制造工程与技术(热加工)英文版14 Forging of Metals

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制造工程与技术(热加工)英文版joining processes and equipment(2)

③ It is used extensively for the joining of plastics, in packaging with foils（箔） and for the lap welding of sheet, foil, and thin wire.
28.4 Friction Welding (FRW) 摩擦焊
④ Welding flash, can easily be removed（容易清除） by machining or grinding.
⑤ FRW machines are fully automated, and the operator skill required is minimal.
Other Friction Welding Processes
Process capabilities:
① The ultrasonic welding process is versatile and reliable. ② It can be used with a wide variety of metallic (ductile) and nonmetallic materials, including dissimilar metals. battery assembly solar energy converter
After sufficient contact is established, the rotating member is brought to a quick stop (so that the weld is not destroyed by shearing ), while the axial force is increased. Oxides and other contaminants at the interface are removed by the radially outward movement（径向排除） of the hot metal at the interface. The pressure at the interface and the resulting friction produce sufficient heat for a strong joint to form. The shape of the welded joint depends on the rotational speed and on the axial pressure applied. These factors must be controlled to obtain a uniformly strong joint.

14Heat treatment

The process curve of normalizing of 45# steel
Heat Treatment
Illustration of Quenching Treatment
淬火(quenching)将工件加热到临界温度(critical temperature)以上，保温(holding)一段时间，在水、油或其它无机盐、有机溶液等淬冷介质中快速冷却(rapid cooling),钢件变硬，耐磨性好，但变脆。
Lesson 14 Heat Treatment
The chemical compositions of the steel, the size and shape of the product, and the properties desired are important factors in determining which of the following production cycles to use.
Lesson 14 Heat Treatment
Hardening is the heating and quenching of certain iron-base alloys from a temperature either within or above the critical temperature range. The temperature of the heat treatment and the length of time at temperature, or “soaking period”, depend upon the composition of the material. The quenching media used may depend upon the composition, hardness desired, and the complexity of the design.

制造工程与技术(热加工)英文版13 Rolling of Metals

Chapter 13 Rolling of Metals（金属的轧制）•13.1Introduction•13.2Flat Rolling•13.3Flat Rolling Practice•13.4 Rolling Mills•13.5Shape-Rolling Operations•13.6 Production of Seamless Pipe and Tubing•13.7 Continuous Casting and Rolling Integrated Mills and Minimills13.1 Introduction•Rolling（轧制）–the process of reducing the thickness (orchanging the cross-section（横截面）) ofa long workpiece by compressive forcesapplied through a set of rolls（轧辊）.Øaccounts for about 90% of all produced by metalworking processesØfirst development in the late 1500sØsimilar to the rolling of dough（面团）with a rolling pin（擀面杖/擀面棍）Rolls （轧辊）Classification of Rolling •By productØflat rolling（平板轧制）Øshape rolling（型材轧制）Øtube rolling（轧管）•By temperatureØhot rolling （热轧）Øcold rolling（冷轧）Flatrollingreduce the thicknessShaperollingchange the cross-sectionFigure 13.1 Schematic outline of various flat-and shape-rolling processes. Source:American Iron and Steel Institute.13.2 Flat RollingA strip（带料/条料）of thickness h o enters the roll gap（辊缝/辊隙/辊间距离）and is reduced to thickness h f by a pair of rotating rolls, each roll being powered through its own shaft by electric motors（电动机）.thickness ＞6 mm Øplate: Øsheet:厚板thickness ≤ 6 mmProduction of Flat Rolling薄板•strip （条料/带料）•strip in coil （卷料/卷材）•machine structures•ship hulls （船体）•boilers （锅炉）•bridges•nuclear vessels （核反应容器）•battleships and tanks : 300mm (12in.) thick : 150mm (6 in.) thick : 100～125mm thick•automobile bodies•aircraft fuselages （机身）•appliances （用具/器具）•kitchen and office equipment •food and beverages container •aluminum foil （铝箔）: 1.8 ～1.9 mm thick : 0.1 mm thick : 0.008 mm (8μm) thickFlat Rolling Process辊间距离/轧辊开度•the thickness is reduced: △h = h o–h f •the length is increased: △l = l f–l o •the width is increased: △w = w f –w o 压下量延伸量宽展量V o:the velocity of the strip at the entrance（入口）V f:the velocity of the strip at the exit（出口）V r:the surface speed of the rolls ,which is constant（不变的）V0 < V fV0 < V r< V fThere is relative sliding（相对滑动）between the rolland the strip along the arc ofcontact in the roll gap, L.Definition: One point along the contact length, whereV s :the velocity of the strip,which is variable during thecourse of rollingV r :the surface speed of the rolls,which is constant while rollingNeutral Point or No-Slip Point（中性点/无滑移点）V s = V r13.2.1 Frictional Forces（摩擦力）•Since there is relative sliding between the roll and the strip along the arc of contact in the roll gap, the frictional forces, which oppose motion, act on the strip.Fig13.2 (b) Friction forces acting on strip surfacesØThe rolls pull the material into the roll gap through a net frictional force （净摩擦力）on the material.Øis necessary for rolling materials.Significance （重要性/意义）of Friction what ’s thedirection of net frictional force?“咬入”Disadvantage of FrictionØEnergy is dissipated（浪费）in overcoming friction; thus, increasing friction means increasing forces and power（功率）requirements.Øcould damage（损害）the surface of the rolled product.A compromise（折衷/妥协）has to be made, onewhich includes low coefficients of friction（摩擦系数）by using effective lubrication（润滑）.Max Draft（最大压下量）•reduction in thickness, △hh0-h f = µ2RμRdraftμ: the coefficient of the frictionR: the roll radius13.2.2 Roll Force and Power RequirementRoll Force （轧制力）Power （功率）per roll 18L : the roll-strip length of contact arc w : the width of the stripY avg : the average true stress （平均真实应力）T: torqueω : angle speed轧制力矩/扭矩n: revolutions （转数）per second of the roll N: rpm (revolutions perminute) of the rollavg F LwY = (/2)(2) /60 W /60000 W /33000 P T F L n FLN FLN k FLN hp ωππππ==⋅===W: watt （瓦特）k W ：kilowatthp ：horsepower （马力）Four-high Rolling-mill （四辊轧机）Figure 13.3 Schematic illustration of a four-high rolling-mill stand （轧机机座）, showing its various features. The stiffnesses （刚度）of the housing, the rolls, and the roll bearings are all important in controlling and maintaining the thickness of the rolled strip.机架轴承座/底座支撑辊支撑辊工作辊螺杆或液压机构Too high roll force cancause the rolls:Ødeflection （挠度/弯曲）Øflattening （压扁）a.reducing friction, μ;ing smaller diameter rolls, R , to reduce the contact area;c.taking smaller reductions per pass, Δh , to reduce the contact area;d.rolling at elevated temperature , to lower the strength（强度）to the material.L ≈2h Rµ∆=20 a v gF L w Y =Reducing Roll Forces• e. applying longitudinal tensions（纵向拉力）to the strip during rolling.–As a result, the compressive stresses required to deform thematerial plastically become smaller–particularly important in rolling high-strength metal–Tensions can be applied at the entry zone (back tension) （后拉力/后张力）, by applying a braking action（制动）to thereel which supplies the sheet to the roll gap (the pay-off reel)（开卷机）, by some suitable means.–Tensions can also be applied at the exit zone (front tension)（前拉力/前张力）, by increasing the rotational speed of thetake-up reel（卷取机）.–Steckel rolling（斯特克尔轧制法）: be carried out by fronttension only, with no power supplied to the rolls开卷机/松卷机13.2.3 Geometric Considerationsa.Roll bending （轧辊弯曲）b.Thermal camber of rolls（轧辊热挠度）c.Flattening of rolls（轧辊压扁）d.Spreading of strip（条料展宽）Methods:1)the higher elastic modulus （弹性模量）of the roll material, the smaller the roll deflection （轧辊挠度）2)roll camber （轧辊凸度）: grinding the rolls so that their diameter at the center is slightly larger than at their edges.3)application of moments （力矩/Roll Bending （轧辊弯曲）Figure 13.4 (a) Bending of straight cylindrical rolls, caused by the roll force. (b) Bending of rolls ground with camber （凸度）, producing a Crown （隆起）Results:the rolled strip tends to be thicker at its center than at its edges. Reasons:roll forces tend to bend the rolls elastically （弹性地）•Application of moments（弯矩）at their bearings–通过加在辊体两端的反力矩来平衡轧辊两端工作压力产生的弯矩，减小轧辊的变形Thermal Camber （热挠度）Results:can produce strips that are thinner at the center than at the edges.Methods:the total (or final) camber can be controlled by varying the location of the coolant （冷却液/冷却剂）on the rolls during hot rolling.Reasons:the rolls becomes slightly barrel-shaped （鼓形/桶形）because of the heat generated by plastic deformation （塑性变形）during rolling.rollstripFlattening of Rolls （轧辊压扁）Results:It produces a larger roll radius and a larger contact area for the same draft. The roll force in turn, increases with increased flattening.Methods:enhancing the strength of roll materials or the radius of the rollReasons:elastic deformation caused by roll forcesSpreading of a Strip （条料展宽）Figure 13.5 Increase in the width (spreading) of a strip in flat rolling (see also Fig. 13.2a). Similarly, spreading can be observed when Phenomenon:–For strip with high w 0/h 0ratios , the width of the material remains effectively constant after rolling.–For strip with smaller w 0/h 0ratios , the width increases considerably in the roll gap.Spreading :–increase in widthMethods:use of vertical rolls in contact with the edges of the rolled product (edging rolling ) （立轧/轧边）Influence Factors of SpreadingSpreadingfrictionR/h 0ratiow 0/h 0ratio(width constraint )(longitudinal constraint )13.3 FLAT-ROLLING PRACTICE1.Hot Rolling （热轧/初轧）—done above the recrystallization temperature（再结晶温度）Figure 13.6 Changes in the grain structure of cast or of large-grain wrought metals during hot rolling.cast structure wrought structuredendritic（树枝状的）coarse（粗大的）nonuniform grains（不均匀的晶粒）brittle（脆/脆性的）porous（多孔的）equal/uniform grain(等轴晶) finer (细化的)enhanced ductility(韧性好的) non-porosity(无孔)wrought structure（锻造组织）cast structure （铸造组织）Advantages of Hot Rolling•reduce grain size•improve strength and ductility（塑性/延展性/柔韧性）–breaking up（破裂/打碎）brittle grain boundaries （晶界）–closing up（压合/压实）internal defects（内部缺陷）, especially porosity （多孔性）Temperature of Hot RollingThe temperature for hot rolling varies with different metals.•aluminum (Al) alloys（铝合金）: about 450℃(850℉) •alloy steels（合金钢）: 1250℃(2300℉) •refractory alloys（高温合金/难熔合金）:1650 ℃(3000℉)•slab •bloom •billet Products of the First Hot-rolling OperationØrectangular in cross-section （矩形截面）Ørolled into plates and sheets laterØhas a square （正方形）cross-sectionØat least 150mm on the sideØprocessed further, by shaping rolling, intostructure shapes, such as I-beams （工字梁）and railroad railsØsquare Øwith a cross-section area smaller than blooms Ørolled into various shapes, such as round rods （圆棒）and bars （杆材）, by the use of shaped rolls扁坯小方坯大方坯连续铸件或铸锭圆管坯wire rod 盘条无缝钢管焊接钢管制管钢板酸洗和润滑结构型材钢轨HotrollingDefect（缺陷）in Hot Rolling•Scale（氧化皮/氧化垢）：consisting mainly of the oxides（氧化物）Conditioning（清理/处理）Methods •using a torch（气炬）( scarfing 火焰表面清理）•pickling with acids （acid etching，酸洗/酸蚀）•by such mechanical means as blasting with water（喷水）•grinding（研磨）•better surface finish （表面光洁度）•better dimensional tolerances （尺寸公差）•enhanced mechanical properties （机械性能）Advantages of Cold Rolling2.Cold Rolling （冷轧）—carried out at room temperature （室温）because of lack of scale due to strain hardening（应变硬化）without thermal expansion3.Pack Rolling （迭板轧制）—two or more layers of metal are rolled together, which improves productivity（生产率）.Example: Aluminum Foils•pack rolled in two layers•foil-to-foil side: matte（无光泽的）•foil-to-roll side: shiny（光亮的）and bright •reason: contact with the polished（抛光的）rolls ?satiny（光滑的）finish4. Temper Rolling or Skin Pass（硬化冷轧或表面光轧）-the steel metal is subjected to a final light rolling pass（工步）of 0.5% to 1.5% reduction-produce compressive residual stress（残余压应力）onthe surfaceReason:•For mild steel（低碳钢/软钢）, when stretched during sheet-forming operations, undergoes yield-point elongation（屈服点延伸）, a phenomenon that causes surface irregularities（不整齐）called stretcher strains（拉伸应变纹）or Lueder’s bands（吕德38斯带）( Section 16.3).5. Levelling Rolls（矫直轧）—to improve flatness（平面度/平整度）, the rolled strip is passed through a series of leveling rolls（矫直辊）Figure 13.7 A method of roller levelling to flatten Method:rolled sheets.•Several different roller arrangements are used.•Each roll is usually driven separately, by an individual electric motor.•The strip is flexed（弯曲）in opposite directions as it passes through the sets of rolls.Levelling Rolls•在辊式矫直中，金属板经过不断地交错变形弯曲。

