金属材料的切削加工毕业论文外文翻译.doc

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1、附录1： 化制造设备，极大地提高材料切除率，并保证加工精度和加工质量的现代制造技术。具有以下特征：切削力低、热变形小、材料切除率高、高精度、减少工序。高速切削技术的出现，使得硬质合金模具的应用范围日益扩大，可目前高速切削技术的切削机理还没有成型的理论，高速切削机床没有得到大规模的应用，现在购买一台高速切削机床需要100400万元人民币，一般的小型模具制作企业的资金不够购买这样昂贵的高速切削机床。重切削加工是用切削工具，把坯料或工件上多余的材料层切去，使工件获得规定的几何外形、尺寸和表面质量的加工方法。任何切削加工都必须具备三个基本条件：切削工具、工件和切削运动。切削工具应有刃口，其材质必须比工

2、件坚硬；不同的刀具结构和切削运动形式，构成不同的切削方法。用刃形和刃数都固定的刀具进行切削的方法有车削、钻削、镗削、铣削、刨削、拉削和锯切等；用刃形和刃数都不固定的磨具或磨料进行切削的方法有磨削、研磨、珩磨和抛光等。切削加工是机械制造中最主要的加工方法。虽然毛坯制造精度不断提高，精铸、精锻、挤压、粉末冶金等加工工艺应用日广，但由于切削加工的适应范围广，且能达到很高的精度和很低的表面粗糙度，在机械制造工艺中仍占有重要地位。切削加工的历史可追溯到原始人创造石劈、骨钻等劳动工具的旧石器时期。在中国，早在商代中期（公元前13世纪），就已能用研磨的方法加工铜镜；商代晚期（公元前12世纪），曾用青铜钻头在

3、卜骨上钻孔；西汉时期（公元前206公元23），就已使用杆钻和管钻，用加砂研磨的方法在“金缕玉衣”的4000多块坚硬的玉片上，钻了18000多个直径12毫米的孔。17世纪中叶，中国开始利用畜力代替人力驱动刀具进行切削加工。如公元1668年，曾在畜力驱动的装置上，用多齿刀具铣削天文仪上直径达2丈（古丈）的大铜环，然后再用磨石进行精加工。18世纪后半期，英国工业革命开始后，由于蒸汽机和近代机床的发明，切削加工开始用蒸汽机作为动力；到19世纪70年代，切削加工中又开始使用电力。对金属切削原理的研究始于19世纪50年代，对磨削原理的研究始于19世纪80年代，此后各种新的刀具材料相继出现。19世纪末出现的

4、高速钢刀具，使刀具许用的切削速度比碳素工具钢和合金工具钢刀具提高两倍以上，达到25米/分左右；1923年出现的硬质合金刀具，使切削速度比高速钢刀具又提高两倍左右；30年代以后出现的金属陶瓷和超硬材料（人造金刚石和立方氮化硼），进一步提高了切削速度和加工精度。随着机床和刀具的不断发展，切削加工的精度、效率和自动化程度不断提高，应用范围也日益扩大，从而大大促进了现代机械制造业的发展。金属材料的切削加工有许多分类方法，常见的有按工艺特征、按材料切除率和加工精度、按表面成型方法三种分类方法。切削加工的工艺特征决定于切削工具的结构，以及切削工具与工件的相对运动形式。因此按工艺特征，切削加工一般可分为：车

5、削、铣削、钻削、镗削、铰削、刨削、插削、拉削、锯切、磨削、研磨、珩磨、超精加工、抛光、齿轮加工、蜗轮加工、螺纹加工、超精密加工、钳工和刮削等。按材料切除率和加工精度，切削加工可分为粗加工、半精加工、精加工、精整加工、修饰加工、超精密加工等。粗加工是用大的切削深度，经一次或少数几次走刀，从工件上切去大部分或全部加工余量的加工方法，如粗车、粗刨、粗铣、钻削和锯切等，粗加工效率高但精度较低，一般用作预先加工；半精加工一般作为粗加工与精加工之间的中间工序；精加工是用精细切削的方式，使加工表面达到较高的精度和表面质量，如精车、精刨、精铰、精磨等，精加工一般是最终加工。精整加工是在精加工后进行，其目的是为

