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车铣加工表面粗糙度的形成机理设计说明书及开题,加工,表面,粗糙,形成,机理,设计,说明书,开题

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学生姓名班级指导教师论文（设计）题目车铣加工表面粗糙度的形成机理目前已完成任务1. 完成开题报告和外文翻译，交指导老师审查。2. 查阅大量相关文献。3. 基本完成论文草稿。4. 根据草稿完善开题报告。是否符合任务书要求进度：符合尚需完成的任务1. 完善论文内容2. 熟悉车铣加工的特点3. 完善论文格式能否按期完成论文（设计）：能存在问题和解决办法存在问题1. 进一步研究车铣加工2. 论文的内容不够透彻拟采取的办法1. 查询资料补足内容2. 修改更正不足内容指导教师签 字日期2009 年 5 月1 日教学院长（系主任）意 见 签字： 年 月 日中期进展情况检查表（设计）任务书题目名称车：车铣加工表面粗糙度的形成机理学生姓名所学专业学号指导教师姓名所学专业职称完成期限 20XX 年 2 月 16 日至 20XX 年 6 月 7 日一、论文（设计）主要内容及主要技术指标1 掌握车铣加工的基本原理及其特点；2 分析普通车削外圆的表面粗糙度形成机理，并画出工艺参数对表面粗糙度的影响曲线。借助数值模拟软件对普通车削的表面粗糙度形成过程进行模拟；3分析车铣外圆的表面粗糙度形成机理，并画出工艺参数对表面粗糙度的影响曲线。借助数值模拟软件对普通车削的表面粗糙度形成过程进行模拟；4 比较车削和车铣外圆的加工特点，及其表面粗糙度的基本影响因素，提出改善两者表面粗糙度的基本方法和措施。二、 毕业论文（设计）的基本要求1 毕业设计报告：有400字左右的中英文摘要，正文后有20篇左右的参考文献，其中正文中要引用5篇以上文献，并注明文献出处。2 有不少于2000汉字的与本课题有关的外文翻译资料。3 毕业设计字数在20000字以上。4 程序清单和图纸。5 作品及照片。三、毕业论文（设计）进度安排1 上学期末，下达毕业设计任务书。2 第1-2周，撰写开题报告，指导教师审核开题报告和设计方案。3 第3-10周，毕业设计单元部分设计。4 第11周，毕业设计中期检查。5 第12-14周，设计仿真、程序调试、线路板制作调试，整理、撰写毕业设计报告。6 第15-16周，上交毕业设计报告，指导教师、评阅教师审查、评阅设计报告，毕业设计答辩资格审查。毕业设计答辩，学生修改整理设计报告。车 床车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。车削很少在其他种类的机床上进行，而且任何一种其他机床都不想车床那样方便地进行车削加工。由于车床还可以用来钻孔和铰孔，车床的多功能性可以使工件在一次装夹中进行几种加工。因此，在生产中使用的各种车床比任何种类的机床都多。普通车床：普通车床作为最早的金属切削机床中的一种，目前仍然有许多有用的和人们所需要的特性。现在，这些机床主要用在规模较小的工厂中，进行小批量的生产，而不是进行大批量的生产。普通车床的加工偏差主要取决于操作者的技术熟练程度。设计工程师应该认真的确定由熟练工人在普通车床上加工的试验零件的公差。在把试验零件重新设计为生产零件时，应该选用经济的公差。转塔车床：对生产加工设备来说，目前比过去更着重评价是否具有精确的和快速的重复加工能力。应用这个标准来评价具体的加工方法，转塔车床可以获得较高的质量评定。在为小批量的零件（100200件）设计加工方法时，采用转塔车床是经济的。为了在转塔车床上获得极可能小的公差值，设计人员应该尽量将加工工序的数目减至最少。自动螺丝车床：自动螺丝车床通常被分为以下几种类型：单轴自动、多轴自动和自动夹紧车床。自动螺丝车床最初是用来对螺钉和类似的带有螺纹的零件进行自动化和快速加工的。但是。这种车床的用途早就超过了这个狭窄的范围。现在，它在许多类型的精密零件的大批量生产中起着重要的作用。车床的基本部件有：床身、主轴箱部件、尾架部件、溜板部件丝杠和光杠。 床身是车床的基础件。它通常是由于经过充分正火或时效处理的灰铸铁或者球墨铸铁之城。它是一个兼顾的刚性框架，所有其他基本部件都安装在车床身上。通常在床身上有内外讲足平行的导轨。有些制造厂对全部四条导轨都采用导轨尖顶朝上的三角形导轨（即山形导轨），而有的制造厂则在一组中或者两组中都采用一个三角形导轨和一个矩形导轨。导轨要经过精密加工，以保证其直线度精度。为了抵消磨损和擦伤，大多数现代机床的导轨式经过表面淬硬的，但是在操作时还应该小心，以避免损伤导轨。导轨上的任何误差，常常意味着整个机床的精度遭到破坏。 主轴箱安装在内导轨的固定位置上，一般在床身的左端。它提供动力，并可是工件在各种速度下回转。它基本上由一个安装在精密轴承中的空心主轴和一系列变速齿轮-类似于卡车变速箱所组成。通过变速齿轮，主轴可以在许多种转速下旋转。大多数车床由818种转速，一般按等比级数排列。而且在现代机床上只需按动2-4个手柄，就能得到全部转速。一种正在增长的趋势是通过电气的活着机械的装置进行无极变速。由于机床的精度在很大程度上取决于主轴，因此，主轴的结构尺寸较大，通常安装在预紧后的重型圆锥滚子轴承或球轴承中。主轴中有一个贯穿全长的通孔，长棒料可以通过该孔送料。主轴孔的大小是车床的一个重要尺寸，因为当工件必须通过主轴孔供料时，它确定了能够加工的棒料毛坯的最大尺寸。尾架部件主要有三部分组成。底板与床身的内导轨配合，并可以在导轨上做纵向移动。底板上有一个可以使整个尾架部件夹紧在任意位置上的装置。尾架体安装在底板上，可以沿某种类型的键槽在底板上横向移动，使尾架能与主轴箱中的主轴对正尾架的第三个组成部分是尾架套筒，它是一个直径通常大约在51-76mm（23英寸）之间的钢制空心圆柱体。通常手轮和螺杆，尾架套筒可以在尾架体中纵向移入和移出几英寸。车床的规格用两个尺寸表示。第一个称为车床床面上最大加工直径。这是在车床上能够旋转地工件的最大直径。它大约是两顶尖连线与导轨上最近点之间距离的两倍。第二个规格尺寸是两顶尖之间的最大距离。