[新版]热加工（英文版）

Molding Powder metallurgy Machining Casting Castability Ceramics UniformityGeometric Ambient temp Alloy ApplicationFinishing Net-shape manufacturing Mechanical property Gating systemSprue Runner Gate Riser Oxide Velocity--viscosityDie Inclusion Wall Subscript Impermeable Incompressible Friction Loss Mass Insoluble particl Index Spiral Shrinkthe gating system (sprue, runners and gates)√10.1 Why is casting an important manufacturing pro cess?√10.9 describe the features of a gating system.√10.16 what is a riser?√10.47 A sprue is 10 in. long and has a diameter of 5 in. at the top, where the metal is poured. If a designed flow rate of 40 in3/sec is to be achieved, what should be the diameter of the bottom of the sprue?expendable-pattern casting一次性模样铸造(lost foam)blank毛坯bead珠、粒pentane戊烷aluminum铝slurry泥浆long production run = large production run polyalkylene聚烯PMMA聚甲基丙烯酸甲酯，（有机玻璃/亚克力Acrylics）poly methyl meth acrylaterefractory难熔的, hot-work die steel, slush = slurry泥浆, large (long) ~ small production runs, sodium钠silicate硅酸盐water glass水玻璃, fin鱼翅,鳍lawnmower割草机,gear齿轮integral完整的prior先copper铜,警察bronze青铜(Cu+锡Sn) brass 黄铜(Cu+锌Zn),horizontal or vertical卧式or立式, plunger活塞, pot, ejector box顶杆框,stationary platen定模板, ladle长柄勺stationary固定的sleeve袖子tendency倾向rate=rank/grade,clamping force合模力, stroke冲程identical相同的～different不同的checking裂缝lubricant润滑剂,flash飞边, knurled滚花bushing轴衬liner衬套，groove = spline开键槽, shaft 轴, popsicle冰棒snow cones雪糕optical 光学的,视力的specimen范例,标本,样品,样本,待试验物ductility延展性mechanical property机械性能extreme 极端flaw瑕疵,裂缝detector探测器sniffer嗅探器investigate研究surfacedestructive and nondestructive test有损与无损探伤pressure tightness, scent气味carry out=do, storage and retrieval systems存取系统pattern &mold making,CAD/CAM: computer aided design and manufacture melt, pour conveyor生产线automation, industrial robot, jobbing a.做零活的safety: fume浓烟crucible坩锅flux熔化hygroscopic吸湿的pyrometer高温计calibration刻度apron围裙,挡板11.1 describe the differences between expendable and permanent molds.11.5 what is the function of a core? What are core prints?11.14 what are parting agents?12.1 list the general design considerations in casting12.3 what is shrinkage allowance? Machining allowance?12.8 name the important factors involved in the economic of casting operationsStapler wrench foil film toaster electrical-resistance hull ball bearing elevator Ingot slab wrought pellet flake ore synthetic work piece stock translucent Beverage insulator spark plug reinforce discrete disk=disc bolt bulk tube polyamide聚酰胺PC= polycarbonate聚碳酸酯酯ester脂fat, grease, rougePE= polyethene聚乙烯PVC= polyvinyl chloride 聚氯乙烯PTFE =Poly tetra fluoro ethylene聚四氟乙烯PP= polypropene聚丙烯PS= polystyrene 聚苯乙烯ABS [汽] anti-skid brake system. 防滑刹车系统[化] Acrylonitrile Butadiene Styrene丙烯腈-丁二烯-苯乙烯PU= polyurethane聚氨酯PMMA=Polymethymethacrylate 聚甲基丙烯酸甲酯Polygram宝丽金(唱片公司)。

