
| Bolt stress (Unit Pa) | 螺栓应力（单位Pa） |
The axial tensile stress induced in a bolt by tightening. 通过拧紧在螺栓中产生的轴向拉应力。 |
| Corrosion failure | 腐蚀失效 |
1. The failure of a component or structure after corrosion has reduced the load-bearing area to an unsupportable level. 2. A situation in which a mechanism cannot function owing to corrosion products preventing free movement at joints. 1、部件或结构在腐蚀后失效，使承重面积减少到无法支撑的程度。2.由于腐蚀产物阻止关节处的自由运动，导致机构无法运行的情况。 |
| Collar | 圈、箍 |
A ring secured to, or integral with, a shaft to give axial location. 固定在轴上或与轴成一体以提供轴向位置的环。 |
| Clutch | 离合器 |
A device for connecting and disconnecting rotating shafts, for example between an engine and a gearbox. 一种用于连接和断开旋转轴的装置，例如在发动机和变速箱之间。 |
| Blank nitriding | 空白渗氮 |
Simulating the nitriding operation without introducing nitrogen. This is usually accomplished by using an inert material in place of the nitriding agent or by applying a suitable protective coating to the ferrous alloy. 在不引入氮气的情况下模拟氮化操作。这通常通过使用惰性材料代替氮化剂或通过在铁合金上施加合适的保护涂层来实现。 |
| Crack length (depth) (a) | 裂纹长度（深度）（a） |
In fatigue and stress corrosion cracking, the physical crack size used to determine the crack growth rate and the stress-intensity factor. For the compact-type specimen, crack length is measured from the line connecting the bearing points of load application. For the center-cracked-tension specimen, crack length is measured from the perpendicular bisector of the central crack. 在疲劳和应力腐蚀裂纹中，用于确定裂纹扩展速率和应力强度因子的物理裂纹尺寸。对于紧凑型试样，裂纹长度从连接载荷施加点的线开始测量。对于中心裂纹拉伸试样，从中心裂纹的垂直平分线测量裂纹长度。 |
| True stress (σ) (Unit Pa) | 真应力（σ）（单位Pa） |
The value obtained by dividing the load applied to a member at a given instant by the cross-sectional area over which it acts. Compare with engineering stress. The applied load on a test specimen divided by the current cross-section area over which it acts. σ = s expε where s is the engineering stress given by the applied load divided by the original cross-section area over which it acts, and ε is the true strain. 通过将给定时刻施加在构件上的荷载除以其作用的横截面积而获得的值。与工程应力相比。施加在试样上的荷载除以其作用的当前横截面积。σ=s expε，其中s是由施加荷载除以其作用的原始横截面面积得出的工程应力，ε是真实应变。 |
| 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。 |
| Rotary valve (rotating valve) | 旋转阀 |
A cylindrical or conical plug in which there is a transverse hole through which fluid can flow when the hole is aligned with the adjacent piping. 一种圆柱形或锥形塞，其中有一个横向孔，当该孔与相邻管道对齐时，流体可通过该孔流动。 |
| Age softening | 时效软化 |
Spontaneous decrease of strength and hardness that takes place at room temperature in certain strain hardened alloys, especially those of aluminum. 某些应变硬化合金，尤其是铝合金，在室温下会发生强度和硬度的自发降低。 |
| Base metal hardness | 母材硬度 |
Hardness closest to the surface (when traversing from core to outside diameter) just before an increase or decrease occurs, denoting, respectively, carburization or decarburization. 在发生增加或减少之前最接近表面的硬度（从芯部到外径时），分别表示渗碳或脱碳。 |
| 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。 |
| Pulse | 脉冲 |
An increase or decrease in the magnitude of a physical quantity, such as pressure, voltage, or force, with a time scale short compared with other time scales in a process, after which there is a return to the original level. 物理量的大小的增加或减少，如压力、电压或力，与过程中的其他时间尺度相比，时间尺度较短，之后返回到原始水平。 |
| Shear lip | 剪切唇 |
A narrow, slanting ridge along the edge of a fracture surface. The term sometimes also denotes a narrow, often crescent-shaped, fibrous region at the edge of a fracture that is otherwise of the cleavage type, even though this fibrous region is in the same plane as the rest of the fracture surface. 沿断裂面边缘的狭窄倾斜脊。该术语有时还表示断裂边缘处的狭窄、通常为新月形的纤维区域，否则为解理型，即使该纤维区域与断裂表面的其余部分位于同一平面内。 |
| Bulk velocity | 体积速度 |
(average velocity, V) (Unit m/s) For fluid flow in a pipe or duct, the average flow velocity, given by V = ṁ/ρA where ṁ is the mass flow rate, ρ is the fluid density, and A is the duct cross-sectional area. （平均速度，V）（单位m/s）对于管道或管道中的流体流动，平均流速，由V=ṁ/ρA给出，其中ṁ是质量流量，ρ是流体密度，A是管道截面积。 |
| Newton’s law of gravitation | 牛顿万有引力定律 |
(Newton’s law of universal gravitation) Any two bodies exert a gravitational force of attraction F on each other directed along the line joining their centres of mass, in magnitude proportional to the product of their masses and inversely proportional to the square of the distance r between them. （牛顿万有引力定律）任何两个物体沿其质心连接线相互施加引力F，其大小与其质量乘积成正比，与它们之间距离r的平方成反比。 |
| 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。 |
| 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。 |
| Length of engagement | 啮合长度 |
It is the axial measurement within which the external and internal threads have theoretical contact. 它是外螺纹和内螺纹具有理论接触的轴向测量。 |
| Cup washer | 杯形垫圈 |
A dished leather or neoprene washer fitted to the rod end in some piston-style pumps. 在某些活塞式泵中，安装在杆端的碟形皮革或氯丁橡胶垫圈。 |
