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编号无锡太湖学院毕业设计(论文)相关资料题目:汽车发动机附件箱多孔加工专机的设计 信机 系 机械工程及自动化专业学 号: 0923088 学生姓名: 王俊 指导教师:过金超(职称:高级工程师) (职称: )2013年5月25日目 录一、毕业设计(论文)开题报告二、毕业设计(论文)外文资料翻译及原文三、学生“毕业论文(论文)计划、进度、检查及落实表”四、实习鉴定表无锡太湖学院毕业设计(论文)开题报告题目:汽车发动机附件箱多孔加工专机的设计 信机 系 机械工程及自动化 专业学 号: 0923088 学生姓名: 王俊 指导教师:过金超(职称:高级工程师 ) (职称: ) 2012年11月17日 课题来源本课题是广西玉林柴油机厂委托无锡市宏业机械配件厂加工的汽车发动机零件,此种发动机在载重汽车及客车上广泛使用。科学依据(包括课题的科学意义;国内外研究概况、水平和发展趋势;应用前景等)1、工艺是机械产品设计制造过程中十分重要的一个环节,其水平与质量直接影响到产品的最终制造质量及成本运行。2、加工技术正向高度信息化、自动化、智能化的方向发展,各种现代的加工方法也不断地创造和完善,如快速成型技术、激光加工、电加工和射流加工等已相当广泛的应用到加工中去,而这些使工艺设计也带来巨大的进步。3、作为机械专业的本科毕业生采用此类课题可以培养学生认识机械加工生产准备工作是怎样一个过程,可以受到理论与实践相结合的锻炼。研究内容1、机械加工工艺规程的编制,结合具体工厂的条件和发展前景进行考虑。2、同样结合具体工厂的现有生产条件和发展前景设计专用(不少于三付)拟采取的研究方法、技术路线、实验方案及可行性分析采用组织分析零件的具体结构,加工精度要求,表面粗糙度要求,制定出初步的加工方案,然后组织学生下工厂参观、实习、实地了解工厂出现的生产条件,发展展望及具体的生产水平。然后在此基础上编制工艺规程,填写工艺文件,设计专用夹具,待初步完成后,再回工厂征集意见,加以改进,定稿。研究计划及预期成果研究计划:2012年10月12日-2012年12月25日:按照任务书要求查阅论文相关参考资料,填写毕业设计开题报告书。2013年1月11日-2013年3月5日:填写毕业实习报告。2013年3月8日-2013年3月14日:按照要求修改毕业设计开题报告。2103年3月15日-2103年3月21日:学习并翻译一篇与毕业设计相关的英文材料。2103年3月22日-2103年4月11日:工艺规程设计和工艺过程卡、工序卡设计。2103年4月12日-2103年4月25日:工艺计算和夹具设计。2103年4月26日-2103年5月21日:毕业论文撰写和修改工作。预期成果:工艺规程、工艺卡片、工序卡片夹具总图及主要的零件图 设计说明书特色或创新之处工艺规程可以适用于一般中小型工厂的普通通用机床,也能改进后用于专用机床,或加工中心,适用于范围较广。已具备的条件和尚需解决的问题现有广西玉柴机器的生产图样,委托加工工厂的现有生产条件及技术状况,特别是已有的生产经验。目前缺少设计手册、资料等,对检测条件也不够清楚其它资料也缺乏。指导教师意见 指导教师签名:2012 年 11 月 16 日教研室(学科组、研究所)意见 教研室主任签名: 年 月 日系意见 主管领导签名: 年 月 日无锡太湖学院毕业设计(论文)外文资料翻译 信机 系 机械工程及自动化 专业院 (系): 信 机 系 专 业: 机械工程及自动化 班 级: 机械92班 姓 名: 刘昊 学 号: 0923091 外文出处: 机械专业英语教程 附 件: 1.译文;2.原文;3.评分表 2013年5月15日 英文原文Influence factors on the quality of the workpiece surfaceProcessing process on the surface quality of the influenceThe vibration of the process system of the influence on the quality of the surfaceIn mechanical processing process technology system sometimes occur vibration, that is, in the cutting edge tool and workpiece is cutting surface except on the name between cutting motion, but also can appear a cyclical relative motion.Vibration that process system by forming movement of the interference and damage, make processing surface appear chatter marks, increases the surface roughness value, worsening processing surface quality.Cutter geometrical parameters, materials and cutting quality to the surface quality of the influenceThe cutting tool geometric parameters on the surface roughness of the biggest influence is vice PianJiao, the main point PianJiao, arc radius. Under certain conditions, reduce PianJiao, Lord, vice PianJiao point arc radius can reduce surface roughness. Under the same conditions, carbide cutting tools process of surface roughness value less than high speed steel paper cutting knife, and diamond and CBN) tools and better than hard alloy, but because the diamond and iron family affinity materials, it should not be used for processing iron family materials. In addition, the cutting tool before and after the face, cutting knife blade itself directly influence the roughness of the processing the roughness of the surface, therefore, improve the quality of cutting tool, cutting tool and face, cutting knife blade roughness value should be lower than the roughness of the 1 2 levels.Cutting fluid to the influence on the quality of the surfaceCutting fluid cooling and lubrication effect can reduce the cutting process of interface friction, reduce the temperature of cutting zone, the cutting metal surface layer of plastic deformation degree down, restrain the develop the thorn and scales produced in the production of different materials for reasonable choice of cutting fluids can reduce the surface roughness.The workpiece material on the surface quality of the influenceThe workpiece material nature; Processing plastic materials, the cutting tools for metal extrusion produced plastic deformation, and the cutting tool and workpiece forced separation of the torn scraps effect, make the surface roughness value increase. The workpiece material tenacity the better, metal, plastic deformation, the bigger the processing surface is the more the rough. Processing brittle material in the chip broken granular, due to the collapse in broken and endows the machined surface left many pitted surface roughness.General toughness large plastic