制造工程与技术专业英语阅读(一)教案

专业英语阅读（一）教案张新房Part II: Metal-Casting Processes and Equipment金属铸造工艺与设备In this part, some important and fundamental knowledge about casting must be understood. For this chapter, we should know the differences of Chinese meanings for these professional English words, and I will address these important parts.Forming: 成型Molding: 造型Powder metallurgy:粉末冶金Pouring:浇注Ornament:装饰物Intricate: 复杂的Hollow: 中空的Fig. II. 1 Cast parts in a typical automobile 图2.1一个典型的汽车中的铸造部件Water pump: 水泵Pulley: 滑轮Grill: 栅栏Intake and exhaust manifold: 进气和排气管Disk brake: 刹车片Brake drum: 制动鼓Brake cylinder: 闸缸Lettering:编字码Differential housing: 差速机壳Transmission housing: 变速机壳Engine block: 汽缸体Carburetor: 化油器Piston: 阳模Alternator housing: 同步发电机壳Fig. II. 2. Outline of metal-casting processes described in part II.图II.2. 在第二章中所描述的金属铸造工艺概要Chapter 10 Fundamentals of Metal-Casting金属铸造基础For this chapter, it was divided into these parts:1.Introduction: 简介2.Solidification of metals: 金属的凝固3.Fluid flow: 流体流动4.Fluidity of molten metal: 熔融金属的流动性5.Heat transfer: 热传递6.Defects: 缺陷First, 1. IntroductionThe casting process basically involves three steps:a.pouring molten metal into a mold patterned after the part to be manufactured; (把熔融金属浇注到加工好的模具型腔)b.allowing it to cool and solidify （冷却和凝固）c.removing the metal from the mold （从模具中取出金属）As we know, the casting is the oldest process to manufacture part of tool in the human being’s history, because it has many advantages compared with other manufacturedprocesses as follows:✓ complex shapes, such as differential housing (差速机壳) used in the automobile,crankshaft （曲轴） and so on;✓ Very large part, such as engine housing used in the ship making.✓ Utilize the work pieces that other manufactured processes can not produce ofuneconomic, such as turbine blade (涡轮机叶片).So, it is essential for us to understand the fundamentals of metal casting by studying this book hard.There are some important considerations in the casting operation as follows:✧ The flow of the molten metal into the mold cavity: 熔融金属流入模具型腔,Fluidity.✧ The cooling and solidification of metal in the mold: 金属在模具中的冷却和凝固: heat transfer: 热传导.✧ The influence of different type of mold materials, different heat transferringability, 不同的模具材料具有不同的热传导能力.In this part, we talked about some introductions of metal casting; in the next, we will talk the second part: solidification of metals.2. Solidification of metalsAs we know, for different metals, such as pure metals and alloys, the solidification processes are different, so they will be divided into pure metal and alloy to be discussed different solidification processes.1, Pure metalsFor pure metal, the melting point is constant, so, the solidification is like this one:熔化潜热 After reaching melting point solidification from interface and then to center with different grain type and sizeRelease of latentheat of fusionChill zone: 极冷区，白口区，grain size due to very high cooling rate.Columnar zone: 柱状区，large grain size due to lower cooling rate and heterogeneous nucleation.Equiaxed zone: 等轴晶区，homogeneous nucleation.Fig. 10.2. Development of a preferred texture (择优质构) at a cool mold wall. Note that only favorably oriented grains grow away from the surface of the mold.We can see, different metals have different solidified structures, and the nucleationagents affect it.Fig. 10.1 Schematic illustrationof three caster structure ofmetals solidified in a squaremold; a, pure metals; b,solid-solution alloys; c,structured obtained by usingnucleating agents(孕育剂).Fig. 10.3. Schematic illustration ofalloy solidification and temperaturedistribution in the solidifyingmetal. Note the formation ofdendrites in the mushy zone (多空隙的区域).10.2.2 alloysThe solidification process of alloys can be schematically illustrated from Fig. 10.3. From this figure, we can see, the solidification takes place in a temperature range, Tl and Ts. The solidification process of this type alloy can be illustrated as follow:arms and branches.The structure of dendrite influences the properties of casting seriously, so it is essential to find and study the effectors on its structure.As mentioned above, the structure of dendrite is affected by the mushy zone; in other word, it can be described as different mushy zone during solidification, and the mushy zone can be named as freezing range, as this:Fig. 10.4 (a) Solidification patterns for gray cast iron in a 180mm square casting. Note that after 11min. of cooling, dendrites reach each other, but the casting is still mushy throughout. (b) Solidification of carbon steel in sand and chill (metal) molds. Note the difference in solidification patterns as the carbon content increasesFreezing range = Tl-Ts, the temperature difference between Tl and Ts during solidification.For example: for pure metals and eutectic alloys, freezing range = 0, so, no mushy zone, no dendrite formation.Usually, the short freezing range < 50o C, for example, Fe-base alloys.The long range freezing rang > 110o C, example, Al and Mg-base alloys, and these alloys are in a mushy state throughout most of solidification process.Effect of cooling rateThe casting structure is affected seriously by the cooling rate:Usually, for slow cooling rate (<102K/s), coarse dendrite formation;Faster cooling rate (on the order of 104K/s), finer dendrite formation;Higher cooling rate (106~108K/s), amorphous formation.As cooling rate increases, the grain size decreases, so strength and ductility enhanced, that is hall-petch formula.For the solidified structure, it can be certified by the ratio of G/R, where G is thermal gradient at the interface of liquid and solid, and R is the rate at which the liquid-solid interface moves. Typical values for G range from 102 to 103K/m and for R from 10-3 to 10-4m/s. Dendritic type structures ( Figs. 5.5a and b) typically have an ratio in the range of 105 to 107, whereas ratios of 1010 to 1012 produce a plane-front, nondendritic liquid-solid interface (Fig. 10.6).Fig. 10.5. Schematic illustration of three basic types of cast structures: (a) columnar dendritic; (b) equaiaxed dendritic; and (c) equiaxed nondendritic.Fig. 10.6. Schematic of caststructures in (a) plane front,single phase, and (b) plane front,two phases.10.2.3. structure-property relationshipAll castings are hoped to meet design and service requirements. Usually, the property is up to structure. The compositions of dendrites and the liquid metal are given by the phase diagrams of particular alloys, usually binary alloys. As cooling rate very low, dendrite with uniform composition develops. Normal (fast) cooling rate, core dendrites develop with different composition at surface and center, known as concentration gradient (浓度梯度): higher content of alloying element in the surface layer than that of center. That is due to solute rejection during solidified process, resulting in microsegregation (微观偏析).Macrosegregation (宏观偏析) involves differences in composition throughout the casting.Normal segregation (正常偏析), verse segeration (反向偏析), the reason is that liquid metal ( having a higher concentration of alloying elements) enters the cavities developed from solidification shrinkage (收缩) in the dendritic arms which solidified sooner.Gravity segregation (重力偏析) describes the process whereby higher-density inclusions (夹杂) or compositions sink (下沉) and lighter elements (such as antimony in antimony-lead alloy (锑-铅)) float (上浮) to surface.Inoculants (孕育剂) induce the nucleation of the grains throughout the liquid induced heterogeneous nucleation.Convection promotes the formation of an outer chill zone, refines grain size and accelerates the transition from columnar to equiaxed grains.Dendrite multiplication: 枝晶增殖, rheocasting: 流变铸造In this part, we talked about the solidification process for different metals and the property-structure relation; next, the fluid flow will be talked.10.3. Fluid flowThe fluid flow is most important factor in casting. As shown in fig. 10.7, the casting process is described as: the molten metal is poured through a pouring basin (转包，浇注槽) or cup. It then flows through the gating system (浇注系统) (sprue, runners and gates, 注流口, 流道, 内浇道) into the mold cavity. Sprue is a vertical channel through which molten metal flows downward in the mold. Runners are the channels that carry the molten metal from the sprue to the mold cavity, or connect the sprue to the gate. The gate is that portion of the runner through which the molten metal enters the mold cavity. Risers (冒口) serve as reservoirs (储液槽) to supply the molten metal necessary to prevent shrinkage during solidification, as shown in Fig. 10.7.Trap contaminant: 捕获杂质, premature cooling: 过早冷却, gas entrapment: 夹气 Gating system design is the most important part to get high quality castings.Two basic principles of fluid flow are relevant to gating design: Bernoulli`s theorem and law of mass continuity.Bernoulli`s theorem: 百努利定律t cons gv g p h tan 22=++ρ 10.2 Where:h: the elevation above a certain plane, p: pressure at that elevation, v: velocity of the liquid at at elevation, ρ: the density of the fluid, g: gravitational constant.Conservation of energy requires that, at a particular location, in this system, the relationship is satisfied:f g v g p h g v g p h +++=++2222222111ρρ 10.3 Fig. 10.7. Schematic illustrationof a typical riser-gated casting.Risers serve as reservoirs,supplying molten metal to thecasting as it shrinks duringsolidification.Where, subscripts (下标) 1 and 2 represent two different elevations, and f represents the frictional loss in the liquid as it travels downward through the system.Continuity (连续性)The law of mass continuity (质量连续性) states that for incompressible (不可压缩的) liquid and in a system with impermeable (不可渗透的) wall, the rate of flow is constant:2211v A v A Q == 10.4WhereQ: the rate of flow, A: the cross-sectional area of the liquid, and v: the average velocity of the liquid in that cross-sectional location. The description 1 and 2 refer to two different locations in the system. For example, for sprue design: 2121h h A A = 10.5 so, the area of the bottom in the sprue is smaller than that of top, that means tapered sprue (圆锥型铸道).Aspiration: 吸出, choke: 节流口，缩颈Recall that in a free-falling liquid ( such as water from a faucet: 水龙头) the cross-section area of the stream decreases as it gains velocity downward. If we design a sprue with a constant cross-section area and pour the molten metal into it, regions may develop where the liquid loss contact with the sprue walls. As a result aspiration, a process whereby air is sucked in or entrapped in the liquid, may take place. On the other hand, tapered sprues are now replaced in many systems by straight-sided sprures with a choke to allow the metal to flow smoothly.回想自由落下的水流 (例如从水龙头流下的水)，其横截面积随其获得的向下的速度而减小。

