| 詞或詞組 | 中文 | 英文解釋中文解釋 |
|---|---|---|
| R-curve/Resistance curve | 阻力曲線 |
In linear-elastic fracture mechanics, a plot of crack-extension resistance as a function of stable crack extension, which is either the difference between the physical crack size, or the effective crack size, and the original crack size. R-curves normally depend on specimen thickness and, for some materials, on temperature and strain rate. An increase in fracture toughness with crack propagation shown by rising plots of toughness vs growing crack length. 在線彈性斷裂力學中，作為穩(wěn)定裂紋擴展函數(shù)的裂紋擴展阻力圖，即物理裂紋尺寸或有效裂紋尺寸與原始裂紋尺寸之間的差值。R曲線通常取決于試樣厚度，對于某些材料，還取決于溫度和應變率。是隨著裂紋擴展，斷裂韌性增加，表現(xiàn)為韌性與擴展裂紋長度的上升曲線。 |
| Radial engine | 徑向發(fā)動機 |
A piston engine in which the cylinders are arranged radially around the crankshaft, a design commonly used in early aircraft engines. 氣缸沿徑向圍繞曲軸布置的活塞式發(fā)動機，這種設計通常用于早期飛機發(fā)動機。 |
| Radial flow | 徑向流 |
radial flow Fluid flow for which the principal direction of flow is either radially inward or radially outward relative to an axial direction. 徑向流動流體流動的主要方向是徑向向內(nèi)或徑向向外流動。 |
| Radial load (Unit N) | 徑向負荷（單位：N） |
1. Centrifugal loading induced in a rotating body. 2. (through-wallthickness load) The radial component of loading arising from internal or external pressurization of a closed vessel. There will also be axial and hoop loading. 1.旋轉體中產(chǎn)生的離心載荷。2.（貫穿壁厚載荷）由封閉容器的內(nèi)部或外部加壓產(chǎn)生的載荷的徑向分量。還存在軸向和環(huán)向載荷。 |
| Radial marks | 徑向標記 |
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. 斷裂表面上的線，從斷裂起點輻射，肉眼可見或在低放大率下可見。徑向線是在不同層面上傳播的脆性斷裂相交和連接的結果。也稱為剪切壁架。 |
| Radial wave equation | 徑向波動方程 |
A differential equation describing the transmission of a wave in a system with radial symmetry. 描述波在徑向?qū)ΨQ系統(tǒng)中傳輸?shù)奈⒎址匠獭?/td> |
| Radial-flow compressor | 離心式壓縮機 |
A compressor in which the working gas enters the machine axially and is compressed as it flows radially out through the impeller. 一種壓縮機，其中工作氣體軸向進入機器，并在通過葉輪徑向流出時被壓縮。 |
| 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°. 一種相干導出的國際單位制單位，定義為在圓心處被長度等于半徑的弧對向的平面角。因此，2π弧度相當于360°和1弧度≈57.3°. |
| Radiation pressure (Unit μPa) | 輻射壓力（單位：μPa） |
The pressure exerted on a surface exposed to any form of electromagnetic radiation. If the radiation is absorbed, it is equal to the power-flux density divided by the speed of light. 施加在暴露于任何形式電磁輻射的表面上的壓力。如果輻射被吸收，它等于功率通量密度除以光速。 |
| Radiator | 散熱器 |
A heat exchanger used to transfer thermal energy from one fluid to another for heating or cooling purposes. Despite the name, the principal mode of heat transfer is convection rather than radiation. In motor vehicles, water circulated through the engine block is cooled as it flows through the tubes of an air-cooled heat exchanger. In domestic radiators, hot water from a boiler is circulated through a heat exchanger with a large surface area which transfers heat to the surrounding air. 一種熱交換器，用于將熱能從一種流體傳遞到另一種流體，用于加熱或冷卻。盡管有這個名字，但熱傳遞的主要方式是對流而不是輻射。在機動車輛中，通過發(fā)動機缸體循環(huán)的水在流經(jīng)風冷熱交換器的管道時被冷卻。在家用散熱器中，來自鍋爐的熱水通過具有大表面積的熱交換器循環(huán)，該熱交換器將熱量傳遞給周圍的空氣。 |
| Radioactive heat (Unit J) | 放射性熱（單位J） |
