1、考試必備(1)Engine lathes(1)普通車床(2)Toolroom lathes(2)萬能車床(3)Turret lathes(3)轉(zhuǎn)塔車床(4)Vertical turning and boring mills(4)立式車床(5)Automatic lathes(5)自動(dòng)車床(6)Special-purpose lathes(6)特殊車床A bilateral tolerance is one where the tolerance range is disposed on both sides of the nominal dimension. 雙向公差是在公稱尺寸兩側(cè)都有公差帶

2、的公差。A bulk of the remaining sand and cores can be removed by mechanically striking the part. 大量的剩余型砂和砂芯要通過機(jī)械敲擊零件來去除。A ceramic is often broadly defined as any inorganic nonmetallic material陶瓷通常被概括地定義為無機(jī)的非金屬材料。A chip is variable both in size and shape in actual manufacturing practice. 在實(shí)際加工過程中切屑的尺寸和形狀

3、都是變化的。A compaction stage is typically used to ensure good coverage and solid molds. 通常要采取壓緊步驟來保證良好的覆蓋和堅(jiān)固的鑄型。A distinction may be made between open-die forging, usually in the form of hammer forging, and closed-die forging. 錘鍛中常用的開式模鍛與閉式模鍛是有區(qū)別的。A drill jig is a device for ensuring that a hole to be d

4、rilled, tapped, or reamed in a workpiece will be machined in the proper place.鉆模是一種確保在工件正確位置進(jìn)行鉆孔、攻絲或鉸孔加工的裝置。A fixture holds the work during machining operations but does not contain special arrangements for guiding the cutting tool ,as drill jigs do.夾具在機(jī)加工作業(yè)時(shí)夾持工件，但它不象鉆模那樣包含引導(dǎo)切削刀具的特殊布置。A football pla

5、yer counts on this when he trusts that his facemask wont shatter.橄欖球運(yùn)動(dòng)員據(jù)此相信他的面罩不會(huì)裂成碎片。A forged metal can result in the following: 鍛造金屬可以導(dǎo)致下列結(jié)果：A glass is an inorganic nonmetallic material that does not have a crystalline structure. 玻璃是沒有晶體狀結(jié)構(gòu)的無機(jī)非金屬材料。A good procedure to follow is to heat-quench a nu

6、mber of small specimens of the steel at various temperatures and observe the result, either by hardness testing or by microscopic examination. 要遵循的合適步驟是將這種鋼的一些小試件加熱到不同的溫度后淬火，再通過硬度試驗(yàn)或顯微鏡檢查觀測結(jié)果。A hole in the body acts as a conduit to transmit coolant under considerable pressure to the tip of the drill

7、.鉆頭體中有個(gè)孔作為導(dǎo)管在相當(dāng)大的壓力下將冷卻液傳送到鉆頭頂端。A host of suppliers of auxiliary equipment, molds, instruments, and controls service this major segment of the polymer industry許多輔助設(shè)備、模具、儀器和控制系統(tǒng)供應(yīng)商在為聚合物工業(yè)的這一主要部分服務(wù)。A large majority (above 80%) of all the machine tools used in the manufacturing industry have undergone

8、metal cutting. (2) 用于制造業(yè)的全部機(jī)床中的大多數(shù)(多于80%)都經(jīng)歷過金屬切削。A large variety of cutting tool materials has been developed to cater to the variety of materials used in these programmes. 多種切削刀具材料被開發(fā)出來以滿足這些方案中使用材料的多樣性。A lathe is a machine tool used primarily for producing surfaces of revolution and flat edges.車床是

9、主要用于生成旋轉(zhuǎn)表面和平整邊緣的機(jī)床。A machine with a 10,000-ton capacity has been built to mold 264-gallon HDPE trash containers. 一臺(tái)能力為10,000噸用于成型264加侖高密度聚乙烯垃圾箱的機(jī)械也已制成。 A machining (finish) allowance is made for this type of defect. 對這類缺陷采用機(jī)加工(最后一道工序)的余量。A modern lathe usually has a quick-change gearbox located unde