| Total-loss lubrication | 全损耗润滑 |
A system in which the lubricating oil for an internal-combustion engine is burned together with the fuel. 内燃机润滑油与燃料一起燃烧的系统。 |
| Compression spring | 压缩弹簧 |
A spring that resists compression forces, usually in the form of a helix with separated coils (giving a linear axial stiffness) or a cone with separated coils (giving a non-linear axial stiffness). 一种抵抗压缩力的弹簧，通常采用带有分离线圈的螺旋形式（提供线性轴向刚度）或带有分离线圈的锥形（提供非线性轴向刚度）。 |
| Stud | 螺柱 |
A rod having thread on both ends. A headless threaded fastener, threaded on both ends, with an unthreaded body in the middle section, or threaded from end to end. Used with two nuts, or with one nut and a tapped hole. A plain cylindrical piece having a threaded portion of suitable length at each end or a continuous thread over the entire length. One end is screwed into a machine or workpiece after which a second part is placed over the stud and held in place by a nut. 两端都有螺纹的杆。无头螺纹紧固件，两端有螺纹，中间部分有无螺纹主体，或从一端到另一端有螺纹。与两个螺母或一个螺母和一个螺纹孔一起使用。一种普通的圆柱形部件，其两端具有适当长度的螺纹部分，或在整个长度上具有连续螺纹。一端拧入机器或工件，然后将第二部分放在螺柱上，并用螺母固定到位。 |
| 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。 |
| Carbon restoration | 碳修复 |
Replacing the carbon lost in the surface layer from previous processing by carburizing this layer to substantially the original carbon level. Sometimes called recarburizing. 通过将该层渗碳到基本上原始的碳水平来替换先前处理中在表面层中损失的碳。有时称为再碳化。 |
| Tension | 拉伸 |
The force or load that produces elongation. 1. The condition in a bar, belt, cable, spring, string, wire, etc. that is being pulled from either end. 2. (tensile force) (unit N) The force associated with tension as in (1). It is measured by a tension meter. 伸长力产生伸长的力或载荷。1.从两端拉出的杆、带、电缆、弹簧、线、线等的状态。2.（张力）（单位N）与张力相关的力。 |
| Hooke’s law | 胡克定律 |
Within the limit of proportionality, the extension of a material is proportional to the applied force. Approximately, it is the relationship between stress and strain in an elastic material when it is stretched. The law states that the stress (force per unit area) is proportional to the strain (a change in dimensions). The law, which holds only approximately and over a limited range, was discovered in 1676 by Robert Hooke. 在比例极限内，材料的延伸与所施加的力成比例。近似地说，它是弹性材料拉伸时应力和应变之间的关系。该定律指出，应力（单位面积的力）与应变（尺寸变化）成比例。该定律仅适用于有限的范围，由罗伯特·胡克于1676年发现。 |
| Centrifugal pump | 离心泵 |
A pump into which liquid enters axially through the eye of the casing and is then accelerated through an impeller, thereby increasing both its kinetic energy and pressure before being delivered to a ring diffuser (the volute) that further increases the liquid pressure and from which it leaves. 一种泵，液体通过泵壳的眼轴向进入，然后通过叶轮加速，从而在输送到环形扩散器（蜗壳）之前增加其动能和压力，从而进一步增加液体压力并从中流出树叶。 |
| Testing machine | 试验机 |
A machine used to apply either a steady or oscillatory or impact load to a testpiece. The load may be tensile, compressive, shear, bending, or torsional. 用于向试件施加稳定或振荡或冲击载荷的机器。载荷可以是拉伸的、压缩的、剪切的、弯曲的或扭转的。 |
| Fin | 翼 |
A thin projecting rib. 一根细长的凸肋。 |
| Brittle | 脆性材料 |
A brittle material is one that breaks, often suddenly, with no permanent deformation. Examples of brittle materials are some cast irons, glass, concrete, and some plastics. A bolt is said to be brittle if it will break when stretched only a small amount past its yield point. 脆性材料通常会突然断裂，不会产生永久变形。脆性材料的例子有一些铸铁、玻璃、混凝土和一些塑料。如果螺栓在拉伸时仅超过其屈服点一小部分就会断裂，则称其为脆性螺栓。 |
| Slug wrench | 缓动扳手 |
A box wrench with an anvil on the end of the handle. Torque is produced by striking the anvil with a sledge hammer. 柄端有铁砧的套筒扳手。扭矩是通过用大锤敲击铁砧产生的。 |
| Remaining stress | 残留应力 |
The stress remaining at a given time during a stress-relaxation test. See also stress relaxation. 在应力松弛试验期间在给定时间内剩余的应力。参见压力松弛。 |
| Cooling coil | 冷却盘管 |
A simple heat exchanger consisting of a coiled tube, typically of copper or stainless steel, through which is circulated a coolant such as a refrigerant, chilled water, or water mixed with ethylene glycol. Applications include air conditioning, process cooling, and refrigeration. 一种简单的热交换器，由通常由铜或不锈钢制成的盘管组成，冷却剂如制冷剂、冷冻水或与乙二醇混合的水通过盘管循环。应用包括空调、工艺冷却和制冷。 |
| Crack-extension resistance (KR) | 抗裂扩展性（KR） |
A measure of the resistance of a material to crack extension, expressed in terms of the stress-intensity factor, the crack-extension force, or values of Jderived using the J-integral concept. 材料对裂纹扩展的抵抗力的量度，以应力强度因子、裂纹扩展力或使用J积分概念导出的J值表示。 |
| Fracture toughness | 断裂韧性 |
A generic term for measures of resistance to extension of a crack. The term is sometimes restricted to results of fracture mechanics tests, which are directly applicable in fracture control. However, the term commonly includes results from simple tests of notched or precracked specimens not based on fracture mechanics analysis. Results from tests of the latter type are often useful for fracture control, based on either service experience or empirical correlations with fracture mechanics tests. 裂纹扩展阻力测量的通用术语。该术语有时仅限于断裂力学试验的结果，这些结果直接适用于断裂控制。该术语通常包括非基于断裂力学分析的切口或预裂纹试样的简单试验结果。基于使用经验或与断裂力学试验的经验相关性，后一类试验的结果通常有助于断裂控制。 |