6、了获得更小的表面粗糙度，并稍微提高精度。精整加工的加工余量小，如珩磨、研磨、超精磨削和超精加工等；修饰加工的目的是为了减小表面粗糙度，以提高防蚀、防尘性能和改善外观，而并不要求提高精度，如抛光、砂光等；超精密加工主要用于航天、激光、电子、核能等需要某些非凡精密零件的加工，其精度高达IT4以上，如镜面车削、镜面磨削、软磨粒机械化学抛光等。切削加工时，工件的已加工表面是依靠切削工具和工件作相对运动来获得的。按表面形成方法，切削加工可分为刀尖轨迹法、成形刀具法、展成法三类。刀尖轨迹法是依靠刀尖相对于工件表面的运动轨迹，来获得工件所要求的表面几何外形，如车削外圆、刨削平面、磨削外圆、用靠模车削成形面等

7、，刀尖的运动轨迹取决于机床所提供的切削工具与工件的相对运动；成形刀具法简称成形法，是用与工件的最终表面轮廓相匹配的成形刀具，或成形砂轮等加工出成形面，如成形车削、成形铣削和成形磨削等，由于成形刀具的制造比较困难，因此一般只用于加工短的成形面；展成法又称滚切法，是加工时切削工具与工件作相对展成运动，刀具和工件的瞬心线相互作纯滚动，两者之间保持确定的速比关系，所获得加工表面就是刀刃在这种运动中的包络面，齿轮加工中的滚齿、插齿、剃齿、珩齿和磨齿等均属展成法加工。有些切削加工兼有刀尖轨迹法和成形刀具法的特点，如螺纹车削。切削加工质量主要是指工件的加工精度和表面质量（包括表面粗糙度、残余应力和表面硬化）

8、。随着技术的进步，切削加工的质量不断提高。18世纪后期，切削加工精度以毫米计；20世纪初，切削加工的精度最高已达0.01毫米；至50年代，切削加工精度已达微米级；70年代，切削加工精度又提高到0.1微米。影响切削加工质量的主要因素有机床、刀具、夹具、工件毛坯、工艺方法和加工环境等方面。要提高切削加工质量，必须对上述各方面采取适当措施，如减小机床工作误差、正确选用切削工具、提高毛坯质量、合理安排工艺、改善环境条件等。提高切削用量以提高材料切除率，是提高切削加工效率的基本途径。常用的高效切削加工方法有高速切削、强力切削、等离子弧加热切削和振动切削等。磨削速度在45米秒以上的切削称为高速磨削。采用高

9、速切削（或磨削）既可提高效率，又可减小表面粗糙度。高速切削（或磨削）要求机床具有高转速、高刚度、大功率和抗振性好的工艺系统；要求刀具有合理的几何参数和方便的紧固方式，还需考虑安全可靠的断屑方法。强力切削指大进给或大切深的切削加工，一般用于车削和磨削。强力车削的主要特点是车刀除主切削刃外，还有一个平行于工件已加工表面的副切削刃同时参与切削，故可把进给量比一般车削提高几倍甚至十几倍。与高速切削比较，强力切削的切削温度较低，刀具寿命较长，切削效率较高；缺点是加工表面较粗糙。强力切削时，径向切削力很大故不适于加工细长工件。振动切削是沿刀具进给方向，附加低频或高频振动的切削加工，可以提高切削效率。低频振

