Laminated fabrication of 3D queue micro-electrode and its application in micro-EDM

3D micro-electrode used in micro electrical discharge machining (micro-EDM) is difficult to be fabricated. Based on laminated object manufacturing (LOM) process, this paper superimposed multilayer 2D micro-structures together to fit out 3D micro-electrode and applied it in micro-EDM to process 3D micro-cavity mold. Firstly, 100-μm-thick Cu foils were cut by wire-electrical discharge machining (WEDM) to obtain multilayer 2D micro-structures, and then these 2D micro-structures were connected together to fit out 3D micro-electrode through vacuum pressure thermal diffusion welding. Secondly, under the effect of 80-V voltage, 0.2-MHz pulse frequency, 800-ns pulse width, and 4200-ns pulse interval, the 3D micro-electrode was applied in micro-EDM and 3D micro-cavity mold with high surface quality was obtained. Thirdly, in order to reduce the adverse impact of electrode wear on machining precision of 3D micro-cavity mold, 3D queue micro-electrode was used to process the same 3D micro-cavity mold, in which the first electrode is for rough machining and the others for fine machining. Finally, based on the above studies, two kinds of 3D queue micro-electrodes were fabricated, and the 3D micro-cavity molds with surface roughness Ra?=?0.48 μm were obtained through micro-EDM. Compared with the scanning 3D micro-EDM process, the 3D micro-cavity mold can be obtained through up and down reciprocating method of the 3D queue micro-electrode, featuring simple machining process and high efficiency.     

超精密切削的复杂曲面微加工研究

随着微机电和纳米技术的快速发展,复杂形面微小零件的超精密加工显得越来越重要。本文通过对复杂曲面超精密加工的研究,针对金属材料制作的复杂形面微小零件的超精密切削工艺进行了深入研究。     

精密微小型制造理论、技术及其应用

以中间尺度的微小型构件为目标,以传统制造技术为基础,提出精密微小型制造技术概念和主要内涵.提出并实现了高转速数控精密微小型车铣复合加工技术,研究在微小型车铣复合加工中心上进行微小型零件完整性加工的工艺技术及特性.针对超薄、异型微小型金属构件的制造,提出大功率高频群脉冲电化学微小型制造方法和工艺.提出并初步研究基于制造特征仿真的相关理论和建模方法,介绍应用实例.提出基于工艺匹配原则的计算机显微检测技术,介绍关键技术研究进展.     

模具高速切削关键技术研究进展

通过对高速切削技术(HSM)含义的描述,详细介绍了高速切削加工技术的特点、先进性及其在模具加工行业中的应用。与传统的模具加工工艺(普通放电加工EDM)相比较,详细分析了高速切削技术应用于模具加工制造业中的优势,并重点从高速切削机床、加工刀具、加工工艺技术及策略等方面,对高速切削技术应用于模具制造中的关键技术进行了分析探讨。最后综述了模具高速加工中存在的问题并对模具高速切削加工技术在我国的前景进行了展望。     

A computer-aided design system for foot-feature-based shoe last customization

The micro-electrical discharge machining (micro-EDM) process has proved to be an appropriate nonconventional machining method for manufacturing accurate and complex three-dimensional structural micro-features which are difficult to be produced by conventional processes. However, the miniaturisation of the EDM process requests special requirements on the machining equipment. Pulse generators which can produce small input energy pulses and high precision systems are the two major requirements. In this paper, newly developed technologies regarding these aspects are explored with the aid of a commercial micro-EDM machine. By examining the pulses, innovative strategies implemented in the pulse generator are studied. Pulse measurements reveal the correlation between the discharge pulses and the machine parameters in order to provide an overview of process capability. Conclusions are applied on machining of a ceramic composite Si₃N₄-TiN and optimised machining settings for different machining conditions are achieved. Accordingly, applications of two- and three-dimensional micro-structures on different types of materials such as a stainless steel micro-compressor and a ceramic miniature gas turbine are demonstrated. By inspecting the machining geometry and surface integrity, process characteristics of micro-EDM are discussed.     