10、r the headstock and driven from the spindle through a train of gears. 現(xiàn)代車床一般在主軸箱下裝備快速變換齒輪箱，通過一系列齒輪由主軸驅(qū)動(dòng)。A number of attempts have been made in understanding the metal cutting process and using this knowledge to help improve manufacturing operations which involved metal cutting. 在了解金屬切削過程并運(yùn)用這些知識(shí)幫助改善與

11、金屬切削有關(guān)的制造作業(yè)方面已經(jīng)做了許多努力。A number of developments have occurred in the current century. 在最近的百年里產(chǎn)生了許多進(jìn)展。A part has many voids that can be impregnated. 零件有許多可供填充的空間。 A part surface can be infiltrated with a low melting point metal to increase density, strength, hardness, ductility and impact resistance.P

12、lating, heat treating and machining operations can also be used.零件表面能被低熔點(diǎn)金屬滲透以增大密度、強(qiáng)度、硬度、延展性和抗沖擊能力。仍然可以進(jìn)行電鍍、熱處理和機(jī)加工作業(yè)。A piece of hot metal sufficient to slightly overfill the die shape is placed in the bottom die, and the top die is forced against it, so that the metal takes the internal shape of th

13、e die. 將一塊大小足以充填模腔并能稍有溢出的加熱金屬放入底模，并將頂模加壓合攏，這塊金屬便獲得該模腔的形狀。A polymer has a repeating structure, usually based on a carbon backbone. 聚合物具有一般是基于碳鏈的重復(fù)結(jié)構(gòu)。A proper lubricant is necessary for making good forgings. 制造良好的鍛件必須有合適的滑潤劑。A range of atmospheres, including vacuum, are used to sinter different materi

14、als depending on their chemical compositions. 根據(jù)不同材料的化學(xué)成分，燒結(jié)的環(huán)境包括真空狀態(tài)也各不相同。A reciprocating screw injection molding machine combines the functions of an extruder and a compressive molding press.往復(fù)螺旋注射成型機(jī)把壓出機(jī)和成型壓力機(jī)的功能結(jié)合起來。A riser is an extra void created in the mold to contain excessive molten materia

15、l. 冒口是在鑄模內(nèi)部增加的額外空間，用于容納過多的熔化金屬。A Second pressing operation, repressing, can be done prior to sintering to improve the compaction and the material properties.在燒結(jié)前可以進(jìn)行二次擠壓作業(yè)(再擠壓)以改善壓實(shí)狀態(tài)和材料性能。A shaft might have a nominal size of 2.5in.(63.5mm), but for practical reasons this figure could not be maintai

16、ned in manufacturing without great cost. 一根軸可能的名義尺寸為2.5in.(63.5mm)，但由于實(shí)際原因不用大成本是不能在制造中保持這個(gè)數(shù)字的，因此要增加確定的公差。 A similar technique is to “glue” the small percentage of alloying element onto the iron powder. 另一種類似的技術(shù)是把小百分比的合金元素“粘合”到鐵微粒上。A simplified diagram, such as the one in Fig.2.1, focuses on the eute

17、ctoid region and is quite useful in understanding the properties and processing of steel. 如圖2.1所示的簡化鐵碳狀態(tài)圖將焦點(diǎn)集中在共析區(qū)，這對理解鋼的性能和處理是十分有用的。A Simplified Iron-carbon Diagram簡化鐵碳狀態(tài)圖A single full turn of the workpiece generates a circle whose center falls on the lathe axis; this motion is then reproduced nume

18、rous times as a result of the axial feed motion of the tool.工件旋轉(zhuǎn)一整圈產(chǎn)生一個(gè)圓心落在車床主軸上的圓；由于刀具的軸向進(jìn)給運(yùn)動(dòng)這種動(dòng)作重復(fù)許多次。A steel with varying carbon content and, consequently, different critical temperatures requires a special heat treatment. 含碳量變化的鋼具有不同的臨界溫度，因此需要特殊的熱處理。A substantial precipitation of cementite begin

19、s at 600(315), which produces a decrease in hardness. 滲碳體的大量析出開始于600(315)，這使硬度下降。A system of tolerances is necessary to allow for the variations in accuracy that are bound to occur during manufacture, and still provide for interchangeability and correct function of the part.為了允許在制造過程中必然會(huì)發(fā)生的精度變化，并提供零