| Gauge | 测量 |
1. Any instrument for measuring or checking dimensions, including adjustable gauges such as a micrometer and non-adjustable gauges such as go/no-go limit gauges that indicate the maximum and minimum dimensions allowable in a component during manufacture. 2. A term often used to mean an instrument, e.g. pressure gauge. 3. The diameter of a wire or thickness of a sheet according to a standard. 4. The distance between the rails of a railway track. 1. 任何用于测量或检查尺寸的仪器，包括可调节量规（例如千分尺）和不可调节量规（例如指示制造过程中组件允许的最大和最小尺寸的通过/不通过限制量规）。2. 常用于表示仪器的术语，例如压力表。3.根据标准的线材直径或片材厚度。4.铁路轨道的钢轨之间的距离。 |
| 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。 |
| Coefficient of restitution (e) | 回弹系数（e） |
The ratio of the relative velocity of two colliding bodies after collision to that before. In perfectly elastic collisions e = 1; when all the impact energy is dissipated, e = 0. 两个碰撞体在碰撞后与碰撞前的相对速度之比。在完全弹性碰撞中e=1；当所有的冲击能量都消散时，e=0。 |
| Caterpillar | 毛虫式履带 |
(crawler vehicle) A vehicle that ‘lays its own road’ by running on endless belts, driven by toothed wheels, on each side. Used on soft ground where spreading of the load reduces contact stress. （履带式车辆）通过在每一侧由齿轮驱动的环形皮带运行来“铺设自己的道路”的车辆。用于负载分散可减少接触应力的松软地面。 |
| Oxidized surface (on steel) | 氧化表面（在钢上） |
Surface having a thin, tightly adhering, oxidized skin (from straw to blue in color), extending in from the edge of a coil or sheet. Sometimes called annealing border. 表面具有薄的、紧密粘附的氧化皮（从稻草色到蓝色），从线圈或薄片的边缘延伸。有时称为退火边界。 |
| Sample percentage | 样本百分比 |
The percentage of observed values between two stated values of the variable under consideration. It is a point estimate of the percentage of the population between the same two stated values. 所考虑变量的两个规定值之间的观测值百分比。它是对相同两个规定值之间的总体百分比的点估计。 |
| Half hard | 半硬化回火 |
A temper of nonferrous alloys and some ferrous alloys characterized by tensile strength about mid-way between that of dead soft and full hard tempers. 非铁合金和某些铁合金的一种回火，其特点是抗拉强度介于完全软回火和完全硬回火之间。 |
| Caustic quenching | 苛性淬火 |
Quenching with aqueous solutions of 5 to 10% sodium hydroxide (NaOH). 用5%至10%氢氧化钠（NaOH）水溶液淬灭。 |
| Elastic strain energy | 弹性应变能 |
The energy expended by the action of external forces in deforming a body elastically. Essentially, all the work performed during elastic deformation is stored as elastic energy, and this energy is recovered upon release of the applied force. 在外力作用下使物体弹性变形所消耗的能量。本质上，弹性变形过程中所做的所有功都以弹性能的形式存储，并且在释放所施加的力时恢复该能量。 |
| Circular pitch | 齿距 |
The distance from the center of one gear tooth to the center of the next gear tooth measured on the pitch line. 在节线上测量的从一个轮齿中心到下一个轮齿中心的距离。 |
| Coarse threads | 粗螺纹 |
Threads with relatively large separation between corresponding points on the threads. 螺纹上相应点之间的间距相对较大的螺纹。 |
| Temperature factor | 温度系数 |
A calibration constant used in ultrasonic measurement of bolt stress or strain. Accounts for the effects of thermal expansion and the temperature-induced change in the velocity of sound. 用于螺栓应力或应变超声波测量的校准常数。说明了热膨胀和温度引起的声速变化的影响。 |
| Compression crease | 压缩折痕 |
A crease formed during the compression of composites having a high volume fraction of filaments. These composites fail in compression by forming a crease at an angle to the loading axis. 在压缩具有高体积分数长丝的复合材料期间形成的折痕。这些复合材料通过形成与加载轴成一定角度的折痕而在压缩中失效。 |
| Radial marks | 径向标记 |
Lines on a fracture surface that radiate from the fracture origin and are visible to the unaided eye or at low magnification. Radial lines result from the intersection and connection of brittle fractures propagating at different levels. Also known as shear ledges. 断裂表面上的线，从断裂起点辐射，肉眼可见或在低放大率下可见。径向线是在不同层面上传播的脆性断裂相交和连接的结果。也称为剪切壁架。 |
| Angle of torsion | 扭转角 |
(angle of twist) (Unit ° or rad) The angle relative to a chosen section, normal to the axis of twist, through which another part of a component rotates when subjected to a torque. （扭转角）（单位°或弧度）相对于选定截面的角度，垂直于扭转轴，部件的另一部分在受到扭矩时通过该角度旋转。 |
| 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。 |
| Torsion test | 扭力测试 |
A test designed to provide data for the calculation of the shear modulus, modulus of rupture in torsion, and yield strength in shear. 为计算剪切模量、扭转断裂模量和剪切屈服强度而设计的试验。 |
| Structural engineering | 结构工程 |
A branch of civil engineering concerned with the design of buildings, dams, bridges, and other large structures. 土木工程的一个分支，涉及建筑物、水坝、桥梁和其他大型结构的设计。 |
| Shell hardening | 壳型硬化 |