10、动切削具有很好的断屑效果，可不用断屑装置，使刀刃强度增加，切削时的总功率消耗比带有断屑装置的普通切削降低40左右。高频振动切削也称超声波振动切削，有助于减小刀具与工件之间的摩擦，降低切削温度，减小刀具的粘着磨损，从而提高切削效率和加工表面质量，刀具寿命约可提高40%。对木材、塑料、橡胶、玻璃、大理石、花岗石等非金属材料的切削加工，虽与金属材料的切削类似，但所用刀具、设备和切削用量等各有特点。木材制品的切削加工主要在各种木工机床上进行，其方法主要有：锯切、刨切、车削、铣削、钻削和砂光等。塑料的刚度比金属差，易弯曲变形，尤其是热塑性塑料导热性差，易升温软化。故切削塑料时，宜用高速钢或硬质合金刀具，

11、选用小的进给量和高的切削速度，并用压缩空气冷却。若刀具锋利，角度合适，可产生带状切屑，易于带走热量。玻璃（包括锗、硅等半导体材料）的硬度高而脆性大。对玻璃的切削加工常用切割、钻孔、研磨和抛光等方法。对厚度在三毫米以下的玻璃板，最简单的切割方法是用金刚石或其他坚硬物质，在玻璃表面手工刻划，利用刻痕处的应力集中，即可用手折断。对大理石、花岗石和混凝土等坚硬材料的加工，主要用切割、车削、钻孔、刨削、研磨和抛光等方法。切割时可用圆锯片加磨料和水；外圆和端面可采用负前角的硬质合金车刀，以1030米分的切削速度车削；钻孔可用硬质合金钻头；大的石料平面可用硬质合金刨刀或滚切刨刀刨削；精密平滑的表面，可用三块

12、互为基准对研的方法，或磨削和抛光的方法获得。极速加工：能使实际使用的大直径工件以 4,000 rpm 的速度进行刚性攻牙刀具更换时间，T-T:1.6秒, C-C:3.2秒快移定位速度（X、Y轴）：48m/min（1889 IPM）快移定位速度（X、Y轴）：36m/min （1417 IPM）高性能主轴：4,000, 6,000, 8,000, 10,000 nd 12,000RPM主轴和Fanuc 控制器业界通用的标准40刀头其它优势：全部轴绝对编码，无转换限制全电动设计，非液压驱动可选择12或14把刀的刀具库极省空间的足踏设计人体工学设计使操作更舒适有效率CNC控制器：FANUC-21i-M

13、B快速进给率：48m/min（X,Y） 36m/min（Z）数据输入：以太网，RS232C，记忆卡电源：AC200/AC220V（11KVA）占地面积：16002360mm 行程：600400400mm附录2Manufacturing equipment, significantly higher material removal rate, and to ensure the machining accuracy and machining quality of modern manufacturing technology. Has the following characteristic

14、s: low cutting forces, heat distortion, material removal rate, high accuracy, reducing process. The emergence of high-speed cutting technology makes the application of carbide mold growing, high-speed cutting technology can present the cutting mechanism has not yet formed a theory, high-speed cuttin

15、g machines have not been large-scale application, is to buy a high-speed cutting machine needs 100 -400 million yuan, the average small mold making business is not enough money to buy such expensive high-speed cutting machines. Heavy cutting is to use cutting tools or workpieces on the blank layer c

16、ut away the excess material so obtained the required workpiece geometry, dimensions and surface quality of processing methods. Any cutting must meet three basic conditions: cutting tool, workpiece and cutting sports. Cutting tools should be edge, the material must be harder than the workpiece; diffe

17、rent forms of tool structure and cutting movement, constitute a different cutting method. Blade shape and edge with a fixed number of both methods of cutting tools for turning, drilling, boring, milling, planing, broaching, and sawing, etc.; edge shape and edge with no fixed number of abrasive or ab

18、rasive conduct cutting methods are grinding, grinding, honing and polishing. Cutting is the most important machine in the processing methods. Although the manufacture of precision rough rising casting, forging, extrusion, powder metallurgy processing applications on widely, but cutting a wide range

