超精密加工技术文献综述

摘要：超精密加工是获得高形状精度、表面精度和表面完整性的必要手段。随着对产品质量和多样化的要求日益提高，对超精密加工提出更多、更高的要求。超精密加工技术已成为包含当代最新科技成果的一个复杂系统工程。介绍超精密加工技术的国内外研究现状、发展过程与趋势以及未来应研究开发的重要科学技术问题。分析我国在超精密加工领域中存在的主要问题以及与国外先进技术的差距，对超精密加工的技术发展趋势进行预测，提出我国本领域基础研究、技术及产业发展策略与对策。

关键词：超精密加工；研究现状；发展趋势；

Literature Review of Ultra-precision

Machining

Abstract:Ultra-precision machining is essential method for obtaining the highest quality in terms form accuracy, surface finish Ultra-precision machining is essential method for obtaining the highest quality in terms of form accuracy, surface finish and surface integrity. As the higher requirements of quality and diversifications for products are put forward, it is essential to improve the precision and efficiency of ultra-precision machining. Ultra-precision machining has become a complicated systems engineering, which involves more and more last research fruits. The conception, application fields, present research status, development tendency, and the key issues of future researches on scientific and technological of ultra-precision machining are introduced in this paper.The main problems and miss distance from the advanced technologies of China in ultra-precision machining field are analyzed. In the same time, the probable further trend of ultra-precision machining is forecasted, and the developing countermeasure and strategy of fundamental research, technologies and industry in China are given. Keywords: Ultra-precision machining Present research status Development tendency

0引言

超精密加工技术始终采用当代最新科技成果来提高加工精度和完善自身，所以“超精密”的概念随科技的发展而不断更新。目前超精密加工技术是指加工的尺寸、形状精度达到亚微米级，加工表面粗糙度达到纳米级的加工技术的总称。目前超精密加工技术在某些应用领域已经延伸到纳米尺度范围，其加工精度已经接近纳米级，表面粗糙度已达到10-1nm级。目前的超精密加工，

以不改变工件材料的物理特性为前提，以获得极限的形状精度、尺寸精度、表面粗糙度、表面完整性为目标。超精密加工目前包括四个领域：①超精密切削加工；②超精密磨削加工；③超精密抛光加工；④超精密特种加工（如电子束、离子束加工）。

1 国内外发展现状

1.1 国际上本领域发展状况

超精密加工发展到今天，已经取得了重大进展，超精密加工已不再是一种孤立的加工方法和单纯的工艺问题，而成为一项包含内容极其广泛的系统工程。影响超精密加工精度的主要因素包括：超精密机床、超精密加工工具(刀具、磨具、磨料等)、超精密加工工艺、被加工材料、夹具、在线检测与误差补偿、超精密加工环境(包括恒温、隔振、洁净控制等)。只有将各个领域的最新技术成就集成起来，才有可能实现超精密加工。

超精密加工的发展经历了如下三个阶段。

(1)20世纪50年代至80年代为技术开创期。这一时期，美国率先发展了以单点金刚石切削(Single point diamond turning, SPDT)为代表的超精密加工技术，用于航空航天、国防、天文等领域激光核聚变反射镜、球面、非球面大型零件的加工。美国的联合碳化公司、荷兰飞利浦公司和美国 LL国家实验室陆续推出各自的超精密金刚石车床，用于铜、铝等软金属的加工，加工形状较只限于轴对称形状的工件例如非球面镜等，且只有少数大公司与研究单位的试验研究。

(2)20世纪80年代至90年代进入民间工业的应用初期。美国的摩尔公司、普瑞泰克公司，日本的东芝和日立，以及欧洲的克兰菲尔德等公司在政府的支持下，将超精密加工设备的商品化，开始用于民用精密光学镜头的制造。单超精密加工设备依然稀少而昂贵，主要以专用机的形式订制。在这一时期还出现了可加工硬质金属和硬脆材料的超精密金刚石磨削技术及磨床，但其加工效率无法和金刚石车床相比。20世纪80年代后期，美国投入了巨额资金和大量人力，由LL国家实验室研制出的大型光学金刚石车床，实现了大型零件的微英寸超精密加工，该设备也成为超精密加工机床的典型代表。