Thermal energy released from the nucleus of an atom such as uranium235 by fission due to the absorption of a neutron. Heat is also produced by radioactive decay. 鈾235等原子核因吸收中子而裂變釋放的熱能。放射性衰變也會產(chǎn)生熱量。 |
| Radiosity (J) (Unit W/m2) | 輻射度（J）（單位W/m2） |
The total radiation leaving a given surface per unit area, including emitted, reflected, and transmitted radiation. 每單位面積離開給定表面的總輻射，包括發(fā)射、反射和透射輻射。 |
| Radius of bend | 彎曲半徑 |
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. 在彎曲過程中與彎曲內(nèi)表面接觸的銷或心軸的圓柱面半徑。對于使用墊片或墊塊的180°自由彎曲或半導向彎曲，彎曲半徑為墊片或墊板厚度的一半。 |
| Raised-face flange | 凸面法蘭 |
A flange which contacts its mating joint member only in the region in which the gasket is located. The flanges do not contact each other at the bolt circle. 僅在墊圈所在區(qū)域接觸其配合接頭構件的法蘭。法蘭在螺栓圓處不相互接觸。 |
| Range of stress (Sr) | 應力范圍（Sr） |
The algebraic difference between the maximum and minimum stress in one cycle—that is, Sr?= Smax?– Smin 一個循環(huán)中最大和最小應力之間的代數(shù)差，即Sr=Smax–Smin |
| Ratchet coupling | 棘輪聯(lián)軸器 |
A joint employing a ratchet system between two shafts, so that not only does the driven shaft run in one direction only, but also the driven shaft can, if necessary, run more quickly than the driving shaft. 在兩個軸之間采用棘輪系統(tǒng)的接頭，這樣不僅從動軸只能在一個方向上運行，而且在必要時，從動軸可以比驅(qū)動軸運行得更快。 |
| Ratchet marks | 棘輪痕 |
Lines on a fatigue fracture surface that result from the intersection and connection of fatigue fractures propagating from multiple origins. Ratchet marks are parallel to the overall direction of crack propagation and are visible to the unaided eye or at low magnification. 疲勞斷裂面上由從多個源頭傳播的疲勞斷裂的交叉和連接產(chǎn)生的線。棘輪標記與裂紋擴展的整個方向平行，肉眼或低倍鏡下均可看到。 |
| Rated flow (Unit m3/s or kg/s) | 額定流量（單位：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. 在液壓系統(tǒng)或機器中，制造商為部件指定的體積或質(zhì)量流量是其按設計運行所需的最大值。 |
| Rated load (Unit N) | 額定負荷（單位：N） |
The maximum load that a structure or component has been designed to carry. 結構或部件設計承受的最大荷載。 |
| Rated power (Unit kW or hp) | 額定功率（單位：千瓦或馬力） |
(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. （額定容量、額定馬力）任何發(fā)電機器或系統(tǒng)（如發(fā)動機或發(fā)電廠）可連續(xù)維持的最大功率輸出。 |
| Recrystallization annealing | 再結晶退火 |
Annealing cold-worked metal to produce a new grain structure without phase change. 退火冷加工金屬以產(chǎn)生新的晶粒結構而不發(fā)生相變。 |
| Recrystallization temperature | 再結晶溫度 |
The approximate minimum temperature at which complete recrystallization of a cold-worked metal occurs within a specified time. 冷加工金屬在規(guī)定時間內(nèi)發(fā)生完全再結晶的近似最低溫度。 |
| Reduction in area (RA) | 縮小面積（RA） |
The difference between the original cross-sectional area of a tensile specimen and the smallest area at or after fracture as specified for the material undergoing testing. Also known as reduction of area. 拉伸試樣的原始橫截面積與試驗材料斷裂時或斷裂后的最小面積之間的差值，也稱為減少面積。 |
| Refractory materials | 耐火材料 |
Metals or ceramics that do not melt when exposed to temperature above about 1 500°C or deteriorate rapidly in a continuous temperature above about 550°C. 當暴露于高于約1500°C的溫度時不熔化或在高于約550°C的連續(xù)溫度下快速劣化的金屬或陶瓷。 |
| Regenerative pump | 渦流泵 |