19、of adaptation, and can achieve high precision and low surface roughness, in Machinery manufacturing processes still occupy an important position. Cutting history dating back to primitive man to create stone splitting, bone drilling instruments of labor Paleolithic period. In China, as early as the m

20、id-Commerce (13th century BC), the method already grinding process can be used bronze mirrors; the late Shang Dynasty (12th century BC), have used bronze drill bit and drill a hole in Bogu; Western Han Dynasty ( 206 BC AD 23), already use the drill rods and drill pipe, method of grinding with sand i

21、n the jade dress and more than 4,000 pieces of jade tablet on a hard, drilling the more than 18,000 1 to 2 mm in diameter holes. Mid-17th century, China began to use animal power instead of human-driven tool for cutting. If the year 1668, he worked in animal-driven devices, with multiple tooth milli

22、ng cutter diameter astronomical apparatus 2 husbands (Guzhang) large copper ring, then use the grindstone for finishing. Half of the 18th century, the British industrial revolution began, as the invention of the steam engine and modern machine tools, cutting began to steam as the motive power; to th

23、e 19th century, 70s, began cutting the use of electricity. Principles of metal cutting began in the 19th century 50s, on the principle of grinding in the 19th century, 80 years since the new tool materials have appeared. 19 high speed steel cutting tool end of the century, so that the tools cutting

24、speed than the allowable carbon tool steel and alloy tool steel cutter for more than triple, to 25 m / min or so; carbide cutting tools appeared in 1923, compared to cutting speed high-speed steel cutting tools has raised about twice; 30 years after the emergence of metal-ceramic and superhard mater

25、ials (synthetic diamond and cubic boron nitride), to further improve the cutting speed and precision. With the continuous development of machine tools and cutting tools, precision cutting, efficiency and automation are continuously improving and expanding application range, thus greatly promoting th

26、e development of modern machinery manufacturing industry. Cutting of metal materials have many classifications have common characteristics by technology, by material removal rate and machining accuracy, surface forming method according to three types of classification. Features cutting process depen

27、ds on the structure of the cutting tool and cutting tool and workpiece relative motion form. So according to these processes, cutting general can be divided into: turning, milling, drilling, boring, reaming, planing, slotting, broaching, sawing, grinding, grinding, honing, super finishing, polishing

28、, Gear, Worm processing, thread processing, ultra-precision machining, bench and scrape so. By material removal rate and machining precision, machining can be divided into roughing, semi finishing, finishing, finishing processing, modification processing, ultra-precision processing. Roughing depth o

29、f cut is large, go through one or a few knife, cut away from the work most or all of the allowances of the processing methods, such as rough turning, rough planing, rough milling, drilling and sawing, etc. , roughing and high efficiency but low accuracy, normally used for pre-processing; semi-roughi

30、ng and finishing finishing generally as an intermediate between the processes; finishing with a fine cutting is a way to achieve high machining accuracy and surface surface quality, such as fine cars, fine planing, precision hinges, and fine grinding, finishing the final processing generally. Finish

31、ing after the process is finished, its purpose is to obtain a smaller surface roughness and slightly increased accuracy. Finishing of the machining allowance is small, such as honing, grinding, ultra fine grinding and super finishing, etc.; modification process is intended to reduce the surface roug

32、hness, to improve the corrosion, dust-proof performance and improve the appearance, but also does not require higher precision, such as polishing, sanding, etc.; ultra-precision machining is mainly used for aerospace, laser, electronics, nuclear energy needs of some of the extraordinary precision ma

33、chining, the precision of up to IT4 above, such as turning mirror, mirror grinding, Polishing chemical mechanical polishing grain. Cutting, the workpiece machined surface is to rely on cutting tools and workpieces for relative movement to obtain. By surface methods can be divided into cutting tip lo