机械模具制造中数控加工技术的有效性应用分析

现如今,随着我国科学技术水平的提升,机械模具数控加工制造技术也得到了快速的发展,在这种情况下开展机械制造时,也提高了对其他多个方面的要求,比如行面复杂度、结构繁琐度等,总体来说,机械模具数控加工技术在整个模具制造过程中发挥了非常重要的作用,因此,为了能够进一步提高数控加工技术在机械模具制造中的应用效果,本文特对数控加工技术在机械模具制造中的有效应用进行分析,仅供参考。     

A Feasibility Study on the Micro Eletro-Discharge Machining Process for Photomask Fabrication

A feasibility study of micro electro-discharge machining (micro-EDM) technology has been conducted for its possible contri-bution in the photomask industry. A series of experimental runs was performed on three specimens using a micro-EDM system with built-in wire electro-discharge grinding. Different thicknesses of chromium films were coated on borosilicate glass substrates. Unwanted chromium metal was machined through to the transparent glass substrate, leaving behind the desired pattern. In this study, lines were machined at different voltages, using electrodes of 20 _m in diameter, and no significant wear of electrodes was observed. The machined regions on the specimens were quantified in terms of linewidth deviation and light transmission. The experimental results showed that the linewidth deviations for all three specimens are below the 10% cut-off threshold. The best average light transmission obtained from this experiment was 75.8% at 90 V. The results gathered so far, suggests that the application of micro-EDM to produce a photomask is an acceptable process.     

超精密加工技术与直线电动机在超精密加工装备中的应用

超精密加工是多种技术综合的一种加工技术,通过超精密加工能够使被加工零件的形状精度、表面粗糙度和表面完整性达到空前的水平。直线电动机以其独特的优势,在超精密装备中得到更广泛的应用。本文主要针对超精密加工技术与直线电动机在超精密装备中的应用,以及在国内外的发展状况进行了阐述,重点提出了超精密加工技术与直线电动机在加工制造业中应用的明显优势,同时也说明了它们的一些缺点及可行的解决方法。     

谈我国先进制造技术的现状与未来

在介绍我国先进制造技术的发展时,有必要对先进制造技术发展所依赖的国际经济与科技发展趋势及与它密不可分的制造业的发展趋势作一概括的论述。     

5-axis micro milling machine for machining micro parts

This paper presents a PC-based 5-axis micro milling machine, which can be used for machining micro-sized parts, and be easily constructed a low cost. Micro cutting is a method for manufacturing three-dimensional micro parts; however, machine tools for micro machining are expensive. The micro milling machine presented in this paper is mainly composed of commercially available micro stages, and an air spindle and PC-based control board. An effective method for initializing the spindle position is proposed. Test results of the micro milling machine are presented, which include machining of micro walls, micro columns and micro blades.     

机械制造工艺发展现状与未来发展趋势

机械制造工艺是保证机械制造发展的重要基础性技术,重点介绍高科技技术在机械制造领域广泛的应用情况,其中包括自动化控制技术、纳米技术、电磁技术、激光技术等。这给机械制造工艺带来了新的推动力和发展空间,未来的机械制造工艺将向着数字化、精细化、集成化发展。     

薄板微小齿轮落料模的试制与探讨

在薄板微小齿轮落料模的试制过程中 ,分析了凸、凹模的加工方法及其间隙确定、研配等工艺方案的可实施性。采用上、下冲裁法 ,提高变形区静水压力 ,解决了冲裁中出现的齿尖塌陷、毛刺等缺陷。指出适当提高相对变形速度、提高静水压力 ,可有利于改善微小型制件的冲裁质量。     

激光熔覆直接成形金属铸造模具的探讨

探讨激光熔覆金属粉末快速原型技术直接制造铸造用金属模具的问题。文章介绍了这种技术的特点：快速直接制造金属原型，其制件的结构、形状和功能特性都能符合最终用途，可大大缩短产品的开发周期。通过分析砂型金属模具、金属型、压铸型、石蜡模母模和消失模母模等铸造模具的结构特征和在制造上的要求，说明了激光熔覆金属粉末快速原型技术适用于这些铸造模具的制造；指出了在应用中需要进一步轻量化、低耗化，并分别提出了可行的对策。随着各种相关技术的发展及其综台、集成度的提高，激光熔覆金属粉末制造铸造模具的轻量化、低耗化将逐步实现，其应用将更广泛。     

Engineering surface and development of a new DNA micro array chip

This paper proposes a new concept of the ‘engineering surface’, which extends the conventional idea of a functional surface by combining it with micro/nano manufacturing technology. Characteristic features and possibilities of the engineering surface are discussed in detail. This paper reviews studies on micro/nano fabrication technologies for advanced materials and evaluation technology for surface function. New fabrication technologies, micro machining and nano forming, are introduced, which will be basic manufacturing processes of the engineering surface. Also, a new surface evaluation technique is introduced for the surface energy of the nano fabricated surface. Design of a new DNA micro array chip is introduced as an example of applications of the engineering surface. Controllability of surface property by nano fabrication is studied.     