A surface-hardening process in which a suitable steel workpiece, when heated through and quench hardened, develops a martensitic layer or shell that closely follows the contour of the piece and surrounds a core of essentially pearlitic transformation product. This result is accomplished by a proper balance among section size, steel hardenability, and severity of quench. 一种表面硬化工艺，在该工艺中，合适的钢工件在加热和淬火硬化后，会形成一层马氏体层或壳，该层或壳紧随工件的轮廓，并包围一个基本上为珠光体相变产物的核心。这一结果通过截面尺寸、钢淬透性和淬火强度之间的适当平衡来实现。 |
| Shear fracture | 剪切断裂 |
A ductile fracture in which a crystal (or a polycrystalline mass)has separated by sliding or tearing under the action of shear stresses. Contrast with cleavage fracture. 在剪切应力作用下，晶体（或多晶块）通过滑动或撕裂而分离的韧性断裂。与解理断裂形成对比。 |
| 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。 |
| Kilo (k) | 千（k） |
An SI unit prefix indicating a multiplier of 103; thus kilometre (km) is a unit of length equal to one thousand metres. 表示乘法器103的SI单位前缀；1千米是长度单位，等于1000米。 |
| Angle of attack (α) | 攻角（α） |
(Unit °) The angle between a reference line on a lifting body and the vector direction of the relative velocity between the body and the fluid through which it is moving. In the case of an aerofoil, turbine, or compressor blade, the usual reference line is the chord line. （单位°）升力体上的参考线与升力体与其运动通过的流体之间的相对速度的矢量方向之间的角度。在机翼、涡轮或压缩机叶片的情况下，通常的参考线是弦线。 |
| Tensile strength (Unit Pa) | 抗拉强度（单位Pa） |
In tension testing, the ratio of maximum load to original cross-sectional area. Also known as ultimate strength. The resistance that a material offers to tensile stress. It is defined as the smallest tensile stress required to break the body. (ultimate strength, ultimate tensile strength, UTS, Rm, Rm) The nominal or engineering stress given by the maximum load in a tension test divided by the original cross-sectional area of the specimen. The maximum load could be the fracture load for a brittle material, but for a ductile material it is usually taken as the load at which necking begins, beyond which the load falls. 在拉伸试验中，最大载荷与原始横截面积之比。也称为极限强度。材料对拉伸应力的抵抗力。它被定义为破坏主体所需的最小拉伸应力。（极限强度、极限抗拉强度、UTS、Rm、Rm）拉伸试验中最大载荷除以试样原始横截面积得出的标称或工程应力。对于脆性材料，最大载荷可以是断裂载荷，但对于韧性材料，最大荷载通常被视为颈缩开始时的载荷，超过该载荷时，载荷下降。 |
| Ion nitriding | 离子氮化 |
A method of surface hardening in which nitrogen ions are diffused into a workpiece in a vacuum through the use of high-voltage electrical energy. Synonymous with plasma nitriding or glowdischarge nitriding. 一种表面硬化方法，其中氮离子通过使用高压电能在真空中扩散到工件中。与等离子体氮化或辉光放电氮化同义。 |
| Vertical engine | 立式发动机 |
A piston engine having the cylinders above the crankshaft. 气缸位于曲轴上方的活塞发动机。 |
| 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。 |
| Torricellean barometer | 托里塞莱气压计 |
A vertical glass tube with its upper end sealed and the lower end submerged in a pool of mercury. The space above the mercury is under vacuum. The height to which the mercury rises up the tube is a measure of the barometric pressure. 一种垂直的玻璃管，上端密封，下端浸入汞池中。水银上方的空间处于真空状态。水银在管道中上升的高度是大气压力的量度。 |
| Fastener with waisted shank | 带腰柄的紧固件 |
Finished fastener with a shank diameter of ds < d2. 柄径ds |
| 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。 |
| Shoulder bolt | 轴肩螺栓 |
A bolt for which the unthreaded cylindrical section between the thread and the head is of larger diameter than the threaded section, precisely machined to length and diameter and hardened 一种螺栓，其螺纹和头部之间的无螺纹圆柱段的直径大于螺纹段的直径，精确加工至长度和直径并硬化 |
| 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。 |
| Relaxation | 松弛 |
The loss of tension, and therefore Clamping force, in a bolt and joint as a result of Embedment, vibration loosening, gasket creep, differential thermal expansion, etc. 由于嵌入、振动松动、垫圈蠕变、热膨胀差等原因，螺栓和接头中的张力损失，因此夹紧力损失。 |
| 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。 |
| Joule | 焦耳 |
The SI unit of energy. One joule is the work done by a force of one newton acting over a distance of one metre. The symbol is J, where 1 J = 1 N m. 国际单位制能量单位。一焦耳是一牛顿的力在一米的距离上所做的功。符号为J，其中1j=1m。 |
| Quench aging | 淬火时效 |
Aging induced by rapid cooling after solution heat treatment. 固溶热处理后快速冷却引起的时效。 |
| Cellular materials | 蜂窝材料 |
There are three broad classes of materials that have a sponge-like structure containing many small closed or open (interlinked) pores or cells. Natural cellular materials include bone, cork, sponge, and wood, and have numerous well-known uses. Wide ranges of cellular plastics are produced using blowing or foaming agents, such as air, ammonium carbonate, sodium bicarbonate, etc., to create pores during the processing of thermoplastic or thermosetting polymers. Rigid foams have moderate compressive strength and can be moulded and machined. 有三大类材料具有海绵状结构，包含许多小的封闭或开放（互连）孔或细胞。天然多孔材料包括骨骼、软木、海绵和木材，有许多众所周知的用途。使用发泡剂或发泡剂（如空气、碳酸铵、碳酸氢钠等）生产各种泡沫塑料，以在热塑性或热固性聚合物加工过程中产生孔隙。硬质泡沫具有中等抗压强度，可模制和机加工。 |
| Temper color | 回火颜色 |