05金属锻造forging of Metals

impression 模膛
1) Forging impression
(1)finishing终锻模膛： (1)finishing终锻模膛：
•Obtain final shape.获得 shape.获得锻件的最终尺寸。 •All the transition should be smooth.所有转角 smooth.所有转角都为圆角。 •Surface perpendicular to parting line should have draft angle.垂直于分模面 angle.垂直于分模面的表面都有模锻斜度。 •Land and gutter shfter Forging
Figure 14.8 Trimming flash from a forged part. Note that the thin material at the center is removed by punching.
ClosedClosed-Die Forging Versus Flashless Forging
4、mechanical press 曲柄压力机上模锻
• Drive system曲柄压力 system曲柄压力机的传动系统：机的传动系统： • characteristics特点： characteristics特点： • Stroke is fixed.滑块行 fixed.滑块行程固定 • Die insert can be used. 采用组合模 • With guide and ejector pin.有导向、顶杆装置 pin.有导向、顶杆装置 • Suitable of large
3.Screw presses摩擦压力机上模锻 presses摩擦压力机上模锻

制造工程与技术(热加工)英文版joining processes and equipment(3)

• the metals joined, 焊接金属 Temperature distribution for welding of different materials under same energy input and same welding speed.
• the welding process, 焊接方法
The heat applied during welding recrystallizes (再结晶）the 再结晶）再结晶 elongated grains of the cold-worked （冷轧拉长的晶粒）base metal. 冷轧拉长的晶粒） ① Grains that are away from the weld metal will recrystallize into fine equiaxed grains（等轴晶）. 等轴晶） ② Grains close to the weld metal, on the other hand, have been subjected to elevated temperatures for a longer period of time，， consequently they will grow. This growth will cause their region to be softer and to have less strength. ③ For some materials under a certain welding processes, harden region will appear after cooling. Quenching 淬火
Figure 29.4 Schematic illustration of various regions in a fusion weld zone (and the corresponding phase diagram) for 0.30% carbon steel

机械制造技术英文PPT14

Chip Tool
Workpiece
Fig.1 Generation and transmission of cutting heat
When cutting ductile materials, the deformation and friction are greater, so more heat is generated. When its cutting speed is increased, because the deformation of chips are smaller, so the percentage of heat generated by plastic deformation is reduced, but the percentage of friction generated heat is much higher. When cutting brittle materials, the percentage of heat generated by friction on the flank surface increases.
④ The contact length of the cutter face is narrow, so the temperature rise and fall on the workpiece surface is completed in a very short time. When the tool passes, the machined surface is subjected to a thermal shock .
Chip Tool
① In the shear zone, the temperature of each point along the shear plane is almost the same, but the temperature gradient in the direction perpendicular to the shear plane is very large.