materials, processing after large surface roughness, and toughness of smaller plastic materials, processing to get smaller after the surface roughness. For the same kind of material, the greater the grain size of the organization, the larger the surface roughness. Therefore, in order to reduce the surface roughness, often in cutting processing of material before quenching and tempering or is the fire of treatment to obtain homogeneous fine grain organization and high hardness.Cutting condition the influence on the quality of the surfaceAnd cutting condition of the relevant process factors, including cutting dosages, cooling lubrication. In low speed processing plastic materials, easy to produce the devolop and scales thorn, so, improve the cutting speed, can reduce the devolop and scales thorn, decreasing part already the surface roughness value; For brittle material, general wont form the devolop and scales thorn, so, cutting speed on the surface roughness basically no influence. The increase speed, plastic deformation also increases, the surface roughness increases, so, reduce the speed can reduce the surface roughness value, however, feeding reduced to certain value, roughness wont obviously decreased. Normal cutting conditions, cutting depth on the surface roughness the impact is not big, therefore, mechanical process cannot select the too small cutting depth.Cutting speed on the surface roughness influenceGeneral at the early choose low speed cutting and finishing choose high speed cutting can reduce the surface roughness. In the medium speed cutting plastic materials, due to easy to produce the devolop, and plastic deformation is bigger, so after processing parts surface roughness is bigger. Usually by low or high speed cutting plastic material, can effectively avoid the devolop of generation, this to reduce table and roughness have positive role.On the surface quality of the grinding effectsThe influence of the grinding wheel grinding wheel granularity the thinner, per unit area grain number grinding, the more of the grinding surface in fine scratches the surface roughness is small; But if too fine granularity, processing to jam wheel it will increase the surface roughness, also easy to produce the ripple and cause burns. The hardness of the grinding wheel should be the right size, its half the longer the better passivation period; The hardness of the grinding wheel is too high, grinding mill is not easy to fall off when grain, make processing surface is of friction, extrusion action intensifies, thus increasing the plastic deformation, making the surface roughness increases, also easy cause burns; But the grinding wheel is too soft, grits too easy to fall off, can make grinding action is reduced, leading to the surface roughness increases, so to select the right grinding wheel hardness. Grinding wheel dressing the higher the quality, the surface of the grinding wheel cutting the blade, cutting the number of all the more the better of the blade contour sex, grinding surface roughness and smaller.The influence of the grinding wheel speed increase dosage, unit time through the processing of grinding surface grain number increase, each star grits is ground to reduce thickness of the metal, the surface area of the residual reduced; And at the same time, improve the grinding wheel speed can also reduce the workpiece material of plastic deformation, these can make processing surface roughness value reduced. Reduce the speed, unit time through the processing of grinding surface grain number increase, the surface roughness decreased; But the low speed, workpiece and grinding wheel contact time long, to the quantity of heat of the increasing, opposite will increase the roughness, may also increase surface burn. Increase grinding depth and longitudinal feeding, the plastic deformation increase, will lead to the surface roughness value increase. Radial feeding increase, the grinding process grinding force and grinding temperature will increase, grinding surface plastic deformation degree increase, which will increase the surface roughness. To guarantee the machining quality in the premise of grinding efficiency increase, will require a higher surface the coarse grinding and fine grinding