汽车冲压件成形新工艺

介绍了液压拉深、管状内高压成形和热成形等几种新技术在汽车冲压件成形中的应用。通过优化汽车车身生产工艺过程,对不同材料开发新的成形技术,以期达到提高材料利用率,减少零件制造工序,降低成本的目的。     

英文标题,摘要及关键词

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MAIN TOPICS,ABSTRACTS ＆ KEY WORDS

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英文标题,摘要及关键词

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英文标题,摘要及关键词

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板材塑性成形理论和技术在汽车工业中的应用及其发展趋势

依靠冲压工艺成形的汽车外蒙皮件及框架结构件在汽车工业生产中扮演着一个重要的角色 ,并在很大程度上决定着一种新车型能否最终赢得市场。所以 ,对其相关的技术必须给予高度的重视。只有依托高水平的技术支持 ,才能获得高质量的产品。涉及冲压工艺生产的相关技术包括 :板材塑性力学 ,冲压工艺过程的有限元分析(FEA) ,具体的成形工艺设计等。其中 ,塑性力学 ,包含其最基本的屈服准则 ,本构关系 ,大变形过程中其各向异性板材方向特性的再定义 ,以及适合于不同冲压工艺的成形极限图 (FLD)等。而对于有限元模拟 ,其关键的实用技术 ,是了解不同应用程序的使用特点及局限性 ,并找到相关的控制措施。涉及具体的成形工艺 ,则必须以可成形性及经济性为准则进行相关的压边工序及辅助部分的设计 ,并对成形道次进行综合分析 ,以获得经济、高效的成形工艺方案     

工业控制系统发展新技术

随着许多厂商已生产出能结合PC功能和PLC可靠性的可编程自动化控制器(PAC),目前控制系统已逐渐开始采用PAC。本文介绍PAC的起源以及它与PLC和PC的区别,并指出了使用PAC的工业控制未来发展方向。     

汽车技术的进展和零件材料、热处理、表面改性技术动向——车体的轻量化和燃料效率的提高

0 引言 由于世界人口的增加和以金砖四国(巴西、俄罗斯、印度、中国)(BRICS)为代表的发展中国家工业化的进展,环绕地球的环境发生变化,对汽车的制造和使用范围也提出了严格的要求.     

Non‐traditional assessment and maintenance methods for aging concrete structures – technical and non‐technical issues

Based on construction dates and observed time to corrosion induced damage, the future need for repair of reinforced concrete motorway bridges in The Netherlands is predicted. Due to the age distribution and in particular the relatively short life of conventional repairs, the need for maintenance will increase steeply over the next few decades. It appears that a back log of postponed maintenance exists, which aggravates the problem. This steep rise may be mitigated by the application of various modern techniques for assessment, prevention, monitoring, and protection, that each have a good track record but are not widely used. Various factors that oppose the application of such innovations in the area of concrete maintenance are discussed.     

Heat treatment of 319.2 aluminium automotive alloy Part 2, Ageing behaviour

In this part of a two-part study of the heat treatment of 319.2 aluminium alloy, the hardening behaviour upon artificial ageing in the temperature range 155‐220 °C for periods of up to 24 h has been investigated. The test bars used were solution heat treated for 8 h at 515 °C (see Part 1). The results show that peak-ageing is achieved after 24 h at 155 °C or 5 h at 180 °C, giving 253 MPa yield strength, 403 MPa ultimate tensile strength, and 1.2% elongation. Inclusions and oxides have a marginal effect on the yield strength; however, they deteriorate both the ultimate tensile strength and % elongation to levels below those obtained in the as-cast condition. Quality index against ageing time relationships have been discussed in terms of the ageing conditions.