20、件的互換性和正確功能，一個(gè)公差系統(tǒng)是必需的。A third tempering treatment may be used to reduce strains.第三次回火處理可用于減少應(yīng)變。A tolerance is the difference in a dimension in order to allow for unavoidable imperfections in workmanship. 公差是為了允許工藝上不可避免缺陷而存在的尺寸上的不同。 A typical cutting tool in simplified form is shown in Fig.7.1. The i

21、mportant features to be observed are follows. 典型切削刀具的簡化形式如圖7.1所示。要注意的重要特征如下A unilateral tolerance is one where the tolerance zone is on one side only of the nominal dimension, in which case the nominal dimension may form one of the limits.單向公差是僅在公稱尺寸一側(cè)有公差帶的公差，在這種情況下公稱尺寸成了兩個(gè)極限中的一個(gè)。A variation from th

22、is type is planetary internal grinding, which is recommended for heavy workpieces that cannot be held in chucks. 這種方法的一個(gè)變體是行星式內(nèi)表面磨削，當(dāng)工件較重不能用卡盤固定時(shí)推薦使用。A very large clearance angle reduces the strength of the tool tip, and hence normally an angle of the order of 56is used.很大的后角會(huì)削弱刀尖的強(qiáng)度，因此一般采用56的后角。A w

23、ide variety of milling cutters is available in industry. 工業(yè)上可采用的銑刀類型眾多。Above this point the hardness can be increased only slightly, because steels above the eutectoid point are made up entirely of pearlite and cementite in the annealed state. 高于此點(diǎn)，由于超過共析點(diǎn)鋼完全由珠光體和退火狀態(tài)的滲碳體組成，硬度增加并不多。Abrasive disks fo

24、r cutoff and slotting operations. (thickness 0.02 up to 0.2in. (0.5 to 5mm). 4)用于切斷和開槽作業(yè)的砂輪片(其厚度從0.02到0.2英寸(0.5到5毫米)。According to the procedure used, steel can be hardened to resist cutting action and abrasion, or it can be softened to permit machining. 按所采用的步驟，鋼可以通過硬化來抵抗切削和磨損，也可以通過軟化來允許機(jī)加工。Accuracy

25、 is ensured by machining suitable location features as early as possible, and using them for all location, unless other considerations mean that other location features must be used. 除非有必要采用另外定位要素的其它考慮，精度可通過盡可能早地加工合適的定位要素并采用它們進(jìn)行所有定位來保證。Actually, analysis of photomicrographs shows that this built-up

26、edge is held in place by the static friction force until it becomes so large that the external forces acting on it cause it to dislodge, with some of it remaining on the machined surface and the rest passing off on the back side of the chip, Fig.7.3c. 實(shí)際上，對顯微照片的分析顯示這種切屑瘤受到靜摩擦力抑制直至它變得大到作用在它上面的外力使其移動(dòng)，

27、一些留在機(jī)加工表面上而另一些延伸到切屑的背面，見圖7.3c。Adding other metals can affect the density, strength, fracture toughness, plastic deformation, electrical conductivity and environmental degradation.加一些其它金屬能影響密度、強(qiáng)度、斷裂韌性、塑性變形、導(dǎo)電性以及環(huán)境侵蝕。Additional tables give the values for basic sizes above 500 mm and for “Commonly Used

28、 Shafts and Holes” in two categories“General Purpose” and “Fine Mechanisms and Horology”.對基本尺寸大于500毫米和在“一般用途”和“精密機(jī)械和鐘表”兩個(gè)類別中的“常用的軸和孔”而言，由附加的表格給出數(shù)值。Additionally there are extensions to the gating system called vents that provide the path for the built-up gases and the displaced air to vent to the atm

29、osphere. 除此之外，還有稱為排放口的澆注系統(tǒng)延長段，它為合成氣體和置換空氣排放到大氣提供通道。Advantages優(yōu)點(diǎn)After compaction the components pass through a sintering furnace. 零件壓實(shí)后通過燒結(jié)爐。After injection moulding, the plastic binder material is removed to leave a metal skeleton which is then sintered at high temperature. 注塑成型后，去除塑料粘合材料剩下金屬骨架，然后在高

30、溫下燒結(jié)。After the workpiece has been marked out, it is still necessary to position it with respect to the machine movements, and to clamp it in that position before machining is started.工件劃線后，仍有必要將其相對于切削運(yùn)動(dòng)定位，并在機(jī)加工開始前把它裝夾到位。After this, the entire pattern is placed in an oven and the wax is melted away.