(3)20世纪90年代后，民用超精密加工技术逐渐成熟。在汽车、能源、医疗器材、信息、光电和通信等产业的推动下，超精密加工技术广泛应用于非球面光学镜片、超精密模具、磁盘驱动器磁头、磁盘基板、半导体基片等零件的加工。随着超精密加工设备的相关技术，例如精密主轴部件、滚动导轨、静压导轨、微量进给驱动装置、精密数控系统、激光精密检测系统等逐渐成熟，超精密加工设备成为工业界常见的生产设备。此外，设备精度也逐渐接近纳米级水平、可加工工件的尺寸范围也变得更大，应用越来越广泛。随着数控技术的发展，还出现了超精密五轴铣削和飞切技术。已经可以加工非轴对称非球面等复杂零件。目前世界上的超精密加工强国以欧美和日本为先，但其发展重点各有侧重。欧美特别是美国，不断投入巨额经费，对大型紫外线、X射线

探测望远镜的大口径反射镜的加工进行研究。如美国NASA推动的太空开发计划，以制作1m以上反射镜为目标，目的是探测X射线等短波(0.1～30.0nm波长)。由于X射线能量密度高，必须使反射镜表面粗糙度达到?级来提高反射率。目前此类反射镜的材料为质量轻且热传导性良好的碳化硅，但碳化硅硬度很高，对超精密加工技术提出了非常高的要求。日本对超精密加工技术的研究相对欧美起步较晚，但发展很快。日本超精密加工主要侧重于于计算机硬盘磁片、办公设备用多面镜，非球面透镜光学器件的等大批量民用产品的超精密加工。目前，日本在声、光、图像、办公设备中的小型、超小型电子和光学零件的超精密加工方面具有优势。

1.2 国内本领域发展状况

我国1965年研制出镜面外圆磨床，加工圆度优于0.3μm，表面粗糙度Ra0.01μm以下。1968年研制成功单晶金刚石镜面车床，可使黄铜件的表面粗糙度达Ra0.025μm以下。20世纪70年代后期制成了高精度磁盘车床，主轴回转精度值优于0.2μm。进入20世纪80年代后，各个行业相继投入了更多的人力物力对超精密加工技术与装备进行了深入研究，陆续研制成功了超精密加工设备，特别是在20世纪90年代后期多家单位相继研制成功了非球面超精密加工设备，这标志了我国超精密加工设备的水平上到了一个新的台阶。

哈尔滨工业大学是国内最早从事超精密加工技术研究的单位之一，于1996年研制出了亚微米级的超精密机床，并在微纳米切削过程的加工机理、刀具磨损破损机制、脆性材料超精密切削去除机制等方面开展了大量的研究工作，2006年研制成的大平面超精密铣床，已用于激光核聚变关键零件铁电磷酸二氢钾晶体的超精密加工。北京机床研究所是国内进行超精密加工技术研究的主要单位之一，研制的NAM-800型纳米数控车床是新一代纳米级加工机床，控制系统分辨率为5nm、定位精度为±0.2μm/400mm、重复定位精度为±0.1μm/100mm。北京航空精密机械研究所在超精密切削加工及其装备方面形成了自己的特色，研制出Nanosys-300非球曲面超精密复合加工系统。CCOS技术方面比较有代表性的装备是长春光机所先后研制的数控非球面加工中心FSGJ-I、FSGJ-II、FSGJ-III 和国防科技大学于2002年研制的集铣磨成型、研磨抛光、接触式检测于一体的光学非球面复合加工机床AOCMT。中国科学院长春光机所利用FSGJ-II将一块600mm×300 mm的SiC离轴非球面反射镜加工到面形精度RMS13nm；国防科技大学使用AOCMT将φ500mmf/3抛物面反射镜面形精度加工到了RMS9.4nm。国内有多家单位对MRF进行了研究，例如国防科技大学于2006年研制了可加工1m 口径的MRF设备KDMRF-1000，最近利用该设备加工了一块φ200mmf/1.6的光学玻璃抛物面镜，获得了RMS0.009λ的精度；哈尔滨工业大学孙希威等利用MRF加工了R41.3mm、φ20mm的K9光学玻璃球面，获得了表面粗糙度8.44nm、面形精度P-V 57.9nm的表面。国内对IBF进行研究的单位主要是国防科技大学戴一帆等于 2006 年研制成具备非球面加工能力的IBF 设备KDIFS-500，可加工的最大工件为φ500mm，并利