A thin, tightly adhering oxide skin that forms when steel is tempered at a low temperature, or for a short time, in air or a mildly oxidizing atmosphere. The color, which ranges from straw to blue depending on the thickness of the oxide skin, varies with both tempering time and temperature. 一种薄的、紧密粘附的氧化皮，当钢在低温或短时间内在空气或轻度氧化气氛中回火时形成。颜色范围从稻草色到蓝色，取决于氧化皮的厚度，随回火时间和温度而变化。 |
| 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。 |
| Proof stress | 弹性极限应力 |
(1) The stress that will cause a specified small permanent set in a material. (2) A specified stress to be applied to a member or structure to indicate its ability to withstand service loads. （1）在材料中引起规定的小永久变形的应力。（2）施加在构件或结构上的规定应力，以表明其承受工作荷载的能力。 |
| Fatigue life (N) | 疲劳寿命（N） |
The number of cycles of stress or strain of a specified character that a given specimen sustains before failure occurs. 给定试样在失效发生之前所承受的特定特征的应力或应变的循环次数。 |
| 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℃。 |
| Coherent structure | 相干结构 |
A term given to the larger eddies of turbulent shear flow, such as boundary layers, jets, and wakes, that show distinctive correlated patterns of motion. 一个术语，用于表示湍流剪切流的较大涡流，例如边界层、射流和尾流，它们显示出独特的相关运动模式。 |
| Low-E coating | 低辐射涂层 |
(low-emittance coating) A thin metallic or metal-oxide coating on a glass sheet to absorb and reflect infrared radiation. The coating is applied either by a pyrolytic chemical vapour-deposition process (hard coat), or by sputtering (soft coat). （低辐射涂层）玻璃板上的薄金属或金属氧化物涂层，用于吸收和反射红外辐射。通过热解化学气相沉积工艺（硬涂层）或溅射（软涂层）施加涂层。 |
| Mohs scale | 莫氏硬度 |
A scale of scratch hardness originally developed for minerals. 最初为矿物开发的划痕硬度标尺。 |
| 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。 |
| Boiler and Pressure Vessel Code | 锅炉和压力容器规范 |
A large and complex document, maintained and published by the American Society of Mechanical Engineers. The code 一份庞大而复杂的文件，由美国机械工程师协会出版和维护。 |
| 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。 |
| 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。 |
| Progressive aging | 渐进时效 |
Aging by increasing the temperature in steps or continuously during the aging cycle. 通过在时效周期中逐步或连续升高温度进行增加时效。 |
| Creep limit (Unit Pa) | 蠕变极限（单位Pa） |
The maximum allowable stress under the action of which creep deformation of a material does not exceed a specified limit. 材料在其作用下的蠕变变形不超过规定限度的最大许用应力。 |
| Piston pump | 活塞泵 |
A positive-displacement pump in the basic configuration of which a piston reciprocates in a cylinder. On the suction stroke, fluid is drawn into a chamber through the inlet valve, which is then open while the outlet valve is closed. On the delivery stroke the fluid is forced out of the chamber through the outlet valve, which then opens while the inlet valve is closed. Both axial and radial configurations are common. 活塞在气缸中往复运动的一种容积泵。在吸入冲程，流体通过入口阀吸入腔室，然后在出口阀关闭时打开。在输送冲程中，流体通过出口阀被迫流出腔室，然后出口阀打开，同时入口阀关闭。轴向和径向配置都很常见。 |
| 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。 |
| Mechanical alloying | 机械合金化 |
Production of alloys from powders by consolidation, e.g. hotpressing or extrusion, followed by hot and/or cold working and final annealing. Materials such as dispersion-strengthened alloys, high-temperature aluminium alloys, and amorphous alloys can be made in this way. 通过固结（例如热压或挤压）从粉末生产合金，然后进行热和/或冷加工和最终退火。用这种方法可以制造弥散强化合金、高温铝合金和非晶合金等材料。 |
| Scratch hardness test | 划痕硬度测试 |
A form of hardness test in which a sharp-pointed stylus or corner of a mineral specimen is traversed along a surface so as to determine the resistance of that surface to cutting or abrasion. 硬度测试的一种形式，用尖头笔或矿物样品的一角沿一个表面移动，以确定该表面的抗切割或耐磨性。 |
| Bucket | 吊桶 |
1. A cup-shaped vane with a central dividing ridge attached to the periphery of the runner of an impulse water turbine such as a Pelton turbine. 2. A rotor blade in a compressor or turbine. 1.一种杯形叶片，所述杯形叶片具有附接到冲击式水轮机（例如冲击式水轮机台）的转轮的外围的中央分隔脊。2.压缩机或涡轮机中的转子叶片。 |
| Drift pin | 冲头 |
A round tapered steel pin used to align rivet holes so that the rivet will pass through the holes easily. 用于对齐铆钉孔的圆形锥形钢销，以便铆钉轻松穿过孔。 |
| Metre (m) | 米（m） |
The base unit of length in the SI system. It is equal to the distance travelled by light in vacuum in 1/299 792 458 seconds. SI系统中长度的基本单位。它等于光在真空中在1/299792458秒内传播的距离。 |
| Design stress (Unit Pa) | 设计应力（单位Pa） |
The greatest allowable stress in a component or structure that will not result in failure under normal operating conditions. 在正常操作条件下不会导致失效的部件或结构中的最大许用应力。 |
| Nut | 螺母 |
A metal fastener of square, hexagon or other shape, having an internal thread which screws onto a bolt, stud or arbor. An internally-threaded fastener used with externally-threaded bolts. Usually hexagonal in shape but there is a multitude of other geometries, such as square, for special purposes and different gripping tools. 一种方形、六角形或其他形状的金属紧固件，具有内螺纹，可拧在螺栓、螺柱或心轴上。与外螺纹螺栓一起使用的内螺纹紧固件。通常为六边形，但也有许多其他几何形状，如方形，用于特殊用途和不同的夹持工具。 |