机械制造专业外文翻译--锻造

英文原文：A.1 FORGINGBulk defirnnation of metals refers to various processes, such as forging, rolling, or extruding, where there is a controlled plastic flow or working of metals into useful shapes. The most well known of these processes is forging where deformation is accomplished by means of pressure, impact blows, or a combination of both.Hammer ForgingHanuner forging consists of striking the hot metal with a large semiautomatic hammer. If no dies are involved, the forging will be dependent mainly on the skill of the operator. If closed or impression dies are used, one blow is struck for each of several (lie cavities. A- gain, productivity and quality depend to a large degree on the skill of the hanimer operator and the tooling.Press ForgingPress forging is characterized by a slow squeezing action. Again, open or closed dies may be used. The open dies are used chiefly for large, simple-geometry parts that are later machined to shape. Closed-die forging relies less on operator skill awl more on the design of the preform and forging dies.2 As an example of the versatility of the process, newer developments have made it possible to produce bevel gears with straight or helical teeth. Rotation of the die (luring penetration will press bevel gears with spiral teeth.Open-die ForgingOpen-die forging is distinguished by the fact that the metal is never completely confined as it is shaped by various dies. Most open-die forgings are produced on flat, V, or swaging dies. Round swaging (lies and V dies are used in pairs or with a flat die. The top (lie is attached to the ram of the press, and the bottom die is attached to the hammer anvil or, in the case of press open-die forging, to the press bed.As the workpiece is hammered or pressed, it is repeatedly manipulated between the dies until hot working forces the metal to the final dimensions, as-shown in Fig. 1. After forging, the part is rough- and finished-machined. As an example of the amount of material allowed for machining, a 6.5 in. diameter shaft would have to be forged to 7.4 in. dianieter.In open-die forging of steel, a rule of thumb says that 50 lb of falling weight is required for each square inch of cross section.Impression-die ForgingIn the simplest example of impression-die forging, two dies are brought together, and the workpiece undergoes plastic deformation until its enlarged sides touch the side walls of the die (Fig. 2). A small amount of material is forced outside the die impression, forming flash that is gradually thinned. The flash cools rapidly and presents increased resistance to deformation, effectively becoming a part of the tool, and helps build up l)ressUre inside the bulk of the work- piece that aids material flow into unfilled impressions.Closed-die forgings, a special form of impression-die forging, does not depend on theformation of flash to achieve complete filling of the (lie. Thus closed-die forging is considerably more demanding on die design. Since pressing is often completed in one stroke, careful control of the workpieee volume is necessaiy to achieve complete filling without generating extreme pressures in the dies from overfilling.Extrusion ForgingAs with upsetting, extrusion forging is often accomplished by cold working. Three principal types of metal displacement by plastic flow are involved. Backward and forward, tube, and impact extrusion are shown in Fig. 3. The metal is placed in a container and corn- pressed by a ram movement until pressure inside the metal reaches flow-stress levels. The workpiece completely fills the container, and additional pressure causes it to leave through an orifice and form the extruded product.Extruded products may be either solid or hollow shapes. Tube extrusion is used to produce hollow shapes such as containers and pipes. Reverse-impact extrusion is used for mass production of aluminum cans. The ram hits a slug of metal in the die at high impact, usually 15 times the yield strength of the metal, which causes it to flow instantaneously up the walls of the die. Other common hollow extrusion products are aerosol cans, lipstick cases, flashlight cases, and vacuum bottles. Secondary operations, such as heading, thread rolling, dimpling, and machining, are often needed to complete the items.Generally steel impacts are limited to 2.5 times the punch diameter. Hydraulic presses areused for loads of over 2000 tons because they have a greater variation in stroke length, speed,and other economic advantages. Tolerances vary with materials arid design, hut productionruns calling for 0.002- to 0.005-in, tolerance are regularly made.Roll ForgingRoll forging in its simplest form consists of a heated billet passing between a pair of rollsthat deform it along its length (Fig. 8-4). Compared to conventional rolling processes, therolls are relatively small in diameter and serve as an arbor into which the forging tools aresecured. The active surface of the tool occupies only a portion (usually half) of the rollcircumference to accommodate the full cross section of the stock.The reduction of the cross section obtainable in one pass is limited by the tendency of thematerial to spread and form an undesirable flash that may be forged into the surface as a90rota- defect in the subsequent operations. The workpiece is int roduced repeatedly withtion between passes.Ring RollingRing rolling offers a homogeneous circumferential grain flow, ease of fabrication andmachining, and versatility of material size . Manu- facture of a rolled ring starts with asheared blank, which is forged to a pancake, punched, and pierced.There is no limit to the size of the rolled rings, ranging from roller-bearing sleeves to Fig.4 Roll forging rings 25 ft in diameter with face heights of 80 in. Various profiles may berolled by suitably shaping the driven, idling rolls.CAD/CAM in ForgingCAD/CAM is being increasingly applied to frging. Using the three-dimensional description of a machined part, which may have been computer designed, it is possible to generate the geometry of the associated forging. Thus the forging sections can be obtained from a common (laiR base. Using well-known techniques, forging loads and stresses can be obtained and flash dimensions can be selected for each section where metal flow is approximated as ro dimensional (plane strain or axisymmetric ). In some relatively simple section geomethes, computer simulation can be conducted to evaluate initial guesses on preform sections. Once the preform geometry has been developed to the designer¡¯s satisfaction, this geometric data base can utilized to write NC part programs to obtain the NC tapes or disks for machining.A.2 HEAT TREATMENT OF METALAnnealingThe word anneal has been used before to describe heat-treating processes for softening and regaining ductility in connection with cold working of material. It has a similar meaning when used in connection with the heat treating of allotropic materials. The purpose of full annealing is to decrease hardness, increase ductility, and sometimes improve machinability of high carbon steels that might otherwise be difflcult to cut. The treatment is also used to relieve stresses, refine grain size, and promote uniformity of structure throughout the material.Machinability is not always improved by annealing. The word machinability is used to describe several interrelated factors, including the ability of a material to be cut with a good surface finish. Plain low carbon steels, when fully annealed, are soft and relatively weak, offering little resistance to cutting, but usually having sufficient ductility and toughness that a cut chip tends to puli and tear the surface from which it is removed, leaving a comparatively poor quality surface, which results in a poor machinability rating. For such steels annealing may not be the most suitable treatment. The machinability of many of the higher plain carbon and most of the alloy steels can usually be greatly improved by annealing, as they are often too hard and strong to be easily cut at any but their softest condition .The procedure for annealing hypoeutectoid steel is to heat slowly to approximately 60C︒above the Ac3 line, to soak for a long enough period that the temperature equalizes throughout the material and homogeneous austenite is formed, and then to allow the steel to cool very slowly by cooling it in the furnace or burying it in lime or some other insulating material. The slow cooling is essential to the precipitation of the maximum ferrite and the coarsest pearlite to place the steel in its softest, most ductile, and least strained condition. NormalizingThe purpose of normalizing is somewhat similar to that of annealing with the exceptions that the steel is not reduced to its softest condition and the pearlite is left rather fine instead of coarse. Refinement of grain size, relief of internal stresses, and improvement of structural uniformity together with recovery of some ductility provide high toughness qualities in normalized steel. The process is frequently used for improvement of machinability and for stress nlief to reduce distortion that might occur with partial machining or aging.The procedure for normalizing is to austenitize by slowly heating to approximately80above the Ac3 or Accm3 temperature for hypoeutectoid or hypereuteetoid steels, C︒respectively; providing soaking time for the formation of austenite; and cooling slowly in still air. Note that the steels with more carbon than the eutectoid composition are heated above the Aom instead of the Ac used for annealing. The purpose of normalizing is to attempt to dissolve all the cementite during austenitization to eliminate, as far as possible, the settling of hani, brittle iron carbide in the grain boundaries. The desired decomposition products are smallgrained, fine pearlite with a minimum of free ferrite and free cementite. SpheroidizingMinimum hardness and maximum ductility of steel can he produced by a process called spheroidizing, which causes the iron carbide to form in small spheres or nodules in a ferrite matrix, in order to start with small grains that spheroid ize more readily, the process is usually performed on normalized steel. Several variations of processing am used, but all reqllin the holding of the steel near the A1 temperature (usually slightly below) for a number of hours to allow the iron carbide to form on its more stable and lower energy state of small, rounded glohules.The main need for the process is to improve the machinability quality of high carbonsteel and to pretreat hardened steel to help produce greater structural uniformity after quenching. Because of the lengthy treatment time and therefore rather high cost, spheroidizing is not performed nearly as much as annealing or normalizing.Hardening of SteelMost of the heat treatment hardening processes for steel are basel on the production of high pereentages of martensite. The first step. therefore, is that used for most of the other heat-treating processes-treatment to produce austenite. Hypoeutectoid steels are heated to approximately 60CC above the Ac3 temperature and allowed to soak to obtain temperature unifonnity and austenite homogeneity. Hypereutectoid steels are soaked at about 60CC above the A1 temperature, which leaves some iron carbide present in the material.The second step involves cooling rapidly in an attempt to avoid pearlite transformation by missing the nose of the i-T curve. The cooling rate is determined by the temperature and the ability of the quenching media to carry heat away from the surface of the material being quenched and by the conduction of heat through the material itself. Table1 shows some of the commonly used media and the method of application to remove heat, arranged in order of decreasing cooling ability.High temperature gradients contribute to high stresses that cause distortion and cracklug, so the quench should only as extreme as is necessary to produce the desired structure. Care must be exercised in quenching that heat is removed uniformly to minimize thermal stresses.For example, a long slender bar should be end-quenched, that is, inserted into the quenching medium vertically so that the entire section is subjected to temperature change at one time. if a shape of this kind were to be quenched in a way that caused one side to drop in temperature before the other, change of dimensions would likely cause high stresses producing plastic flow and permanent distortion.Several special types of quench are conducted to minimize quenching stresses and decrease the tendency for distortion and cracking. One of these is called martempering and consists of quenching an austenitized steel in a salt at a temperature above that needed for the start of martensite formation (Ms). The steel being quenched is held in this bath until it is of uniform temperature but is removed before there is time for fonnation of bainite to start. Completion of the cooling in air then causes the same hard martensite that would have formed with quenching from the high temperature, but the high thermal or ¡°quench¡± stresses that are the primary source of cracks and warping will have been eliminated.A similar process performed at a slightly higher temperature is called austempering. In this case the steel is held at the bath temperarnre for a longer period, and the result of the isothermal treatment is the formation of bainite. The bainite structure is not as hard as the martensite that could be formed from the same composition, but in addition to reducing the thermal shock to which the steel would be subjected under normal hardening procedures, ii is unnecessary to perform any further treatment to develop good impact resistance in the high hardness rangeTemperingA third step usually required to condition a hardened steel for service is tempering, or as it is sometimes referred to, drawing. With the exception of austempered steel, which is frequently used in the as-hardened condition, most steels are not serviceable “as quenched”. The drastic cooling to produce martensite causes the steel to be very hard and to contain both macroscopic and microscopic internal stresses with the result that the material has little ductility and extreme brittleness. Reduction of these faults is accomplished by reheating the steel to some point below the A1 (lower transformation) temperature. The stnictural changes caused by tempering of hardened steel are functions of both time and temperature, with temperature being the most important. It should be emphasized that tempering is not ahardening process, but is, instead, the reverse. A tempered steel is one that has been hardened by heat treatment and then stress relieved, softened, and provided with increased ductility by reheating in the tempering or drawing procedure.The magnitude of the structural changes and the change of properties caused by tempering depend upon the temperature to which the steel is reheated. The higher the ternperatun, the greater the effect, so the choice of temperature will generally depend on willingness to sacrifice hardness and strength to gain ductility and toughness. Reheating to below lOOt has little noticeable effect on hardened plain carbon steel. Between lO(YC and 200T, there is evidence of some structural changes. Above 200T marked changes in structure and properties appear. Prolonged heating at just under the A1 temperature will result in a spheroidized structure similar to that produced by the spheroidizing process.In commercial tempering the temperature range of 25O-425 is usually avoided because of an unexplained embrittlement, or loss of ductility, that often occun with steels ternpered in this range. Certain alloy steels also develop a ¡°temper brittleness¡± in the tempera- ture range of 425-600C︒, particularly when cooled slowly from or through this range of temperature. When high temperature tempering is necessary for these steels, they are usually heated to above 600C︒and quenched for rapid cooling. Quenches from this temperature, of course, do not cause hardening because austenitization has not been accomplished.中文译文：B.1 锻造金属变形方法有多种，比如通过锻造、滚压或挤压，使金属的塑性流动或加工受到控制而得到有用的形状。