separately, coarse grinding is used when the big radial direction feeding, fine grinding the radial feeding the smaller when, finally without into to grinding, to get the surface roughness of surface is very small.The workpiece material the workpiece material of hardness, plastic and thermal conductivity on the surface roughness of big effect. Large plastic soft material easy jam grinding wheel, thermal conductivity poor heat resistant alloy easy for the abrasive early caving, will lead to increased grinding surface roughness.In addition, because grinding to the high temperature, reasonable use cutting fluids can reduce the grinding of temperature, reduce burns, can also rushed to fall off the grits and scraps, avoid scratch workpiece, so as to reduce the surface roughness.Affect the surface of physical and mechanical properties of factorsSurface layer cold hardening. The cutting edges obtuse radius increased, and the surface of metal the extrusion of enhanced, plastic deformation intensifies, cold hard to strengthen. After cutting tool knife surface wear increases, the knife surface and after processed surface friction intensified, plastic deformation increase, cold hard to strengthen. Cutting speed increase, cutting tool and workpiece role time is shortened, make plastic deformation expand the depth decreases, and cold hard layer depth decreases. After cutting speed increase, heat cutting in the surface layer effect time also shortened, will make cold hard degree increase. Feeding increases, cutting force also increased, and the surface of the metal plastic deformation intensifies, cold hard effect is strengthening. The workpiece material of plastic is larger and the cold hard phenomenon the serious.Surface layer material metallographic composition change. When cutting the heat was processing surface temperature of phase change after more than temperature, the surface of the metal microstructure will change. Grinding burns when a surface temperature of phase change to millers temperature above, metal surface microstructure occurred change, make the surface of the metal strength and hardness of the lower, and with residual stress produce appear even microscopic cracks, this phenomenon is called grinding burns. Improve grinding burns grinding heat caused by grinding way is the root of the burn, so improving grinding burns by two ways: one is as far as possible to reduce the generation of grinding heat; 2 it is improved cooling condition, make as far as possible the quantity of heat to produce less workpiece. The correct choice grinding wheel reasonable choice of cutting dosages improved cooling conditions.Surface layer residual stress. Produce residual stress of reason: cutting in processing the metal layer and the surface when there were plastic deformation occurs, the surface of the metal to hematocrit increase; Cutting processing, cutting area will have a lot of heat cutting produce; Different analysis of metallographic organization has different density, also have different olume is necessarily affected by the change of connected the matrix of the metal bar, hence residual stress produce. The main work surface eventually process to the choice of methods. Choose the main parts work surface eventually process method, we must consider the main parts of the specific work surface working conditions and the possible damage to the form. In alternating load, the machine parts on the surface of the local micro cracks, because of tensile stress of action to make primary crack expanding, resulting in parts fracture. Improve parts from the view point of fatigue damage resistance, the final process should choose the surface in the surface produces residual stress processing method. In the machining process, tools on the squash and friction make metal materials happen plastic deformation, cause the original residue area of distortion or groove lines deepened, increases the surface roughness. When the medium or medium low cutting speed cutting plastic material, the surface before the sword in easy to form a high hardness of the devolop, it can take the place of the cutting tool, but state very unstable, the devolop generation, grow up and fall off will seriously affect the machined surface