车床床面上最大加工直径表示在车床上能够车削的最大工件直径，而两顶尖之间的最大距离则表示在车床上能够车削的最大工件直径，而两顶尖之间的最大距离则表示在两个顶尖之间能够安装的工件的最大长度。普通车床是生产中最经常使用的车床种类。它们是具有前面所叙述的所有那些部件的重载机床，并且除了小刀架之外，全部刀具的运动都有激动进给。它们的规格通常是：车床床面上最大加工直径为305610mm（1224英寸）；两顶尖之间距离为6101219mm（2448英寸）。但是，床面上最大加工直径达到1270mm（50英寸）和两顶尖之间距离达到3658mm（12英寸）的车床也并不少见。这些车床大部分都有切削盘和哟个安装在内部的冷却系统。小型的普通车床车床床面最大加工直径一般不超过330mm（13英寸）-其中一些也可以被设计成台式车床，即床身可安装在工作台或柜子上。虽然普通车床很有很多用途，是很有用的车床，但是更换和调整刀具以及测量工件花费很多时间，所以它们不适合在大量生产中应用。通常，它们的实际加工时间少于其加工时间的30%。此外，需要技术熟练地工人来操作普通车床，这种工人的工资高而且很难雇到。然而，操作工人的大部分时间却花费在简单的重要调整和观察切削产生过程上因此为了减少或者完全不雇佣这类熟练工人，转塔车床、螺纹加工车床和其他类型的半自动和自动车床已经很好地研制出来，并已经在生产中得到广泛的应用。LathesLathes are machine tools designed primarily to do turning, facing, and boring. Very little turning is done on other types of maching tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the workpiece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.Engine Lathes:The engine lathe, one of the oldest metal remmoval machines, has a number of useful and highly desirable attributes. Today these lathes are used primarly in small shops where smaller quantities rather than large production runs are encountered.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been poroduced on the engine lathe by a skilled operator. In redesigning an experimental part of production, economical tolerances should be used.Turret Lathes:Production machining equipmnt must be evaluated now, more than ever before, in terms of ability to repeat accurately now,more than ever before, in terms of ability to repeat accurateal and rapidly. Applying this criterion for establishing the production qualification of specific method, the turret lathe merits a high rating.In desingning for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turret lathe. The designer should strive for a minimum of operations.Automatic Serew Machines:Generally, automtic screw machines fall into several categories; single-spindle automatics,mulltiple-spindle automatics production of screws and similar threded part,the automatic screw machine has long since cxceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts.The essential components of a lathe are the bed, headstock assembly, tailstock assembly, carriage assembly, and the leadscrew and feed rod.The bed is the backbone of a lathe. It usually is made of well-noremalized or aged gray or nodular cast iron and provides a heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bad,usually on the upper side. Some makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets. Theyare precision machined to assure accuracy of alignment. On most modern lathes the ways are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.The headstock is mounted in a fixed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the work at various speeds. Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gearssimilar to a truck transmissionthrough which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An incereasing trend is to provide a continuousiy variable speed range through electrical or mechanical drives.Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construcition and mounted in heavy bearings,usually prealoaded tapered roller or ball types.The spindle has a hole extending through its length, through which long bar stock can be fed. The size of this hole is an important dimension of a lathe because it determines the maximum size of bar stock that can be machined when the material must be fed through spindle.The tailstork assembly consists, essentially, of three part. A lower casting fits on the inner ways of the bed and can slide longitudinlly thereon, with a means for clamping the entire assembly in any desired location. An upper casting fits on the lower one and can be moved transversely upon it,on some type of keyed ways, to permint alingning the tailstock and headstock spindles. The third major component of the assembly is the tailstock quill. The is a hollow steel cylinder, usually about 51 to 76mm in diameter, that can be means of a handwhell and screw. The size of a lathe is designated by two dimensions. The first is known as the swing. This is the maximum diamenions. The first is known as the swing. This the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways. The second size dimension is the maximum diameter between centers. The swing thus indicates the maximum workpiece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of workpiece that can be mounted between centers.Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610mm swing and from 610 to 1219mm center distances, but swing up to 1270mm and center distances up to 3658mm are not uncommon. Most have chip pans abd a built-in coolant circulating system. Smaller engine latheswith swings usually not over 330mm also are available in bench type, designed for the bed to be mounted on a bench or cabinet.Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the workpiece, they are not suitable for quantity production. Often the actual chipproduction time is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations,and such persons are costly and often in short supply. However, much of the operators time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amount of skilled labor that is required, turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highily developed and are widely used in manufacturing.