| Stress amplitude | 应力幅值 |
One-half the algebraic difference between the maximum and minimum stress in one cycle of a repetitively varying stress. 重复变化应力的一个循环中最大和最小应力之间代数差的一半。 |
| Meyer hardness (Unit Pa) | 迈耶硬度（单位Pa） |
A material hardness similar to the Brinell hardness but based upon the projected area of the impression rather than the surface area. 与布氏硬度相似的材料硬度，但基于印模的投影面积而不是表面面积。 |
| Sigma-phase embrittlement | σ相脆化 |
Embrittlement of iron-chromium alloys (most notably austenitic stainless steels) caused by precipitation at grain boundaries of the hard, brittle intermetallic sigma phase during long periods of exposure to temperatures between approximately 565 and 980 °C (1050 and 1800 °F). Sigmaphase embrittlement results in severe loss in toughness and ductility and can make the embrittled material structure susceptible to intergranular corrosion. 铁铬合金（最显著的是奥氏体不锈钢）的脆化是由于在长时间暴露于约565至980°C（1050至1800°F）的温度下，硬脆金属间化合物σ相的晶界处沉淀造成的。σ相脆化导致韧性和延展性的严重损失，可使脆化的材料结构易于发生晶间腐蚀。 |
| Fog quenching | 雾淬 |
Quenching in a fine vapor or mist. 在细蒸汽或薄雾中淬火。 |
| Breaking stress | 断裂应力 |
The stress at failure. Also known as rupture stress. 失效时的应力。也称为破裂应力。 |
| Size effect | 尺寸效应 |
Effect of the dimensions of a piece of metal on its mechanical and other properties and on manufacturing variables such as forging reduction and heat treatment. In general, the mechanical properties are lower for a larger size. 金属件的尺寸对其机械和其他性能以及对制造变量（如锻造、压下和热处理）的影响。一般来说，尺寸越大，机械性能越低。 |
| Surface hardening | 表面硬化 |
A generic term covering several processes applicable to a suitable ferrous alloy that produces, by quench hardening only, a surface layer that is harder or more wear resistant than the core. There is no significant alteration of the chemical composition of the surface layer. The processes commonly used are carbonitriding, carburizing, induction hardening, flame hardening, nitriding, and nitrocarburizing. Use of the applicable specific process name is preferred. 一个通用术语，涵盖适用于仅通过淬火硬化产生比型芯更硬或更耐磨的表面层的合适铁合金的几种工艺。表面层的化学成分没有显著改变。常用的工艺有碳氮共渗、渗碳、感应淬火、火焰淬火、氮化和氮碳共渗。最好使用适用的特定工艺名称。 |
| Vibrograph | 示振器 |
An instrument that records vibrations in a system over time. 记录系统随时间变化的振动的仪器。 |
| Maximum load (Pmax) | 最大负载（Pmax） |
(1) The load having the highest algebraic value in the load cycle. Tensile loads are considered positive and compressive loads negative. (2)Used to determine the strength of a structural member; the load that can be borne before failure is apparent. （1）负载循环中具有最高代数值的负载。拉伸荷载视为正荷载，压缩荷载视为负荷载。（2）用于确定结构构件的强度；失效前可承受的载荷是明显的。 |
| 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。 |
| DIN | DIN |
Deutsches Institut für Normung, the German Institute for Standardization. Deutsches Institut für Normung，德国标准化研究所。 |
| Maximum material condition | 最大材料条件 |
(maximum metal condition) The situation where the volume of a manufactured component corresponds to the upper limit for all toleranced external dimensions, and to the lower limit for all internal dimensions. （最大金属条件）制造部件的体积对应于所有公差外部尺寸的上限和所有内部尺寸的下限的情况。 |
| 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。 |
| Weld penetration | 焊接熔深 |
It is the depth below the surfaces, as revealed in microstructural sections of joined metals, which is melted during welding. 它是焊接过程中熔化的连接金属的微观结构截面所显示的表面以下的深度。 |
| Relative humidity (ϕ) | 相对湿度（ψ） |
The ratio or percentage of the actual mass of moisture in a given volume of air at a given temperature to the maximum possible mass of moisture at the same temperature. 给定温度下给定体积空气中的实际水分质量与相同温度下的最大可能水分质量的比率或百分比。 |
| Conditioning heat treatment | 调质热处理 |
A preliminary heat treatment used to prepare a material for desired reaction to a subsequent heat treatment. For the term to be meaningful, the exact heat treatment must be specified. 用于制备材料的初步热处理，以便对随后的热处理进行所需的反应。为了使该术语有意义，必须指定确切的热处理。 |
| Differential heating | 差动加热 |
Heating that intentionally produces a temperature gradient within an object such that, after cooling, a desired stress distribution or variation in properties is present within the object. 加热有意在物体内产生温度梯度，从而在冷却后，在物体内出现所需的应力分布或特性变化。 |
| Nonlinear behavior | 非线性行为 |
A fastener or joint system is said to exhibit nonlinear behavior when the relationship between the External load on the joint and deformation of the parts is nonlinear, or when the relationship between increasing Preload and deformation is nonlinear. 当接头上的外部载荷与零件变形之间的关系是非线性的，或者当增加的预载荷与变形之间的联系是非线性的时，可以说紧固件或接头系统表现出非线性行为。 |
| 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。 |
| Absorption hygrometer | 吸收式湿度计 |
An instrument that determines the content of water vapour in the atmosphere by it being absorbed into a hygroscopic medium. 通过吸收到吸湿介质中来确定大气中水蒸气含量的仪器。 |