大型水轮机叶片的多轴联动数控加工编程技术

转轮叶片是水轮机能量转换的关键部件，也是最难加工的零件，目前多轴联动数控加工是解决该类大型雕塑曲面零件最有效的加工方法。多轴联动数控加工编程则是实现其高精度和高效率加工的最重要环节。介绍了大型水轮机叶片五轴联动数控加工大型雕塑曲面编程中涉及到的转轮叶片三维造型、刀位轨迹计算、切削仿真、机床运动碰撞仿真、后置变换等关键技术。通过对这些技术的链接和研究，开发实现了大型叶片的多轴联动加工。     

微细电火花加工技术的研究进展

研究和综述了微细电火花加工技术的研究现状和发展趋势。比较分析了常用微细加工与微细电火花加工方法的特点及应用，论述了线电极电火花磨削技术的原理及在微细加工中的作用。结合电火花加工过程中无宏观作用力的特点，论述了微细电火花加工装置微小型化的可行性和几种主要形式。     

微细电火花加工及其关键技术

综述了微细电火花加工的基本原理及最新研究进展。比较了LIGA技术与微细电火花加工的特点与应用。简要分析了微细电火花加工的关键技术：微细电极的在线制作、微进给装置、微小能量的脉冲电源、微小电极的运动轨迹规划、电极的损耗及补偿策略。展望了微细电火花加工在微三维结构加工中的应用前景。     

Fabrication of a metal mold with microstructures using a novel passive-alignment recombining technique

This study presents a novel scheme for manufacturing a large area molds with alignment microstructures electroplated from lateral joining of small area silicon plates. Conventional methods for manufacturing metal molds with nano or microstructures are extremely challenging. Semiconductor fabrication procedures that utilize photolithographic processes to generate nano-scale features easily limit wafer scale. However, a large area silicon mold with small features has been developed. However, its drawbacks were serious misalignment, tilting, and brittleness. This work presents a novel approach for fabricating a metal mold with precisely aligned microstructures. The gap, alignment precision, tilt, and height difference between the two joined plates joined laterally by passive alignment recombining techniques were all on a micro scale. Furthermore, the measurements of the metal molds and Polyvinylchloride (PVC) replicas were extremely similar. Moreover, the scalability of the technique was demonstrated using four small area silicon plates. Consequently, this approach has significant potential for bridging the technological gap between conventional precision machining and photolithography-based micromachining for metal molds exceeding typical wafer size with small features.     

Fabrication of micro rods by twin-mirroring-wire tangential feed micro electrical discharge grinding

In micro electrical discharge machining (micro-EDM), the precision fabrication of cylindrical micro rods is difficult to achieve with a high processing efficiency. In order to overcome this challenge, this paper proposes a new processing method, which is denoted as twin-mirroring-wire tangential feed micro electrical discharge grinding (TMTF-WEDG). The machining principle, characteristics, and realization of the new method are firstly introduced. Then, the advantages of TMTF-WEDG in terms of machining efficiency and accuracy are demonstrated. The experimental results have shown that the machining efficiency can be increased to more than 70% in comparison with conventional tangential-feed wire electrical discharge grinding. It has also been proved that a minimum removal of material corresponding to a reduction of less than 1 μm in the diameter of a micro rod can be obtained by TMTF-WEDG. This considerably helps in improving the accuracy and repeatability of the machining process. A deviation of less than 1 μm on the diameter of a micro rod has been obtained in a length range of 800 μm. The process repeatability in machining five micro rods has been established to be below 2 μm. The proposed method is therefore of great significance for improving the machining efficiency and ensuring a high precision in the shaping process of cylindrical micro rods.     

陶瓷零件增量成形技术的研究进展

陶瓷材料因其优越性能而一直受到广泛关注,但传统的陶瓷零件制造技术工艺复杂、难度大、周期长、成本较高,从而限制了陶瓷材料的应用范围,而3D打印增量成形技术为克服传统技术的不足提供了一种新的途径。介绍了现有陶瓷零件增量成形技术,并从所能达到的密度、强度、收缩率水平几个方面分析了各项技术的优缺点,重点介绍分析了成形与烧结一体化的高致密陶瓷零件的高效增量成形新技术,并指出该一体化成形技术将是陶瓷零件增量制造技术未来的重点研究方向。