A method for the complex chemicothermal treatment of machine parts and tools

Today the service conditions of the majority of machine parts require not only high tribological properties, but also high corrosion resistance. This combination of properties is obtained by a chemicothermal treatment (CTT) that includes the nitriding and oxidizing of the surface. Development of this method resulted in an ONS (O-oxygen, N-nitrogen, S -sulfur) method that consists of nitriding, oxidizing, and surface saturation with sulfur, nitrogen, and carbon. This paper is devoted to the properties of various steels after ONS.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 9 – 11, February, 1995.     

薄壁类零件加工变形的解决工艺方法

介绍薄壁类零件的加工,通过对筒体段节的特点以及加工进行分析,总结了薄壁类零件加工工艺方法。指出只有根据零件的具体结构特点,设计合理的加工工艺路线、选择合适的刀具、确定合理的切削速度才能真正解决薄壁零件的加工变形。     

The implications of automobile parts supply network structures: A complex network approach

This study investigates the temporal structural transitions of automobile supply networks where, under situations with various possible risks such as economic crises and market globalisation, companies must both work together for sustainable production, and also compete with each other for their own survival. The resulting network complexity is captured by large-scale empirical data, and analysed for the first time using concepts and metrics developed in complex network science. We discuss how network structure reflects the effect of several factors including market fluctuation, product standardisation, technological advancement, and financial interdependencies between companies.     

考虑加工过程的复杂薄壁件加工综合误差补偿方法

针对机器人在空间曲面焊接过程中需要保持焊接速度和焊炬位姿恒定的工艺要求,提出了一种适用于复杂空间曲面焊接机器人的运动规划方法,该方法采用NURBS曲线对三维点云描述的空间轨迹进行光顺逼近,建立机器人配合变位机组成的多自由度焊接系统运动学模型并进行逆运动学求解. 开发了一套完整的复杂空间曲面焊接机器人自动编程系统. 以翻领成型器为例进行了复杂空间曲面焊接机器人的自动编程及焊接试验. 结果表明,文中提出的复杂空间曲面焊接机器人运动规划方法和自动编程系统能够顺利完成焊接任务,且运动平稳,具有良好的焊接轨迹精度.     

Rapid precision casting for complex thin-walled aluminum alloy parts

1 .IntroCtion Seleetive Laser Sintering(SLS)15 an imPortant field ofRaPid PrototyPing(RP),due to its caPability ofProeessinga very wide range ofmaterialsinadireetway.AtPresent,most of sintering materials are nonmetallie,     

A new hybrid electrochemical-mechanical process (PEMEC) for polishing complex and rough parts

A new polishing process for metallic parts has been developed by simultaneously coupling drag finishing and electrochemical polishing. This new hybrid process, called PEMEC, enables an improvement in the surface roughness within some minutes, and at the same time, preserves the shape of the edges. This hybrid process is based on a synergistic effect between abrasive and chemical mechanisms. It has confirmed its suitability to be applied on complex and rough surfaces produced by additive manufacturing SLM parts.     

复杂抛物形零件翻边工艺分析及模具设计

详述了在不完全封闭壳体内翻边成形的工艺分析和模具结构。     

汽车内衬零件复杂多工位连续模设计

汽车内衬零件的形状结构复杂、表面质量要求高、成形轮廓尺寸大,针对其成形过程中易出现滑移、回弹、起皱、拉裂等缺陷的问题,详细地分析了某款汽车内衬零件的冲压工艺性能,制定了包括冲孔、拉深、压凸包、翻边和弯曲等14个工位的成形工艺方案.为避免后期现场模具调试反复进行,在冲压工艺设计的前期,选择CAE分析软件对成形过程和质量缺...     

5A06铝合金复杂盒形件等温锻造工艺研究

针对5A06铝合金复杂盒型件,利用有限元分析软件Deform,确定了先预成形后终成形的等温锻造成形工艺方案。并通过逆向补偿方法设计了预成形及终成形模具。在20 MN锻压机上,先将铝合金板材预锻成预制坯,然后再等温终锻。等温锻造工艺中,模具温度为(450±10)℃,5A06铝合金预制坯温度为(465±10)℃,成形时最大挤压力为14000 k N。等温锻造试验表明;Deform有限元分析对等温锻造成形工艺研究具有较强的指导意义,采用先预成形后终锻成形工艺能大大提高锻件成形质量;此外,5A06铝合金等温锻造盒型件相较于机械加工盒型件,抗拉强度Rm提高到350 MPa,伸长率A提高到25%。     