| Starting taper | 起始锥度 |
The taper on the end of a reamer or tap which aids in starting the cut. 铰刀或丝锥端部的锥度，有助于开始切割。 |
| Breaking load (Unit N) | 断裂负荷（单位N） |
The load applied at some point to a component or structure which leads to fracture. The breaking stress (breaking strength) is the average stress at which a member breaks, given by the breaking load divided by the area over which it acts. 在某个点施加到导致断裂的部件或结构的载荷。断裂应力（断裂强度）是构件断裂时的平均应力，由断裂载荷除以其作用的面积给出。 |
| Flame straightening | 火焰矫直 |
Correcting distortion in metal structures by localized heating with a gas flame. 通过使用气体火焰进行局部加热来纠正金属结构的变形。 |
| Clearance | 间距 |
(Unit m or μm) 1. The distance (if any) between mating components in an assembly. 2. The distance between two moving parts, or a moving part and stationary part, in a machine (e.g. the gap between a piston and a cylinder head). 3. With threads, the major clearance is the distance between the design form at the root of an internal thread and the crest of its mating external thread; the minor clearance is the corresponding dimension between the crest of an internal thread and the root of the external thread. （单位m或μm）1.装配体中配合组件之间的距离（如果有）。2.机器中两个运动部件之间的距离，或运动部件和静止部件之间的距离（例如活塞和气缸盖之间的间隙）。3.带螺纹时，主要间隙是内螺纹根部的设计形状与其配合的外螺纹牙顶之间的距离；小间隙是内螺纹牙顶和外螺纹牙根之间的对应尺寸。 |
| Biodiesel | 生物柴油 |
A substitute for diesel fuel derived from the oily seeds of sunflowers, oilseed rape, soya beans, etc. 从向日葵、油菜、大豆等的油性种子中提取的柴油的替代品。 |
| Grub screw | 平头螺丝 |
A short headless screw with a recess at one end to receive a screw driver or key. 一种短的无头螺钉，一端有一个凹槽，用于安装螺丝刀或钥匙。 |
| Nanotechnology | 纳米技术 |
The science and engineering of materials that have been structured on length scales of 1–100 nm, resulting in modified physical properties owing to changes in the ratio of surface area to volume (atoms on surfaces having different symmetry from those in the bulk) and because many of the fundamental physical processes that underpin the properties of materials have a characteristic length scale of a few nm, so that alteration of microstructure at the nm level alters the bulk properties. 材料科学与工程，其结构长度为1-100nm，由于表面积与体积之比的变化（表面上的原子与体中的原子具有不同的对称性），并且支撑材料性质的许多基本物理过程具有几纳米的特征长度尺度，因此改变纳米级微观结构会改变体性质。 |
| Laser sintering | 激光烧结 |
A manufacturing technique by which parts are built layer by layer (each typically 20 μm thick) from plastic or metal (Direct Metal Laser Sintering, DMLS) material in powder form, each layer being sintered by a scanning laser. 一种制造技术，通过这种制造技术，零件由粉末形式的塑料或金属（直接金属激光烧结，DMLS）材料逐层（每个厚度通常为 20 微米）构建，每一层都由扫描激光烧结。 |
| Finishing washer | 光制垫圈 |
A washer designed for use with countersunk screws. Used to enhance appearance in some applications. 设计用于沉头螺钉的垫圈。在某些应用中用于增强外观。 |
| Kilocalorie | 千卡 |
(Cal, kg-cal, kilogram-calorie, large calorie) An obsolete (i.e. non-SI) unit of energy equal to 1 000 cal. （卡，千克卡，千克卡路里，大卡路里）一种已被淘汰的（即非国际单位制）能量单位，等于1000卡。 |
| Outside diameter (Unit m) | 外径（单位：m） |
(external diameter, OD) The diameter of a circular cylindrical tube or a sphere measured between opposite points on the external surface. （外径，OD）在外表面上的相对点之间测量的圆柱管或球体的直径。 |
| Micrometer | 千分尺 |
(micrometer gauge) A mechanical-contact device for the accurate measurement of the length, width, diameter, etc. of an object, the depth of a hole, the height of a step, etc. The usual arrangement is a spindle that is moved by rotation of a thimble, the distance then being read off a vernier scale. （千分尺）一种机械接触装置，用于精确测量物体的长度、宽度、直径等、孔的深度、台阶的高度等。通常的布置是通过顶针的旋转移动主轴，然后通过游标尺读取距离。 |
| 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。 |
| Composite material | 复合材料 |
(composite structure) A general term used of two or more materials or structures acting in combination (e.g. concrete, reinforced concrete, filamentreinforced polymers, laminated materials, particulate-reinforced materials, flitched beams), resulting in values of strength, stiffness, or toughness greater than the base matrix material alone. （复合结构）用于组合作用的两种或多种材料或结构的通用术语（例如混凝土、钢筋混凝土、纤维增强聚合物、层压材料、颗粒增强材料、切割梁），从而产生强度、刚度或韧性值大于单独的基体材料。 |
| Clip gauge | 夹规 |
A displacement gauge consisting of two thin strain-gauged cantilever arms attached through knife edges to a testpiece to give the load–line displacement in fracture mechanics test pieces, or used as an extensometer in tensile tests. 一种位移计，由两个通过刀刃连接到试件上的薄应变测量悬臂组成，以提供断裂力学试件中的载荷线位移，或用作拉伸试验中的引伸计。 |
| Twist | 扭转 |
The helix produced in a cylindrical component, such as a shaft, wire, tensioned cable, or rope, when one end is rotated relative to the other. Measured either as the number of turns per unit length, or by the helix angle (twist angle). 当一端相对于另一端旋转时，在圆柱形部件（如轴、钢丝、张紧电缆或绳索）中产生的螺旋。以每单位长度的圈数或螺旋角（扭曲角）测量。 |
| 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。 |