34、cus, forming cutter method, generating method three. Tip trajectory method is to rely on tip relative to the trajectory surface, to obtain the required surface of the workpiece geometry, such as cylindrical turning, planing surface, cylindrical grinding, turning with a forming surface by mold and so

35、 on, tip trajectory depends on the machine tool cutting tools provided by the relative motion with the workpiece; Act referred to as forming method of forming tools, is the final workpiece surface profile that matches the shape tool, or forming a shaped surface grinding and other processing, such as

36、 the shape of turning, milling and shaping forming such as grinding, molding tool manufacturing as difficult it is generally only used for processing short shaped surface; Expansion method is also known as rotary cutting method, the processing time for cutting tool and workpiece relative develop int

37、o a movement, tool and workpiece instantaneous center line with each other for pure rolling, speed ratio established between the two relations, obtained by processing the surface is edge of this movement in the envelope, gear hobbing process in, shaper, shaving, honing, and grinding teeth, etc. are

38、generating method processing. Some of both cutting and forming tool tip trajectory method method characteristics, such as thread turning. Cutting quality mainly refers to the workpiece machining accuracy and surface quality (including surface roughness, residual stress and surface hardening). As tec

39、hnology advances, constantly improve the quality of cutting. The late 18th century, cutting precision in millimeters; the 20th century, reached the highest precision machining 0.01 mm; to 50 years, has reached micron machining accuracy; 70s, cutting accuracy has increased to 0.1 microns. Affect the

40、quality of the main factors cutting machine tools, tools, fixtures, workpiece blank, process methods and processing environment. To improve the cutting quality of these aspects must take appropriate measures, such as reduced machine tool error, the correct selection of cutting tools to improve the r

41、ough quality, reasonable arrangements for technology to improve environmental conditions. Cutting to improve the higher material removal rate is to improve the efficiency of the basic means of cutting. Commonly used methods of high speed machining cutting, heavy cutting, plasma arc cutting and vibra

42、tion cutting of heating. Grinding speed of 45 m / sec or as high-speed grinding cut. High-speed cutting (or grinding) can improve efficiency, but also reduce the surface roughness. High-speed cutting (or grinding) to require machines with high speed, high stiffness, high power and good anti-vibratio

43、n technology systems; required tool geometry parameters of reasonable and convenient fastening means need to consider the safe and reliable method of chip breaking . Feed cutting force means big or large depth of cut machining, generally used for turning and grinding. The main feature of turning pow

44、erful Tool addition to the main cutting edge, there is a parallel to the machined surface of the deputy involved in cutting edge while cutting, it can be to feed than the general turning several times and even 10 times increase. Compared with high-speed cutting, heavy cutting of the cutting temperat

45、ure is lower, longer tool life, cutting more efficient; drawback is that processing of the rough surface. Strong cutting, it is not suitable for processing large radial cutting forces slender workpiece. Vibration cutting tool along the feed direction, additional low-frequency or high frequency vibra

46、tion of the cutting process, can improve the cutting efficiency. Low frequency vibration cutting has a good chip breaking effects, do not chip breaking device so that the blade to increase strength, cutting the total power consumption than the chip-breaking device with ordinary cutting about 40% low

47、er. High-frequency vibration cutting, also known as ultrasonic vibration cutting, will help reduce friction between tool and workpiece, lower cutting temperature, reduce the adhesive wear tool to improve cutting efficiency and surface quality, tool life can be increased by 40% . Wood, plastic, rubbe

48、r, glass, marble, granite and other non-metallic materials, cutting, cutting and metal material although similar, but the use of tools, equipment and cutting parameters such as its own characteristics. Cutting wood products, mainly in a variety of woodworking machines on its main methods: sawing, pl

49、aning, turning, milling, drilling and sanding, etc. Worse than the stiffness of metal plastic, easy bending, especially thermoplastic poor thermal conductivity, easy to heat softening. Therefore, when cutting plastic, it is appropriate to high-speed steel or carbide cutting tools, use a small feed and high cutting speed