结 论
毕业设计是对每个即将毕业的大学生的一次考验和历练，通过这次毕业设计我把大学所学的大部分专业课程有了一个大体的贯穿。
毕业设计是我们学完了大学的全部课程以后进行的。这是我们对所学课程的一次深入的综合性的链接，也是一次理论联系实际的训练。因此，它在我们的大学学习生活中占有极其重要的地位。同时也是我们离校前的要交的最后的答卷。所以在这次设计中，在各位老师的悉心帮助下，我用心设计了我大学的最后一笔。
这次设计得到了很多老师和同学的大力帮助，在丰富自己专业知识的同时还增强了我加入团队完成任务的能力。在杨雪银老师的认真指导下，总共历时了三个多月的时间，包括中间搜集资料、确定生产类型、确定加工工艺过程等等，最后终于完成了这次毕业设计。通过这次设计使我对加工工艺有了更为深一步的了解，为走向工作岗位打下了基础。
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致 谢
紧张而又辛苦的三个月的毕业设计结束了。当我快要完成老师下达给我的任务的时候，我仿佛经过一次翻山越岭，登上了高山之颠，顿感心旷神怡，眼前豁然开朗。
毕业设计是我们专业课程知识应用的实践训练，这是迈向社会、走向工作岗位前的一个必不可少的过程。“千里之行始于足下”，通过这次课程设计，我深深体会到这句千古名言的真正意义。我今天认真地进行了这次设计，学会了脚踏实地迈开这一步，就是为明天能稳健地在社会大浪潮中翱翔打下坚实的基础。
说实话，毕业设计真是有点累。然而，当我一着手清理自己的设计成果，仔细回味这三个月的心路历程，一种少有的成功喜悦即刻使我倦意顿失。虽然这是我人生中的一点小小的胜利，然而它令我感到自己成熟了许多，令我有了一种“春眠方觉晓”的感悟。
三个月的毕业设计，使我发现了自己所掌握的知识的欠缺，自己综合应用所学专业知识的能力的不足。大学四年来学的这么多知识，今天才知道要想把它变成自己的东西，还需努力。在设计过程中，多亏知道老师不断的指导和勉励，使我充满自信，直到最后完成设计内容。
最后，忠心地感谢杨雪银老师，是你引导了我，是你的敬业精神感动了我，是你的谆谆教诲启发了我，是你的殷切期望鼓励了我。我感谢你今天为我增添了一副坚硬的翅膀。在此致以衷心的感谢！
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参考文献
[1] 孟少农 机械加工手册（1）（第一版）[M]. 北京：机械工业出版社，1995 [2]李益民 机械制造工艺设计简明手册. 北京：机械工业出版社，1994 [3] 孟少农 机械加工手册（2）（第一版）[M]. 北京：机械工业出版社，1995 [4] 赵家齐 机械制造工艺学课程设计指导书（第二版）[M]. 北京：机械工业出版社2001 [5] 李旦等 机床专用夹具图册. 哈尔滨：哈尔滨工业大学出版社，1998 [6] 王先逵 机械制造工艺学[M]. 北京：机械工业出版社，2004
[7] 邹 清 机械制造技术基础课程设计指导教程[M]. 北京：机械工业出版社，2004 [8] 倪森寿 机械制造工艺与装备习题集[M] 北京：机械工业出版社，2003
[9] 张龙勋 机械制造工艺学课程设计指导书及习题[M]. 北京：机械工艺出版社，2003 [10] 张进生，房晓东 机械工程专业课程设计指导[M]. 北京：机械工业出版社，2003 [11] 成大仙 机械设计手册[M]. 北京：化学工业出版社，2002 [12] 王小华 机械夹具图册 . 北京：机械工业出版社，1995
[13]方若愚 金属机械加工工艺人员手册[M]. 北京：机械工业出版社，1996 [14] 王绍俊 机械制造工艺设计手册. 北京：机械工业出版社，1985 [15] 徐鸿本 机械制图 .北京：国家标准局批准，2002
[16] 孙丽媛 机械制造工艺及专用夹具设计指导[M]. 北京：冶金工业出版社，2003 [17] 薛源顺 机床夹具设计[M]. 北京：机械工业出版社，2001
[18] 孟宪栋，刘彤安 机床夹具图册[M]. 北京：机械工业出版社，2002 [19] 赵如福等 金属机械加工工艺人员手册[M]. 北京：机械工业出版社，1990 [20] 郑修本 机械制造工艺学（第二版）. 北京：机械工业出版社，2006
[21] Morgan,M.N,Rowe, W. B., Black, S. C. E. and Allanson,D. R. Machining of Engineering Ceramics[J]. Engineering Manufacture, 1998, 212(B8), 661–669.
[20] Rowe, W. B. Mechanical Engineering in zhe information[J] . Engineering Manufacture, 2001, 215(B4), 473–491.
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附录
Manufacturing Engineering and Technology—Machining
By：Serope kalpakjian Steven R.Schmid
20.9 MACHINABILITY
The machinability of a material usually defined in terms of four factors:
1、Surface finish and integrity of the machined part; 2、Tool life obtained;
3、Force and power requirements; 4、Chip control.
Thus, good machinability good surface finish and integrity, long tool life, and low force and power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone.
Because of the complex nature of cutting operations, it is difficult to establish
relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below. 20.9.1 Machinability Of Steels
Because steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-called free-machining steels.
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Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers in resulfurized steels.
Phosphorus in steels has two major effects. It strengthens the ferrite, causing increased hardness. Harder steels result in better chip formation and surface finish. Note that soft steels can be difficult to machine, with built-up edge formation and poor surface finish. The second effect is that increased hardness causes the formation of short chips instead of continuous stringy ones, thereby improving machinability.
Leaded Steels. A high percentage of lead in steels solidifies at the tip of manganese sulfide inclusions. In non-resulfurized grades of steel, lead takes the form of dispersed fine particles. Lead is insoluble in iron, copper, and aluminum and their alloys. Because of its low shear strength, therefore, lead acts as a solid lubricant (Section 32.11) and is smeared over the tool-chip interface during cutting. This behavior has been verified by the presence of high concentrations of lead on the tool-side face of chips when machining leaded steels.
When the temperature is sufficiently high-for instance, at high cutting speeds and feeds (Section 20.6)—the lead melts directly in front of the tool, acting as a liquid lubricant. In addition to this effect, lead lowers the shear stress in the primary shear zone, reducing cutting forces and power consumption. Lead can be used in every grade of steel, such as 10xx, 11xx, 12xx, 41xx, etc. Leaded steels are identified by the letter L between the second and third numerals (for example, 10L45). (Note that in stainless steels, similar use of the letter L means ―low carbon,‖ a condition that improves their corrosion resistance.)
However, because lead is a well-known toxin and a pollutant, there are serious environmental concerns about its use in steels (estimated at 4500 tons of lead consumption every year in the production of steels). Consequently, there is a continuing trend toward
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