| Equation, short form | 方程式，简写形式 |
An empirical equation which relates the torque applied to the bolt to the preload created in it, and which depends mainly on an experimentally derived factor called the Nut factor. 一个经验公式，将施加在螺栓上的扭矩与螺栓中产生的预载荷联系起来，主要取决于一个称为螺母系数的实验得出的系数。 |
| Torque wrench | 扭矩扳手 |
A manual wrench which incorporates a gage or measuring apparatus of some sort to measure and display the amount of torque being delivered to the nut or bolt. All wrenches produce torque. Only a torque wrench tells how much torque. A socket wrench or ring spanner that can be set to allow a specific torque to be applied to a nut or bolt head. 一种手动扳手，包括某种量规或测量装置，用于测量和显示传递至螺母或螺栓的扭矩量。所有扳手都产生扭矩。只有扭矩扳手才能显示扭矩大小。一种套筒扳手或梅花扳手，可设置为允许对螺母或螺栓头施加特定扭矩。 |
| Rotary piston flow meter | 旋转活塞流量计 |
A rotary liquid flow meter in which a cylindrical rotor, eccentrically mounted within a cylindrical casing, the axes of the two cylinders being parallel, is caused to rotate by the liquid flow. The flow rate is determined from the number of rotations of the rotor in a given time. 一种旋转式液体流量计，其中偏心安装在圆柱形外壳内的圆柱形转子，两个圆柱体的轴线平行，由液体流引起旋转。流量由转子在给定时间内的转数确定。 |
| 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。 |
| Yield strength | 屈服强度 |
That stress level which will create a permanent deformation of 0.2% or 0.5% or some other small, preselected, amount in a body. Approximately equal to the elastic and proportional limits of the material; a little higher than the proof strength of a bolt. The stress at which a material exhibits a specified deviation from proportionality of stress and strain. An offset of 0.2% is used for many metals. 该应力水平将在物体中产生0.2%或0.5%的永久变形，或其他一些小的、预先选定的量。近似等于材料的弹性和比例极限；略高于螺栓的强度。材料表现出与应力和应变比例的特定偏差的应力。许多金属使用0.2%的偏移量。 |
| Standard deviation (σ) | 标准偏差（σ） |
A statistical term used to quantify the Scatter in a set of data points. If the standard deviation is small, most of the data points are ‘‘nearly equal.’’ A large deviation means less agreement. The most usual measure of the dispersion of observed values or results expressed as the positive square root of the variance. The square root of variance, a measure of the spread of data about the mean value. 用于量化一组数据点中分散度的统计术语。如果标准偏差很小，则大多数数据点“几乎相等”大的偏差意味着更少的一致性。观测值或结果离散度的最常用度量，表示为方差的正平方根。方差的平方根，衡量平均值的数据分布。 |
| Fluid mechanics | 流体力学 |
The study of fluids in motion (fluid dynamics) or fluid statics where there is no relative motion between fluid particles. Fluid statics concerns primarily the variation of pressure with altitude or depth; it includes aerostatics and hydrostatics. Fluid dynamics includes the topics of aerodynamics, gas dynamics, hydraulics, hydrodynamics and many aspects of acoustics, chemical engineering, flight, lubrication, meteorology, non-Newtonian fluid flow, oceanography, power-plant technology, propulsion, and turbomachinery. 研究运动中的流体（流体动力学）或流体静力学，其中流体粒子之间没有相对运动。流体静力学主要关注压力随高度或深度的变化；它包括空气静力学和流体静力学。流体动力学包括空气动力学、气体动力学、水力学、流体动力学以及声学、化学工程、飞行、润滑、气象学、非牛顿流体流动、海洋学、发电厂技术、推进和涡轮机械的许多方面。 |
| Tightness, acceptable | 密封性，可接受的 |
Wholly leak-free joints are impossible, at least if the contained fluid is a gas, so it has been proposed that the design of a gasketed joint should start with the selection of an ‘‘acceptable’’ leak rate. The designer would dimension bolts and joint members so that the actual leak rate would never exceed this. Three standard levels of tightness have been proposed as well. 至少在所含流体为气体的情况下，完全无泄漏的接头是不可能的，因此有人建议，垫圈接头的设计应从选择“可接受”的泄漏率开始。设计师将确定螺栓和接头构件的尺寸，以便实际泄漏率永远不会超过此值。还提出了三种标准的密封性等级。 |
| Thermodynamic state | 热力学状态 |
The condition of a system or working fluid according to its properties. 系统或工作流体根据其性质的状态。 |
| 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。 |
| Rockwell superficial hardness test | 洛氏表面硬度试验 |
Same as Rockwell hardness test, except that smaller minor and major loads are used. 与洛氏硬度测试相同，只是使用较小的次要载荷和主要载荷。 |
| Coefficient of cubic expansion | 立方膨胀系数 |
The fractional increase in volume per unit temperature rise. 每单位温度升高的体积增加分数。 |
| Accommodation | 适应能力 |
The ability of a robot to respond to changes in the environment. 机器人对环境变化做出反应的能力。 |
| Preload relaxation | 预载松弛 |
Local yielding, due to excess bearing stress under nuts and bolt heads (caused by high local spots, rough surface finish, and lack of perfect squareness of bolt and nut bearing surfaces), may result in preload relaxation after preloads are first applied to a bolt. 由于螺母和螺栓头下的轴承应力过大（由局部斑点高、表面粗糙以及螺栓和螺母轴承表面缺乏完美的方正度造成），局部屈服可能会在首次向螺栓施加预载荷后导致预载荷松弛。 |
| Thermal efficiency | 热效率 |
The ratio, for a heat engine or thermodynamic cycle, of the net work output to the net heat input into the system. 对于热机或热力循环，净功输出与系统净热输入的比率。 |
| Crest | 波峰 |
The highest point of a wave or of a screw thread. 波浪或螺纹的最高点。 |
| 显示更多数据，请使用查询功能！ | ||