31、完成后把整個(gè)型模放在烤箱里融化石蠟。Again, at economical working pressures, products are not fully dense and usually need additional working such as hot extrusion, hot rolling or forging to fully density the material.此外使用經(jīng)濟(jì)工作壓力的產(chǎn)品不是充分致密的，一般需要增加諸如熱擠壓、熱軋或鍛之類的額外工序來使材料達(dá)到全密度。Again, recommended values for feeds, which can

32、be taken as guidelines, are found in handbooks and in information booklets provided by cutting tool manufacturers.再者，作為指導(dǎo)方針的進(jìn)給推薦值可以從手冊和切削刀具生產(chǎn)商提供的資料小冊子上找到。Alignment pins may also be used for mating the molds later. 為了以后鑄模匹配還要用到定位銷。All dimensions must be governed by the general tolerance on the drawin

33、g unless otherwise stated. 除非另行說明，所有尺寸都必須受圖上的通用公差控制。All these characteristics may not be found in a single tool material. Improved tool materials have been giving a better cutting performance. 所有這些特性不可能存在于單一刀具材料中。改進(jìn)的刀具材料已經(jīng)被賦予較好的切削性能。Allowance, which is sometimes confused with tolerance, has an altog

34、ether different meaning. 允差，有時(shí)會(huì)跟公差混淆，但其具有完全不同的含義。 Alloy steel owe their properties to the presence of one or more elements other than carbon, namely nickel, chromium, manganese, molybdenum, tungsten, silicon, vanadium, and copper. 合金鋼的性質(zhì)取決于其所含有的除碳以外的一種或多種元素，如鎳、鉻、錳、鉬、鎢、硅、釩和銅。Alloys are compounds cons

35、isting of more than one metal. 合金是由一種以上金屬組成的混合物。Alloys contain more than one metallic element. 合金包含不止一種金屬元素。Also coating operations such as plating or painting are straightforward due to a good surface, which needs very little preparation. 另外由于鍛件良好的表面，像電鍍或油漆之類的涂裝工序就很簡單，幾乎不需要做準(zhǔn)備工作。Also, adding some c

36、hromium to steel will slow the rusting process, but will make it more brittle.同樣，在鋼里加一些鉻能減緩它的生銹過程，但也將使它更脆。Also, that hole has a tapered surface to allow mounting a plain lathe center. 同時(shí)，此孔為錐形表面可以安裝普通車床頂尖。Also, the grinding action in this case is achieved by the end face of the grinding wheel (Fig.8

37、.1b), contrary to the case of horizontal-spindle machines, where the workpieces ground by the periphery of the grinding wheel. 而且在這種情況下，磨削動(dòng)作是通過砂輪端面完成的(圖8.1b)，這與通過砂輪周邊磨削工件的臥式主軸磨床正好相反。 Also, the plane angles of these tools must always be identical to those of the thread forms. 同時(shí)，這些刀具的平面角必須始終與螺紋形狀的平面角

38、保持一致。Altering the Surfaces改變表面Although most of the softening action occurs in the first few minutes after the temperature is reached, there is some additional reduction in hardness if the temperature is maintained for a prolonged time. 雖然大多數(shù)軟化作用發(fā)生在達(dá)到所需溫度后的最初幾分鐘，但如果此溫度維持一段延長時(shí)間，仍會(huì)有些額外的硬度下降。Although sm

39、all tolerances give higher quality work and a better operating mechanism, the cost of manufacture increases rapidly as the tolerances are reduced, as indicated by the typical curve of Fig14.1. 雖然較小公差能得到較高加工質(zhì)量和較好操作機(jī)構(gòu)，但隨著公差的減小制造成本會(huì)迅速增加，如圖14.1的典型曲線所示。Although the hydraulic forging press is a more expen

40、sive piece of equipment than a drop-forge, it has advantages beside those of giving greater strength and more uniform structure to large components. 雖然這種液壓鍛機(jī)比落錘鍛造要昂貴得多，但它除了能給予大零件較高的強(qiáng)度和更均勻的組織外還有其它優(yōu)點(diǎn)。Although this process softens steel, it differs considerably from annealing in that the process lends