roughness value. In addition, in cutting process due to the strong scraps and former knife friction role and tear phenomenon, but also in processing on the surface may produce scale thorn, make processing surface roughness increases.Grinding surface layer analysis of metallographic organization changes and grinding burnsMechanical processing produces in the process of heat cutting processing surface of workpiece will make the rise of temperature of the violently, when the temperature more than the workpiece material metallographic organization changes of the critical temperature, metallographic organization change will occur. In grinding processing, because most grits before cutting Angle is negative, grinding temperature is high, the quantity of heat of generation is much higher than cutting calories at, and grinding heat have 60 to 80% to the workpiece, so very prone to the change of metallographic organization, makes the metal surface hardness and strength of decline, produce residual stress and even cause microcracks, this phenomenon is called grinding burns. Produce grinding burns, processing surface often appear yellow, brown, purple, green and burn color, this is grinding surface oxidation of high temperature in instantaneous film under color. Different burns color, shows that the surface of different levels by burns.Grinding hardened steel, workpiece surface layer due to the role of the instantaneous heat, it may produce the following three metallographic organization changes:If grinding surface layer temperature not over phase transition temperature, but more than martensite transition temperature, then martensite will change to become low hardness of tempering methods, and meanwhile body or body, this call tempering burns.If grinding surface layer temperature more than phase transition temperatures, the martensite transformation for austenitic, at this time without cutting fluids, the grinding surface hardness fell sharply, surface was annealing, this phenomenon is called annealing burns. When dry grinding is easy to produce this kind of phenomenon.If grinding surface layer temperature more than phase transition temperature, but have the full cutting fluid on the cooling, the grinding surface layer will be urgent cold forming secondary hardened martensitic, hardness than tempering martensite high, but the surface layer is very thin, and only a few microns thick, under which the low hardness for tempering saxhlet body and saxhlet body, make the surface layer general hardness still reduce, called quenching burns.Grinding burns improvement measureInfluence factors of grinding burns is grinding dosage, grinding wheel, the workpiece material and cooling conditions. Because grinding heat caused by grinding burns is the root cause of, because this wants to avoid grinding burns, should as far as possible to reduce the heat generated when grinding and decrease as far as possible to the quantity of heat of workpiece. Specific can adopt the following measures:Choosing grinding reasonable dosage cannot use the too big grinding depth, because when grinding depth increases, the plastic deformation is increased, the surface layer and the temperature will increase, burns will also increase; The speed increase, a surface temperature will increase grinding zone, but due to the hot action time reduced, so can reduce the burn.The workpiece material the workpiece material grinding zone of the influence of the temperature of depends primarily on its hardness and strength, toughness and thermal conductivity. The workpiece material hardness, the higher the strength, toughness, the bigger the grinding work when the more consumption, the quantity of heat that produced the more, the easy generation burns; Thermal conductivity of poor material, also easy to appear in the grinding burns.The choice of high hardness of the grinding wheel grinding wheel, passivated grits is not easy to fall off, easy to produce burns, so with soft grinding wheel is better; Choose coarse granularity grinding wheel grinding, not easily by grinding wheel grinding jams, can reduce burned; Combine agent of grinding burns also has a great influence, resin combination age

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