?(regenerative turbine pump, peripheral pump) A pump with a double-sided impeller having a large number of radial blades. The pressure of the pumped liquid increases progressively over several revolutions of the impeller. It is? particularly suited to producing large heads at small flow rates without cavitation. （再生渦輪泵，外圍泵）具有具有大量徑向葉片的雙面葉輪的泵。泵送液體的壓力在葉輪的幾圈內(nèi)逐漸增加。它特別適合于在小流速下產(chǎn)生大水頭且不產(chǎn)生氣穴。 |
| Relative density | 相對密度 |
(specific gravity) The ratio of the density of a substance to that of a reference substance, such as water for liquids and solids, and dry air for gases. （比重）物質(zhì)密度與參考物質(zhì)密度之比，如液體和固體為水，氣體為干燥空氣。 |
| Relative humidity (?) | 相對濕度（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. 給定溫度下給定體積空氣中的實際水分質(zhì)量與相同溫度下的最大可能水分質(zhì)量的比率或百分比。 |
| 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、振動松動、墊圈蠕變、熱膨脹差等原因，螺栓和接頭中的張力損失，因此夾緊力損失。 |
| Relaxation curve | 松弛曲線 |
A plot of either the remaining, or relaxed, stress as a function of time. 剩余壓力或松弛壓力隨時間變化的曲線圖。 |
| Relaxation rate | 松弛率 |
The absolute value of the slope of a stress-relaxation curve at a given time. 給定時間應力松弛曲線斜率的絕對值。 |
| Relaxed stress | 松弛應力 |
The initial stress minus the remaining stress at a given time during a stress-relaxation test. 在應力松弛試驗期間，初始應力減去給定時間的剩余應力。 |
| Remaining stress | 殘留應力 |
The stress remaining at a given time during a stress-relaxation test. See also stress relaxation. 在應力松弛試驗期間在給定時間內(nèi)剩余的應力。參見壓力松弛。 |
| Repeatability | 重復性 |
A term used to refer to the test-result variability associated with a limited set of specifically defined sources of variability within a single laboratory. 一個術語，用于指與單個實驗室內(nèi)一組有限的特定變異源相關的測試結果變異性。 |
| Reproducibility | 再現(xiàn)性 |
A term used to describe test-result variability associated with specifically defined components of variance obtained both from within a single laboratory and between laboratories. 一個術語，用于描述與從單個實驗室內(nèi)和實驗室之間獲得的具體定義的方差分量相關的測試結果可變性。 |
| Residual preload | 殘余預載荷 |
The tension which remains in an unloaded bolted joint after Relaxation. 松弛后未加載螺栓連接中保持的張力。 |
| Residual strength (Unit N) | 剩余強度（單位：N） |
The strength of a damaged body containing defects induced by microcracking, thermal shock, etc. 包含由微裂紋、熱沖擊等引起的缺陷的受損體的強度。 |
| Residual stress (Unit Pa) | 殘余應力（單位Pa） |
Stresses that remain within a body as the result of thermal or mechanical treatment or both. (internal stress) An internal-stress system found in components that have experienced elastic unloading from non-uniform plastic-strain fields during manufacture. 由于熱處理或機械處理或兩者兼而有之而留在物體內(nèi)的應力。（內(nèi)應力）在制造期間從非均勻塑性應變場經(jīng)歷彈性卸載的部件中發(fā)現(xiàn)的內(nèi)應力系統(tǒng)。 |
| Resistance factor | 阻力系數(shù) |
Probabilistic factor representing the uncertainties in the designer’s estimate of the strength of a shear joint. Used in Load and resistance factor design. 概率系數(shù)，表示設計人員對剪切接頭強度估計的不確定性。用于載荷和阻力系數(shù)設計。 |
| Resistance thermometer | 電阻溫度計 |
A thermometer in which the sensing element is basically a metal wire, usually of platinum, for which the variation of resistance with temperature is known accurately. A resistance pyrometer is a resistance thermometer intended for use up to about 1 000°C. 一種溫度計，其中傳感元件基本上是一根金屬線，通常是鉑，可以準確地知道電阻隨溫度的變化。電阻高溫計是一種電阻溫度計，用于高達約1000°C的溫度。 |
| Retaining clip | 固定夾 |