制造工程与技术(热加工)英文版joining_processes_and_e

吴林教授：
1. 制造技术的三个基本功能：成形、连接、改性； 2. 古代焊接起源于中国，现代焊接发展于西方； 3. 焊接已经逐渐从技术走向科学。
三种焊接原理还没有形成一个统一的科学理论；宏观、细观、界观、微观；还有若干自然现象：太空环境下材料的粘连，冰和肌肉的粘连等；各种新材料的连接，特别是陶瓷、高温材料、碳纤维、复合材料、
Brazing and soldering Solid state
Chemical Electrical
Electrical Chemical Mechanical
Oxyfuel gas Thermit
1. Oxyfuel Gas Welding（氧燃气焊接，气焊）: A general term used to describe any welding process that uses a fuel gas combined with oxygen to produce a flame, which is the source of the heat that is used to melt the metals at the joint.
Shielded Metal-Arc
Submerged Arc
Gas Metal-Arc
Flux-Cored Arc
Gas Tungsten-Arc
Plasma Arc
Electron-Beam
Laser-Beam
Electro-gas Electro-slag Atomic Hydrogen et al
The application The joint design The materials involved The shapes of the components to be joined, their thicknesses, and their sizes Others: the location of the joint within the product, component numbers, the operator skill required, costs and so on.

制造工程与技术(热加工)双语15 Extrusion and Drawing of Metals

Chapter 15 Extrusion and Drawing of Metals（金属的挤压与拉拔）•15.1 Introduction•15.2 The Extrusion Process•15.3 Extrusion Practice•15.4 Hot Extrusion•15.5 Cold Extrusion•15.6 Impact Extrusion•15.7 Hydrostatic Extrusion•15.8 Extrusion Defects•15.9 Extrusion Equipment•15.10 The Drawing Process•15.11 Drawing Practice•15.12 Defects and Residual Stresses•15.13 Drawing Equipment15.1 Introduction1.Extrusion—It is a process where a billet is forcedthrough a die.–extruded parts have constant cross-section（截面恒定/等截面）–may be carried out at room or elevated temperature.–is a batch or semicontinuous process（分批或半连续生产）凹模/模口推杆Figure 15.1 Schematic illustration of the direct extrusion process.Extrusions （挤出件）Figure 15.2 Extrusions, and examples of products made by sectioning off extrusions. Source : Kaiser Aluminum.•solid （实心的）or hollow （中空的）cross-section•essentially semifinishedparts （半成品）•can be cut into desired lengths coat hanger gearbracket （支架）Typical Extruded ProductsØrailings（滑轨）for sliding doorsØtubing（管件）having various cross-section Østructural and architectural shapes（结构或建筑型材）Ødoor and window frames（门框及窗框）Typical Extruded ProductsExtruded profiles （型材）with various cross-sectionExtruded Materials•Common used Material–aluminum–copper（Cu）–steel–magnesium（Mg）–lead（Pb）•Other metals and alloys–with various levels of difficulty •Plastics2.Drawing –It is a process where a cross-section of solidrod（杆材）, wire（线材）, or tubing（管材）isreduced or changed in shape by pulling it through a die.–drawn parts also have constant cross-section冷拔–usually be carried out at room temperature.–may be a continuous process（连续生产）ArrayFigure 15.18 Process variables in wire drawingTypical Drawn Products•rods （棒材）–used for shafts, spindles（芯轴）, and small pistons（活塞）–as raw material for fasteners such as rivets, bolts, and screws •various profiles（型材）•wire（线材）–smaller in cross-section than rod, down to 0.01 mm in diameter, or even smaller–in industry, wire is generally defined as a rod that has beendrawn through a die at least once–cover a wide range of applications, such as electrical andelectronic wiring cables（电线/电缆）, tension-loaded（受拉载荷）structural members, welding electrodes（焊条）,springs, paper clips, spokes（轮辐）for bicycle wheels, andstringed musical instruments（弦乐器）.rod and wire (stainless steel)Drawing Applications绞线/合股15.2 The Extrusion Process1.Direct Extrusion（正挤）– a round billet is placed in a chamber (container) and forced through a die opening by a hydraulically-driven ram（液压驱动的柱塞） or pressing stem – also called forward extrusion模膛衬套毛坯凹模/模口推杆凹模支座挤压垫挤出件模膛/容器pressing stembillet dieThe metal flows in the same way that the pressing stem moves.空心杆正向挤压实心杆正向挤压Characteristics of Direct Extrusion特点: 1、挤压过程中挤压筒与金属坯料间的摩擦力大，消耗能量多；缺点2、金属变形不均匀； 3、压余（挤压余料）多，可达10-15%； 4、更换模具简单、迅速，所需辅助时间少；优点5、制品表面质量好。

制造工程及技术(热加工)10章

• Mold Geometry • Skin thickness
Heat Transfer
• Shrinkage – causes dimensional changes and, sometimes cracking, is the result of the following: – Contraction prior to solidification – Contraction during phase changes – Contraction as temperature drops to ambient temperature
Pure Metals
• Have a clearly defined melting point • Temperature remains constant during freezing • Solidifies from the walls of the mold toward the center of the part
Introduction
Important Considerations
– Flow of Molten Metal – Solidification and Cooling – Type of Mold Material
Solidification of Metals
Involves liquid metal turning back in to solid metal The process is different for Pure metals and alloys Can be divided into two steps: Formation of stable nuclei Growth of crystals