A new technology for fabricating parts with a complex configuration from powder high-temperature nickel alloys

Conclusions  

平板电视注射模复杂零件的电极设计

分析了平板电视注射模电极设计及实际电加工过程中容易出现的问题,对平板电视后壳清角电极、圆柱形网孔镶件电极和斜壁石墨电极的设计做出了改进,使电极的设计更合理,提高了电加工的效率。     

用于钢铁零件工序间防锈的植酸防锈液研制及其性能

以环保特性优良的植酸为基本成分(150 mg/L),通过添加少量生物缓蚀剂、稀土缓蚀剂等成分作为工序间零件的防锈溶液,对机加工零件经过工序间防锈处理的试样进行湿(相对湿度90%)热(50℃)环境下的加速腐蚀、中性盐雾腐蚀试验,考察机加工钢铁零件经过工序间防锈处理后的防锈性能和电化学行为。试验结果表明:工序间防锈液处理的零件在高温高湿环境下的防锈性能优良。工序间防锈液中的植酸与生物缓蚀剂、稀土缓蚀剂在钢铁零件工序间防锈处理中具有协同效应。经工序间防锈液处理的试样其阻抗谱出现两个容抗弧,且腐蚀电位正移400 mV。     

A surface topography model for automated surface finishing

This paper presents a 3-D surface topography model that has been developed to analyze and represent the spectrum of components of surface topography ranging over shape, waviness and roughness in a way suitable for generating macro- and micro-level automated surface finishing commands. Results of 3-D surface topography analysis such as comparison of desired and actual surface topography must be combinable with surface finishing processes in ways that permit the generation and output of commands, thereby causing the actual surface topography to converge towards a desired surface topography.An efficient filter, 3-D motif filter, with optimal cut-off length has been developed for roughness elements first, and then extended to waviness elements.A neutral surface shape method approximation for the machined surface shape has been proposed. Surface shape error is then eliminated as the deviation of the approximated neutral surface shape and the design surface shape.After the motif filtering, a B-spline fitting is used to represent the surface topography data within each 3-D motif cell after surface shape regeneration. The data reduction technique in 3-D motif filter methods has been shown significantly by reducing a great amount of inspection data to several elements and each element is suitable for use in surface finishing control. Some limitations of the 3-D motif filter method are discussed by the selection of different machined lay direction. The use of the developed 3-D surface topography model on automated surface finishing processes was performed on a platform constituting a 3-axis CNC machining center, inspection probe and a electrical grinder installed on the spindle housing of CNC machining center. Experimental results from an automated surface finishing system (ASFS) with in-process surface topography acquisition for mold and die finishing have shown the optimistic use of the developed surface topography model for industrial applications.     

Combined tube and double sheet hydroforming for the manufacturing of complex parts

Modern lightweight construction, especially in the automotive industry, requires more and more complex components, which can be manufactured in one process step using the hydroforming technology. The combination of the tube and double sheet hydroforming is a new forming process, where a tube and two blanks are formed simultaneously in a die cavity, combining the advantages of both hydroforming variants. This paper deals with the fundamental considerations and investigations related to connection between tube and double sheet. The finite element analysis and laboratory trials were used in order to design the shape of the die cavity and to avoid wrinkles, material tearing and the collapse of the tube section during forming. The paper will also illustrate an analytical model for the prediction of the edge shape in the constrained bulging of a rectangular cup together with several technical solutions, which enabled a complete forming of the investigated part. Finally, the definition of a hydroforming material factor based on the analytical model of the hydraulic bulging process enables the right choice of sheets with different material strength and thickness for the hydroforming of hybrid components.     

Computer-aided torch trajectory generation for automated coating of parts with complex surfaces

The work presented in this paper is concerned with the design and development of an efficient computer software package for off- line programming of robots for spray coating. The developed package (called CA- COATS) allows the spray torch to track a path, maintaining the specified spraying distance and proper orientation relative to the part surface at all points, and thus ensuring uniform coating thickness. This software package is done off- line and is complete in itself, eliminating the need for another computer-aided design database of the base surface (although the package can be made to interface with such a database if so desired). Because the algorithm has no iteration, it is computationally efficient. With minor modifications, this package can also be extended to waterjet coating- removal systems.