(R-clip, hair cotter pin) A wire clip roughly with the shape of the letter R. The straight part of the clip passes through a hole drilled into a shaft or rod such that a wheel is held in position on the shaft, or the shaft is prevented from moving axially. （R形夾，開口銷）大致與字母R形狀相同的線夾。線夾的直線部分穿過鉆在軸或桿上的孔，從而將車輪固定在軸上，或防止軸軸向移動。 |
| Reverse engineering | 逆向工程 |
The disassembly of a machine, mechanism, system or device, measurement of its component parts, and identification of the materials used so that if required, a functioning replica can be produced. 拆卸機器、機構、系統(tǒng)或裝置，測量其組成部分，并識別所用材料，以便在需要時可以生產(chǎn)出功能正常的復制品。 |
| Reverse pitch (Unit °) | 反向螺距（單位°） |
The pitch of a variable-pitch propeller that produces negative thrust. 產(chǎn)生負推力的變槳距螺旋槳的槳距。 |
| Right hand thread | 右旋螺紋 |
A screw thread which advances into the mating part when turned clockwise or to the right. 順時針或向右轉動時進入配合部件的螺紋。 |
| Rivet | 鉚釘 |
A short rod with a head on one end that is inserted through aligned holes in plates to be joined, after which a second head is made on the protruding shank by hammering or forming. The most common head shapes are flat, domed, and inverse conical. In an array, the rivet pitch is the distance between the centres of adjacent rivets. Failure may occur by different mechanisms or modes. A one piece fastener consisting of a head and a body and used for fastening two or more pieces together by passing the body through a hole in each piece and then forming a second head on the body end. It cannot be removed except by taking off the head. 一種一端有頭的短桿，插入待連接板上對齊的孔中，然后通過錘擊或成型在突出的桿身上制作第二個頭。最常見的頭部形狀是扁平、圓頂和倒錐形。在陣列中，鉚釘間距是相鄰鉚釘中心之間的距離。故障可能由不同的機制或模式發(fā)生。一種一體式緊固件，由頭部和主體組成，用于將兩個或多個部件緊固在一起，方法是將主體穿過每個部件上的孔，然后在主體端部形成第二個頭部。除非取下頭部，否則無法移除。 |
| Rockwell hardness number (HR) | 洛氏硬度值（HR） |
A number derived from the net increase in the depth of impression in a Rockwell hardness test as the load on an indenter is increased from a fixed minor load to a major load and then returned to the minor load. Rockwell hardness numbers are always quoted with a scale symbol representing the penetrator, load, and dial used. 當壓頭上的載荷從固定的小載荷增加到大載荷，然后返回到小載荷時，洛氏硬度試驗中壓痕深度的凈增加值。洛氏硬度值總是用刻度符號引用，表示所用的穿透器、載荷和刻度盤。 |
| Rockwell hardness test | 洛氏硬度測試 |
An indentation-hardness test using a calibrated machine that utilizes the depth of indentation, under constant load, as a measure of hardness. A direct-reading hardness test based on depth of indentation, in which a minor load (typically 30 to 100 N) is applied before the major load (typically 120 to 1 500 N). There are different scales using conical or spherical indenters for different ranges of hardness. An indentation hardness test based on the depth of penetration of a specified penetrator into the specimen under certain arbitrarily fixed conditions. 使用校準機器進行的壓痕硬度測試，該機器利用恒定載荷下的壓痕深度作為硬度測量值。一種基于壓痕深度的直讀硬度測試，其中在主要載荷（通常為120至1500N）之前施加較小載荷（通常是30至100N）。對于不同的硬度范圍，使用錐形或球形壓頭有不同的刻度。在某些任意固定條件下，基于指定穿透器穿透試樣深度的壓痕硬度試驗。 |
| Rockwell superficial hardness test | 洛氏表面硬度試驗 |
Same as Rockwell hardness test, except that smaller minor and major loads are used. 與洛氏硬度測試相同，只是使用較小的次要載荷和主要載荷。 |
| Rolled thread | 滾制螺紋 |