材料成型及控制工程外文翻译--金属热处理

外文原文：Metal heat treatmentMetal heat treatment is a kind of craft to heat pieces of metals at the suitable temperature in some medium and to cool them at different speed after some time.The metal heat treatment is one of the important crafts in the machine-building, comparing with other technologies, the heat treatment seldom changes the form of the work pieces and chemical composition of the whole .it improve the serviceability of the work piece through changing their micro- work pieces, chemical composition, or surface. Its characteristic is improving inherent quality of work pieces which can not be watched by our eyes.In order to make the metal work piece have mechanics , physics and chemical property which are needed, besides the use of many materials and various kinds of crafts which are shaped , the heat treatment craft is essential. Steel is a wide-used material in the mechanical industry, its complicated micro-composition can be controlled through the heat treatment , so the heat treatment of the steel is a main content of the metal heat treatment . In addition aluminium, copper, magnesium, titanium and their alloys also can change their mechanics , physics and chemical property through the heat treatment to make different serviceability.During the process of development from the Stone Age to the Bronze Age and to the Iron Age, the function of the heat treatment is gradually known by people. As early as 770 B.C.~222 B.C., the Chinese in production practices had already found the performance of the copper and iron changed by press and temperature . White mouthfuls of casting iron’s gentle-treatment is a important craft to make farm implements.In the sixth century B.C., the steel weapon was gradually adopted. In order to improve the hardness of the steel, quench craft was then developed rapidly. Two sword and one halberd found in YANXIA, Hebei of China , had “MA structure” in its micro-composition which was quenched.With the development of quenching technology, people gradually found the influence of cold pharmaceutical on quality of quenching. Pu yuan a people of theThree Kingdoms(now, Shanxi province Xiegu town)made3000 knives for Zhu Ge-liang.the knives were quenched in Chengdu according to legend. This proved that the chinese had noticed the cooling ability of waters with different quality in ancient times, and the cooling ability of the oil and urine at the same time were found. People found a sword in Zhongshan tomb which were up to the Western Han Dynasty (B.C. 206 -A.D. 24 ),in whose heart department carbon was about 0.15-0.4%, but on whose surface carbon was about more than 0.6%.this has shown the use of the carburization craft. But as the secret of individual's " craftsmanship " at that time, the development was very slow.In 1863, Britain metallo graphy expert and geologist's discoverity that six kinds of different metallography organizations existed in the steel under the microscope, proved that the inside of steel would change while heating and cooling. the looks of steel at the high temperature would change into a harder looks when urgently colded. Frenchmen Osmon established Allotropic theory , and Englishmen Austin first made the iron- carbon looks picture .these tow theories set the theoretical foundation for the modern heat treatment craft . Meanwhile, people also studied the metal protection in the heating to avoid the metal's oxidizing and out of carbon in the course.1850~1880s, there were a series of patent to use kinds of gases to heat (such as hydrogen , coal gas , carbon monoxide etc. ). Englishman's Rec obtained the patent of bright heat treatment of many kinds of metal in 1889-1890.Since the 20th century, the development of metal physics and transplantation application of other new technologies,make the metal heat treatment craft develop on a large scale even more. A remarkable progress was carburizition of gas in a tube of stoves in industrial production during 1901~1925; 1930s the appeariance of the electric potential different count and then the use of carbon dioxide and oxygen made stove carbon of atmosphere under control . In 1960s, hot treatment technology used the function of the plasma field, developed the nitrogen, carburization craft.The application of laser , electron beam technology, made the metal obtain new method about surface heat treatment and chemical heat treatment.The metal heat treatment craftThe heat treatment craft generally includes heating, keeping and cooling andsometimes only heating and cooling two progresses . The course links up each other.Heating is one of the important processes of the heat treatment . There are a lot of heating methods of the metal heat treatment . the first heat source were the charcoal and coal , then liquid and gaseous fuel. The application of the electricity is easy to control the heating, and no environmental pollution. the heat source could be heated directly or indirectly by the use of salt or metal of melting or the floating particle.While metal heated, the work piece in air , is often oxidized or take off carbon ( steel's surface carbon content reduces).this does harm to the metal's surface performanc which is heated. Therefore metal should heat in the the vacuum or the melted salt, in controlled atmosphere or protected atmosphere . Sometimes it is heated in the protect means of coating or pack .Heating temperature is one of the important craft parameters of the heat treatment craft , choosing and controling heating temperature is a main matter of guaranting heat treatment quality. Heating temperature may change according to the different purposes of the heat treatment and different metal materials , but usually it is up to the temperature at which high temperature frame could be abtained.it must keep some time at the high temperature to make the inside and outside of the metal reach the some heating level,so that its micro-frame would turn out wholely.we call this period of time "keep-heat"time. There is no "keep-heat"time when adopting density heating and surface heat treatment of high energy because of the rapidity. But the chemical heat treatment often need much more time to sustain the heat .Cooling is an indispensable step in the craft course of heat treatment too . cooling methods are different because of crafts , mainly at controling the speed of cooling. generally anneals is slowest in speed, the cooling normalizing is a little fast in speed, the quenched cooling is much faster in speed. But there are different demands according to the kindof steel, for example empty hard steel can be cooled with normalize as quick as the speed by hard quench .The metal heat treatment craft can be divided into whole heat treatment , surface heat treatment and chemical heat treatment.Every kind could be divided into different crafts according to heating medium , heating temperature and cooling method. The same kind of metal adopting different heat treatment crafts can getdifferent organizations which have different performance . The steel is the widest-used metal on the industry, and its micro- organization is the most complicated, so the steel heat treatment craft is various in style.The whole heat treatment is to change the whole mechanics performance of work piece through heating the work piece wholely and then cooling at the proper speed. The whole heat treatment of steel roughly has four basic crafts of annealing , normalizing , quenching and flashing back .Annealing means heating the work piece to the proper temperature ,then adopting different temperature retention time according to the material and size of work piece and then cooling slowly, whose purpose is to make the metal organization to achieve or close to the balance state, obtain good craft performance and serviceability, or prepare for quench further. normalizing is to cool in the air after heating the work piece at suitable temperature , its result is similar to annealing except that the organization out of normalizing are more refined which is often used to inhance the cutting performance of the material and is occationally used for the final heat treatment of material which are not high-requested. .Quenching is to cool work piece which has been heated and kept in warm fast in the cold medium as water , oil , other inorganic salts ,or organic aqueous solution and so on . The steel quenched becomes hard and fragile too. To reduce its fragility , we must first keep the quenched piece of steel in a certain temperature which is higher than room temperature but lower than 650℃for a long time,and then cool it again. this progress is called the flashing back . Annealing , normalizing, quenching , flashing back is " four fires " in the whole heat treatment . the quenching contact close to flashing back ,and they are often used together." Four fire "is divided into kinds of heat treatment crafts by different heating temperatures and diferent ways of cooling. What is " quality adjust " is a kind of craft combining "quench" with "high-temper a ture flash back" to make the work piece obtain certain intensity and toughness. Some alloy saturation out of quench can improve its hardness, intensity, electricity and magnetism after it is kept in the high proper temperature for a little long time . Such heat treatment craft is called “effective dealing”.Deformation-heat-treatment is the combination of pressure-deformation and heat treatment on work piece ,this mothod could enhance its intensity; and vacuum-heat-treatment is that work piece is heated in atmosphere or vacuum.It can make the work piece not oxidize or take off carbons , keep its surface bright and neat and improve its performance. At the same time ,it can carry on the chemical heat treatment by the pharmaceutics.Surface heat treatment on work piece is only to heat its cover to change the metal-layer's mechanics performance. In order to only heat the layer of work piece without making too much heat spreading into the inside, the heat source used must be of high density of energy , namely it can offer greater heat energy on the unit's area of the work piece and make its layer or parts reach high temperature in short-term or instantaneously. The main method of the surface heat treatment is "flame quenching" and "reaction heat" treatment and the heat source used commonly are flame as oxygen acetylene or propane, reaction electric current, laser and electron beam,ect.The chemical heat treatment is to alter the chemical composition, organization and performance of the top layer of work piece.The difference between Chemical and surface heat treatment is that the latter just change the chemical composition of the top layer of work piece . The former is to set the work piece heating in the medium (the gas , liquid , solid ) including carbon , nitrogen or other alloying elements,and then to keep it warm for longer time, thus to make elements as the carbon,nitrogen,boron and chromium,etc permeate through the top layer of work piece.Sometimes after permeation, there is other heat treatment craft to carry on such as quenching and flashing back . The main method of the chemical heat treatment include carbon,nitrogen, and metal permeation.The heat treatment is one of the important processes in machine components and tool and mould manufacture. Generally speaking, it guarantees and improves various kinds of performance of the work piece , for instance wear proof and anti-corrosion. It also improve the organization and state of the tough work piece to ensure various kinds of cooling and heating work.For example tin are annealed for a long time to turn into malleable cast iron which is of plasticity. proper heat treatment craft can prolong the gear wheel's servicelife at double or dozens of times than these without heat treatment ; In addition, the cheap carbon steel with some alloying elements permeated will own the alloy steel performance whose prices hold high so that it can replace some heat-resisting steel , stainless steel ; all tool and mould need to be through the heat treatment before in use..中文译文：金属热处理金属热处理是将金属工件放在一定的介质中加热到适宜的温度，并在此温度中保持一定时间后，又以不同速度冷却的一种工艺。