41、itself to close control of the physical properties and in most cases does not soften the steel to the extent that annealing would. 雖然這過程使鋼軟化，但它與退火是大不相同的，因?yàn)榛鼗疬m合于嚴(yán)格控制物理性能并在大多數(shù)情況下不會(huì)把鋼軟化到退火那種程度。Aluminum in the range of 1% to 1.5% has proved to be especially suitable in steel, in that it combines with th

42、e gas to form a very stable and hard constituent. 在鋼中含鋁1%到1.5%被證明特別合適，它能與氨氣結(jié)合形成很穩(wěn)定堅(jiān)固的成分。An advantage of carbonitriding is that the hardenability of the case is significantly increased when nitrogen is added, permitting the use of low-cost steels.碳氮共滲的優(yōu)點(diǎn)之一是加入氮后外層的淬透性極大增加，為使用低價(jià)鋼提供條件。An analogy car, be

43、 made to a block of ice that can be softened (i.e. turned back to liquid), poured into any shape cavity, and then cooled to become a solid again.一輛由冰塊制成的模擬汽車，可以融化(即轉(zhuǎn)化為液態(tài))，倒入任何形狀的空腔，然后冷卻重新變成固體。An elevated temperature diffusion process referred to as sintering, sometimes assisted by external pressure,

44、 accomplishes this. 提升溫度擴(kuò)散工藝被稱為燒結(jié)，有時(shí)還輔之以外界的壓力來達(dá)到目的。An estimate showed that about 10 to 15% of all the metal produced in USA was converted into chips. (3) 有估計(jì)顯示美國生產(chǎn)的所有金屬中約10到15%轉(zhuǎn)變成了切屑。An example of particle-reinforced composites is an automobile tire which has carbon black particles in a matrix of po

45、lyisobutylene elastomeric polymer.微粒加強(qiáng)型復(fù)合材料的一個(gè)例子是機(jī)動(dòng)車胎，它就是在聚異丁烯人造橡膠聚合物基材中加入了碳黑微粒。An HSS tool is usually made in the form of a single piece, contrary to cemented carbides or ceramic, which are made in the form of tips. 高速鋼刀具通常以單件形式制造，而硬質(zhì)合金或陶瓷刀具則以刀尖形式制造。An optical fiber contains three layers: a core ma

46、de of highly pure glass with a high refractive index for the light to travel, a middle layer of glass with a lower refractive index known as the cladding which protects the core glass from scratches and other surface imperfections, and an out polymer jacket to protect the fiber from damage. 光導(dǎo)纖維有三層：

47、核心由高折射指數(shù)高純光傳輸玻璃制成，中間層為低折射指數(shù)玻璃，是保護(hù)核心玻璃表面不被擦傷和完整性不被破壞的所謂覆層，外層是聚合物護(hù)套，用于保護(hù)光導(dǎo)纖維不受損。And cleaning operations may be used to remove oxides, etc. 可能還要用清洗作業(yè)去除氧化物等。and components can be produced with dimensions that need little or no rectification to meet the dimensional tolerances. 所以零件尺寸幾乎無需校正就能滿足尺寸公差。Angle

48、milling cutter. An angle milling cutter is employed in cutting dovetail grooves, ratchet wheels, and the like. Fig.12.4e indicates a milling cutter of this type.傾斜銑刀：傾斜銑刀用于切削燕尾槽、棘輪之類的。圖12.4e顯示了這類銑刀。Annealing also relieves internal stresses previously set up in the metal.退火也釋放了先前在金屬中的內(nèi)應(yīng)力。Annealing 退火

49、Another advantage is that skilled workers are not required when jigs are used. 另一個(gè)優(yōu)點(diǎn)是采用鉆模時(shí)不需要熟練工人。Any carbon-rich gas with ammonia can be used. The wear-resistant case produced ranges from 0.003 to 0.030 inch(0.08 0.76mm) in thickness. 可以使用任何富碳?xì)怏w加氨氣，能生成厚度從0.003到0.030英寸(0.08 0.76mm)的耐磨外層。Any desired