A thread formed by plastically deforming the surface of the blank rather than by cutting operations. Increases fatigue life and thread strength, but is not possible (or perhaps economical) on larger sizes. 通過塑性變形坯料表面而不是通過切割操作形成的螺紋。增加疲勞壽命和螺紋強度，但不太可能（或者說是經(jīng)濟上不太可能）用于較大的尺寸。 |
| Root diameter (Unit m) | 根部直徑（單位：m） |
The diameter of the circle passing through the roots of teeth in gear teeth or screw threads. 穿過齒輪齒或螺紋中齒根的圓的直徑。 |
| Roots blower | 羅茨鼓風機 |
(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. （旋轉活塞鼓風機）一種容積式氣體壓縮機，具有兩個嚙合的凸角轉子，在緊密配合的外殼內(nèi)旋轉。通常用作增壓器。 |
| Rosette | 玫瑰形的結 |
Strain gages arranged to indicate, at a single position, strain in three different directions. 應變計布置成在單個位置指示三個不同方向的應變。 |
| Rotary blower | 旋轉鼓風機 |
(rotary compressor) A positive-displacement gas compressor which may be of the blade type, helical-screw type, meshing-lobe type (the Roots blower), or sliding-vane type. （旋轉式壓縮機）一種容積式氣體壓縮機，可以是葉片式、螺旋式、嚙合凸角式（羅茨鼓風機）或滑動葉片式。 |
| Rotary piston flow meter | 旋轉活塞流量計 |
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. 一種旋轉式液體流量計，其中偏心安裝在圓柱形外殼內(nèi)的圓柱形轉子，兩個圓柱體的軸線平行，由液體流引起旋轉。流量由轉子在給定時間內(nèi)的轉數(shù)確定。 |
| Rotary pump | 旋轉泵 |
A positive-displacement pump that pumps a liquid by rotation of internal components, such as a gear pump, lobe pump (similar to a Roots blower), or progressivecavity pump. 通過內(nèi)部部件的旋轉來泵送液體的容積泵，如齒輪泵、凸輪泵（類似于羅茨鼓風機）或螺桿泵。 |
| Rotary valve (rotating valve) | 旋轉閥 |
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. 一種圓柱形或錐形塞，其中有一個橫向孔，當該孔與相鄰管道對齊時，流體可通過該孔流動。 |
| Rotational joint (revolute joint) | 旋轉關節(jié) |
In robotics, a single degree-of-freedom joint where the controlled variable is the joint angle. 在機器人技術中，一種單自由度關節(jié)，其中受控變量為關節(jié)角度。 |
| Rotor | 轉子 |
A part of a machine that rotates on a shaft (rotor shaft) about its own axis, such as the blade-carrying discs of a turbine, the blades of a helicopter, or the rotating parts of a Roots blower. 繞軸（轉子軸）繞其自身軸線旋轉的機器部件，如渦輪葉片、直升機葉片或羅茨鼓風機的旋轉部件。 |
| Roughness | 粗糙度 |
The deviations from the wavy surface itself, caused by geometry of the cutting tool and its wear, machining conditions, microstructure of the workpiece, vibrations in the system, and so on. Surface roughness changes as a surface goes through the wearing-in process, but may then stabilize. 由刀具的幾何形狀及其磨損、加工條件、工件的微觀結構、系統(tǒng)中的振動等引起的與波狀表面本身的偏差。表面粗糙度隨著表面經(jīng)過磨合過程而變化，但隨后可能會穩(wěn)定下來。 |
| Rpm (N) | 轉速（N） |
An abbreviation for revolutions per minute. It is a widely used non-SI unit for rotational speed. The corresponding angular velocity ω in rad/s is given by πN/30. Rps (revolutions per second) is also used, the angular velocity then being 2πN. 每分鐘轉數(shù)的縮寫。它是一種廣泛使用的轉速非SI單位。相應的角速度ω，單位為rad/s，由πN/30給出。還使用Rps（每秒轉數(shù)），此時角速度為2πN。 |
| Rubber hardness | 橡膠硬度 |
The indentation hardness of rubber-like materials in which the depth of indentation under load is measured. This is a measure of elastic moduli rather than yield stress as with ductile materials, since there is little, if any, permanent impression remaining on unloading rubbery materials. 測量負載下壓痕深度的橡膠類材料的壓痕硬度。這是對彈性模量的測量，而不是對韌性材料的屈服應力，因為卸載橡膠材料時幾乎沒有（如果有的話）永久壓痕。 |
| Rupture stress | 斷裂應力 |
The stress at failure. Also known as breaking stress. 失效時的應力。也稱為破裂應力。 |