制造技术专业英语翻译

7.1 NA TURE OF PLASTIC DEFORMATIONPlastic deformation is the deformation which is permanent and beyond the elastic rang of the material of ten , metals are worked by pfastic deformation because of the beneficial effect that is imparted to the mechanical properties by it. The necessary deformation in a metal can be achieved by application of large amount of mechanical force only or by heating the metal and then applying a small force.7.1 塑性变形本质塑性变形是超过弹性变形范围之后的一种永久变形。

通常，金属采用塑性变形加工是因为可以通过其获得良好的机械性能。

金属所需要的变形可以只通过施加大量的机械力或者通过加热金属并且施加少量的应力来获得。

The deformation of metals, which is caused by the displacement of the atoms is achieved by one or both of the processes called slip and twinning. The details of the microscopic deformation methods can be found in the textbooks of' metallurgy. On the macroscopic scale, when plastic , deformation occurs the metal appears to flow in the solid state along specific directions, which are depedent on the type of processing and the direction of applied force. The crystals or grains of the metal are elongated in the direction of metal flow. This flow of metal can be seen under microscope after polishing and suitable etching of the mental surface . These visible lines are called fibre flow lines, some representative specimens of which are presented in fig金属的变形是由原子排列引起的，这种排列是由被称作滑移和孪生过程中的一种或者两者共同作用造成的。

制造工程与技术(热加工)英文版joining_processes_and_e

The purpose of the flux: ① to remove oxides from the surfaces ② to generate gaseous and slag shield ③ to take part in the metallurgical reactions
异种材料等的连接问题有待于实现和发展。
——焊接的问题基本上是一个材料界面的科学问题
手艺
技术
科学
§27 Fusion-Welding Processes 熔焊
welding
Fusion
Brazing and soldering Solid state
Chemical Electrical
Electrical Chemical Mechanical
吴林教授：
1. 制造技术的三个基本功能：成形、连接、改性； 2. 古代焊接起源于中国，现代焊接发展于西方； 3. 焊接已经逐渐从技术走向科学。
三种焊接原理还没有形成一个统一的科学理论；宏观、细观、界观、微观；还有若干自然现象：太空环境下材料的粘连，冰和肌肉的粘连等；各种新材料的连接，特别是陶瓷、高温材料、碳纤维、复合材料、
Give some examples of Joining Processes you known.
Why joining processes?
Without joining, there would not be modern industry. Because products or parts would be Impossible to manufacture Expensive Difficult to maintenance Hard to get different properties Difficult to transportation

制造技术第1卷铸造成形和焊接英文版.原书第三版教学设计

制造技术第1卷铸造成形和焊接英文版.原书第三版教学设计AbstractIn this teaching design, students will learn about casting and welding as part of the manufacturing process. The course will be based on the third edition of the English version of Manufacturing Technology Volume 1: Casting and Welding. Students will gn knowledge about different casting processes, their benefits and applications, as well as the key aspects of welding. They will also learn about the tools, equipment, and safety measures required for these processes.IntroductionAs an important part of manufacturing, casting and welding have been widely used in various fields. Casting is the process of forming metal objects by pouring molten metal into a mold, while welding is the process of joining two materials by heating and melting them to form a strong bond. Understanding these two processes is crucial for students pursuing a career in manufacturing. This teaching design is intended to provide students with a solid understanding of casting and welding principles.Teaching Objectives•To introduce the basic principles of casting and welding in manufacturing•To describe and compare different casting processes, their benefits and applications•To expln the key aspects of welding, including equipment, tools, and safety measures•To encourage students to interact with case studies, problems and discussions related to casting and welding Course OverviewThis course will be based on the third edition of the English version of Manufacturing Technology Volume 1: Casting and Welding. The course will cover a range of topics, including:•Introduction to casting and welding inmanufacturing•Sand casting process•Investment casting process•Die casting process•Centrifugal casting process•Welding processes•Safety measures for casting and weldingIn addition, to ensure students have grasped the contentof each chapter, homework will be assigned.Chapter 1 - Introduction to Casting and Welding in ManufacturingChapter 1 will introduce the basic principles of casting and welding in the manufacturing industry. This will include a brief history of casting and welding, its importance, and its role in modern-day Manufacturing. The castability of metals, factors influencing castability, as well as welding challenges will also be explored in this chapter.Chapter 2 - Sand CastingChapter 2 will cover the most common casting process used in industry – sand casting. This chapter will describe the process of making a sand mold, melting the metal, and pouring it into the mold. The different types of sand used in sand casting, as well as core-making techniques, will also be discussed. The advantages and limitations of sand castingwill also be explored in detl.Chapter 3 - Investment CastingChapter 3 will cover the investment casting process – a highly precise casting process that is widely used in the production of parts for the aerospace and medical industries.This chapter will describe the process of making a ceramic mold, melting the metal, and pouring it into the mold. The advantages and limitations of investment casting will be compared to sand casting.Chapter 4 - Die CastingChapter 4 will cover die casting - an efficient and highly automated casting process used for mass production of small and medium-sized parts. This chapter will describe the process of using a die to inject molten metal into a mold, and the different types of dies used in die casting. The advantages and limitations of die casting will also be explored.Chapter 5 - Centrifugal CastingChapter 5 will introduce centrifugal casting, which involves pouring molten metal into a rapidly rotating mold. This process results in a high-quality casting with a fine-grned surface finish. This chapter will explore the different types of molds used in centrifugal casting, as well as the advantages and limitations of this process.Chapter 6 - Welding ProcessesChapter 6 will discuss the principles and types of welding processes. The chapter will cover the mn welding processes,including arc welding, gas welding, and resistance welding. The advantages and limitations of each welding process will also be explored. Safety measures for welding will also be emphasized.Chapter 7 - Safety Measures for Casting and WeldingChapter 7 will emphasize the importance of safety measures for casting and welding. Students will learn about the tools and equipment used in casting and welding, including personal protective equipment and safety devices. This chapter will also cover the safety measures related to different types of casting and welding processes, including handling of molten metal and gases.ConclusionIn conclusion, this teaching design ms to provide students with a solid understanding of casting and welding principles, different casting processes, their benefits and applications, the key aspects of welding, as well as the tools, equipment, and safety measures required for these processes. By completing this course, students will be able to apply their knowledge of casting and welding to a variety of Engineering applications.。

制造工程与技术(热加工)(英文版)免费

宁波大学工学院
Manufacturing Engineering
Casting
1.2 Casting process
Casting process:
(a)
Pouring molten metal into a mold patterned after the part to be manufactured;
Casting
1.1 Concept of casting
Trends:

Mechanization and automation of the casting process Increasing demand for high-quality castings with close dimensional tolerances and no defects
Two groups of casting activities: 1. Pattern and mold making---- CAD, CAM, RPM 2. Melting the metals, pouring molten metal into mold ----automated machinery, industry robot
宁波大学工学院
Manufacturing Engineering
Casting
1.5 Sand casting
Cores: For casting with internal cavities or passages, cores are used. Core are placed in the mold cavity before casting to form the interior surfaces of the casting and removal from the finished part during shakeout and further processing.