用该设备加工的平面、球面和非球面面形精度RMS 值均达到了纳米量级，例如将一块初始值为48.6nm的φ200mm f/1.6非球面镜面形精度修正到了6.1nm。此外，苏州大学和国防科技大学分别进行了FJP、MJP的研究，苏州大学利用 FJP 装置将一块φ90mm的非球面镜面形精度加工到了P-V0.36λ，表面粗糙度达到Ra2.25nm。哈尔滨工业大学对大气等离子体抛光进行了研究，针对单晶硅片的加工试验获得了1.46mm3/min的材料去除率和Ra0.6nm的表面粗糙度。中国科学院成都光电所和南京天文光学技术研究所对SLP进行了研究，哈尔滨工业大学和浙江工业大学对气囊抛光进行了研究，都取得了可喜的进展。湖南大学和浙江工业大学在联合开展智能抛光技术与装备、球体超精密高效加工技术与成套数控装备、半固着磨粒高效超精密加工技术等方面的研发工作取得了多项有价值的成果。

2 本领域发展趋势和预测

随着超精密加工技术在民品中的广泛应用，加工的高精度、高质量、高效率、低成本以及批量加工的一致性显得越来越重要。今后，超精密切削和磨削将追随着超精密抛光的高精度、高质量，同时，超精密抛光在追随切削和磨削高效率的同时，向切削磨削加工难以达到的更高精度和质量发展。当前超精密加技术如 CMP、EEM 等虽能获得极高的表面质量和表面完整性，但加工效率不高。超精密切削、磨削技术虽然加工效率高，但无法获得如 CMP、EEM 的加工精度和表面质量。探索能兼顾效率与精度的加工方法，成为超精密加工领域研究人员追求的目标。CMG、SFAM 方法的出现即体现了这一趋势，另一方面表现为电解磁力研磨、磁流变磨料流加工等复合加工方法的诞生。超精密加工技术总的发展趋势是：

1)大型化、微小型化、数控化、智能化的

加工装备；

2)复合化、无损伤加工工艺；

3)超精密、高效率、低成本批量加工；

4)在生产车间大量应用的高精度低成本

专用检测装置。

参考文献：

[1]孙希威，张飞虎，董申，等. 磁流变抛光去除模型及驻留时间算法研究[J]. 新技术新工艺，2006(2)：73-75.

[2]戴一帆，周林，解旭辉，等. 应用离子束进行光学镜面确定性修形的实现[J]. 光学学报，2008，28(6)：1 131- 1 135.

[3]袁巨龙，王志伟，文东辉，等. 超精密加工现状综述[J]. 机械工程学报，2007，43(1)：35-48.

[4]中国科学技术协会，中国机械工程学会. 2008- 2009 机械工程学科发展报告(机械制造)[M]. 北京：中国科学技术出版社，2009.

建筑类外文文献及中文翻译

forced concrete structure reinforced with an overviewRein Since the reform and opening up, with the national economy's rapid and sustained development of a reinforced concrete structure built, reinforced with the development of technology has been great. Therefore, to promote the use of advanced technology reinforced connecting to improve project quality and speed up the pace of construction, improve labor productivity, reduce costs, and is of great significance. Reinforced steel bars connecting technologies can be divided into two broad categories linking welding machinery and steel. There are six types of welding steel welding methods, and some apply to the prefabricated plant, and some apply to the construction site, some of both apply. There are three types of machinery commonly used reinforcement linking method primarily applicable to the construction site. Ways has its own characteristics and different application, and in the continuous development and improvement. In actual production, should be based on specific conditions of work, working environment and technical requirements, the choice of suitable methods to achieve the best overall efficiency. 1、steel mechanical link 1.1 radial squeeze link Will be a steel sleeve in two sets to the highly-reinforced Department with superhigh pressure hydraulic equipment (squeeze tongs) along steel sleeve radial squeeze steel casing, in squeezing out tongs squeeze pressure role of a steel sleeve plasticity deformation closely integrated with reinforced through reinforced steel sleeve and Wang Liang's Position will be two solid steel bars linked Characteristic: Connect intensity to be high, performance reliable, can bear high stress draw and pigeonhole the load and tired load repeatedly.