50、depth of cut can be obtained by the cross feed of the grinding wheel. 通過砂輪的橫向進(jìn)給能得到任意所需的切削深度Any point on the parting surface should be less than 75from the principal parting plane. 分模面上任意點(diǎn)與主分模面的夾角應(yīng)小于75。application of cutting fluid(3)切削液的運(yùn)用ARCA pair of wires are electrically energized so that an arc i

51、s struck across the tips when brought together through a pistol. 電弧噴涂當(dāng)一對金屬絲通過手持噴槍連到一起時(shí)，通上電橫過其末端劃燃電弧。As a general rule both mechanical and physical properties improve with increasing density. 作為普遍規(guī)律，隨著密度的增加機(jī)械和物理性能均改善。As a replenishment for these deposited ions, the metal from the anode is dissolved a

52、nd goes into the solution and balances the ionic potential.作為這些沉淀離子的補(bǔ)充，來自陽極的金屬被溶解并進(jìn)入溶液平衡離子勢能。As an example, precise atmosphere control allows iron/carbon materials to be produced with specific carbon compositions and mechanical properties.例如精確的環(huán)境控制可使鐵/碳材料生成特殊碳化物和機(jī)械性能。As before, any remaining austeni

53、te transforms to pearlite upon slow cooling through this temperature.就像以前說的一樣，當(dāng)緩慢冷卻到這溫度時(shí)所有剩余奧氏體轉(zhuǎn)化為珠光體。As can be seen in Fig.12.1, the two cutting edges are referred to as the lips, and are connected together by a wedge, which is a chisel-like edge. 如圖12.1所示，兩條切削刃就是鉆唇，通過鑿子狀邊緣的楔形體連在一起。As can be seen i

54、n Fig.8.4, the axis of the regulating wheel is tilted at a slight angle with the axis of the grinding wheel. 正如在圖8.4中所看到的那樣，調(diào)節(jié)輪的軸與砂輪軸傾斜一個(gè)微小角度。As engineers, we usually design materials so that they dont deform under normal conditions. 作為工程師，設(shè)計(jì)時(shí)通常要使材料在正常條件下不變形。As far as the direction of cutter rotatio

55、n and workpiece feed are concerned, milling is performed by either of the following two methods. 至于涉及到銑刀轉(zhuǎn)動(dòng)的方向和工件的進(jìn)給，銑削可以通過下列兩種方法之一進(jìn)行。As in most forming processes, use of undercuts should be avoided as these will make the removal of the part difficult, if not impossible. 如同大多數(shù)成型工藝，如果不是非用不可，盡量避免采用凹槽，因

56、為凹槽會(huì)使零件難以取出。As ingots of steel weighing 30 tonnes or more are forged in this way, manual operation is impossible and it is essential that all the manipulation of the ingot is done mechanically. 由于這種情況下被鍛鋼坯重量大于30噸，人工操作是不可能的，鋼坯的所有操作都必須是機(jī)械化的。As injection pressures are low it is possible to manufacture

57、complex components, even some with internal screw threads, by the use of side cores and split tools.注塑壓力較低使得制作復(fù)雜零件成為可能，通過采用側(cè)面型芯和分離工具甚至可以帶有內(nèi)螺紋。As is the case with the plain cutter, the cutting teeth can be straight or helical.象平面銑刀的情況一樣，切削齒既可以是直的也可以是螺旋的。As previously mentioned, the axial feed is auto

58、matically generated when cutting a thread by means of the lead screw, which drives the carriage. 如前所述，當(dāng)依靠驅(qū)動(dòng)大拖板的絲桿切削螺紋時(shí)軸向進(jìn)給是自動(dòng)產(chǎn)生的。As shown in Fig.12.4d, it is quite similar to the plain milling cutter, the difference being that this type has teeth on the sides. 正如圖12.4d所示，它與平面銑刀十分相似，差別在于此類銑刀齒在側(cè)面。As s

59、hown in Fig.4.2, grain flow is the direction of the pattern that the crystals take during plastic deformation. 如圖4.2所示，晶粒流動(dòng)的方向就是在塑性變形期間結(jié)晶排列的方向。As the carbon content in steel increases up to around 0.60%, the possible hardness obtainable also increases. 隨著鋼的含碳量增加到大約0.60%，可能得到的硬度也增加。As the carbon-rich phase forms