课题审核表院（系）名称专业名称指导教师姓名及职称课题名称车铣加工表面粗糙度的形成机理课题来源自选课题立题理由和所具备的条件切削参数与加工零件表面质量关系密切。为了掌握微小型车铣加工的表面粗糙度变化规律,对微小型车铣加工的铣削转速、工件转速、轴向进给量以及切削深度等四个独立的重要切削参数进行试验研究。试验结果表明,铣削转速和工件转速的变化对粗糙度值的影响最明显的,铣削转速越高表面粗糙度值越低,工件转速提高表面粗糙度增大,也就是说铣削转速和工件转速的变化对粗糙度值的影响程度刚好相反。车铣技术是近年来发展起来的一种先进的金属切削技术.由于车铣加工可以大幅度提高切削加工的效率和质量,缩短生产周期,降低加工成本,这项技术已经成为金属切削领域的研究热点.随着科学技术的不断进步,各种高强度、超高强度等材料的广泛使用给切屑的控制带来了更大的困难.车铣加工是间断切削,因此,无论加工何种材料的工件都能得到较短的切屑,易于自动除屑,可以应用车铣技术粗加工外圆以取代现有的车削外圆工艺.切屑形成机理的研究既是切削机理研究的重要组成部分,也是切削机理研究的基础.教研室审批意见教研室主任签字： 年 月 日毕业论文（设计）工作领导小组审批意见组长签字： 年 月 日注：本表经教务处复审后存院（系）备查XXX20XXX（设计）论文题目：车铣加工表面粗糙度的形成机理 学生姓名： 所在院系： 所学专业： 导师姓名： 完成时间： 20XX年 5 月 20日车铣加工表面粗糙度的形成机理 摘 要通过对车削与车铣加工的比较，分析车铣加工时的一些特点及一般的加工工序与加工步骤。综合考虑了刀具几何参数、刀具与工件的相对运动以及切削用量对已加工表面轴向残留面积高度的影响，建立了正交车铣已加工表面轴向残留面积高度的理论计算模型和计算公式，并据此提出了已加工表面粗糙度理论值得计算方法。研究结果表明，理论轴向残留面积高度是影响实际正交车铣已加工表面粗糙度的主要因素。关键词：切削；车铣；已加工表面粗糙度 Formation Mechanism of Surface Roughness in Turn-milling Process ABSTRACTHight speed turn-milling technology is an advanced machining technology , which can make the turning workpiece be cut effciently and pricisely .The process of forming surface is complex , so the research on surface roughness of machined workpiece with theory and experiment is very important .The influence of the cutter geometry parameters , the relative movement and cutting regime on the axial residual areas height is taken into account synthetically .The theoretical calculating model and formula can be used to calcul ate the axtial residual areas height of the machined workpiece by high speed orthodgonal turn-milling are founded . On the basis of this , the method by which the theoretical surface roughnss of machined workpiece can be calculated is given .The experiment results show that theoretical axial residual areas height is the main factor that influences the theoretical surface roughness of workpiece machined by high sp or thodgonal turn-milling .Key words: High speed cutting ; High speed turn-milling ; Machined surface roughness开题报告题目名称：车铣加工表面粗糙度的形成机理学生姓名专业学号指导教师姓名所学专业职称完成期限 20XX 年 2 月 16 日至 20XX 年 6 月 7 日一、选题的目的意义切削参数与加工零件表面质量关系密切。为了车铣加工的表面粗糙度变化规律,对车铣加工的铣削转速、工件转速、轴向进给量以及切削深度等四个独立的重要切削参数进行试验研究。通过分析表明，铣削转速和工件转速的变化对粗糙度值的影响最明显的,铣削转速越高表面粗糙度值越低,工件转速提高表面粗糙度增大,也就是说铣削转速和工件转速的变化对粗糙度值的影响程度刚好相反。二、国内外研究现状车铣加工技术是由德国于20世纪80年代最早研究开发的。目前，对车铣技术的研究主要集中在道具的磨损机理、表面质量和加工表面的完整性、切削形成机理以及硬质材料切削等方面。对滚柱轴承座圈进行了高速车铣加工，研究了轴向车铣和正交车铣中切削条件、刀具和工件相对位置以及刀具几何形状等几何精度和加工表面质量的影响，加工表面粗糙度达到0.5以下。美国研究了高硬度材料的取、进给量的优化，以及车铣加工中切削的形成机理。当以优化的参数用CBN刀