精密和超精密加工的应用和发展趋势

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超精密加工技术简介论文学校：XXXXX 学院：XXXX 班级：XXXXX 专业：XXXXX 姓名：XXXX 学号：XXXX 指导教师：XXX

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外文原文 Study on Human Resource Allocation in Multi-Project Based on the Priority and the Cost of Projects Lin Jingjing , Zhou Guohua SchoolofEconomics and management, Southwest Jiao tong University ,610031 ,China Abstract----This paper put forward the affecting factors of project’s priority. which is introduced into a multi-objective optimization model for human resource allocation in multi-project environment . The objectives of the model were the minimum cost loss due to the delay of the time limit of the projects and the minimum delay of the project with the highest priority .Then a Genetic Algorithm to solve the model was introduced. Finally, a numerical example was used to testify the feasibility of the model and the algorithm. Index Terms—Genetic Algorithm, Human Resource Allocation, Multi-project’s project’s priority . 1.INTRODUCTION More and more enterprises are facing the challenge of multi-project management, which has been the focus among researches on project management. In multi-project environment ,the share are competition of resources such as capital , time and human resources often occur .Therefore , it’s critical to schedule projects in order to satisfy the different resource demands and to shorten the projects’duration time with resources constrained ,as in [1].For many enterprises ,the human resources are the most precious asset .So enterprises should reasonably and effectively allocate each resource , especially the human resource ,in order to shorten the time and cost of projects and to increase the benefits .Some literatures have

精密和超精密加工现状与发展趋势

精密和超精密加工现状与发展趋势一、精密和超精密加工的概念与范畴通常，按加工精度划分，机械加工可分为一般加工、精密加工、超精密加工三个阶段。目前，精密加工是指加工精度为1~0.1μ;m，表面粗糙度为Ra0.1~0.01μ;m的加工技术，但这个界限是随着加工技术的进步不断变化的，今天的精密加工可能就是明天的一般加工。精密加工所要解决的问题，一是加工精度，包括形位公差、尺寸精度及表面状况；二是加工效率，有些加工可以取得较好的加工精度，却难以取得高的加工效率。精密加工包括微细加工和超微细加工、光整加工等加工技术。传统的精密加工方法有砂带磨削、精密切削、珩磨、精密研磨与抛光等。 a. 砂带磨削是用粘有磨料的混纺布为磨具对工件进行加工，属于涂附磨具磨削加工的范畴，有生产率高、表面质量好、使用范围广等特点。 b. 精密切削，也称金刚石刀具切削(SPDT)，用高精密的机床和单晶金刚石刀具进行切削加工，主要用于铜、铝等不宜磨削加工的软金属的精密加工，如计算机用的磁鼓、磁盘及大功率激光用的金属反光镜等，比一般切削加工精度要高1~2个等级。 c. 珩磨,用油石砂条组成的珩磨头，在一定压力下沿工件表面往复运动，加工后的表面粗糙度可达Ra0.4~0.1μ;m，最好可到Ra0.025μ;m，主要用来加工铸铁及钢，不宜用来加工硬度小、韧性好的有色金属。 d. 精密研磨与抛光通过介于工件和工具间的磨料及加工液，工件及研具作相互机械摩擦，使工件达到所要求的尺寸与精度的加工方法。精密研磨与抛光对于金属和非金属工件都可以达到其他加工方法所不能达到的精度和表面粗糙度，被研磨表面的粗糙度Ra≤0.025μ;m加工变质层很小，表面质量高，精密研磨的设备简单，主要用于平面、圆柱面、齿轮齿面及有密封要求的配偶件的加工，也可用于量规、量块、喷油嘴、阀体与阀芯的光整加工。 e. 抛光是利用机械、化学、电化学的方法对工件表面进行的一种微细加工，主要用来降低工件表面粗糙度，常用的方法有：手工或机械抛光、超声波抛光、化学抛光、电化学抛光及电化学机械复合加工等。手工或机械抛光加工后工件表面粗糙度Ra≤0.05μ;m，可用于平面、柱面、曲面及模具型腔的抛光加工。超声波抛光加工精度0.01~0.02μ;m，表面粗糙度Ra0.1μ;m。化学抛光加工的表面粗糙度一般为Ra≤0.2μ;m。电化学抛光可提高到Ra0.1~0.08μm。超精密加工就是在超精密机床设备上，利用零件与刀具之间产生的具有严格约束的相对运动，对材料进行微量切削，以获得极高形状精度和表面光洁度的加工过程。当前的超精密加工是指被加工零件的尺寸精度高于0.1μm，表面粗糙度Ra小于0.025μm，以及所用机床定位精度的分辨率和重复性高于0.01μm的加工技术，亦称之为亚微米级加工技术，且正在向纳米级加工技术发展。超精密加工包括微细加工、超微细加工、光整加工、精整加工等加工技术。微细加工技术是指制造微小尺寸零件的加工技术；超微细加工技术是指制造超微小尺寸零件的加工技术，它们是针对集成电路的制造要求而提出的，由于尺寸微小，其精度是用切除尺寸的绝对