权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

New methodology of springback compensation for Advanced High Strength Steels based on geometrical modifications

基于几何修改的先进高强度钢回弹补偿新方法

基本信息

批准号：
267134330
负责人：
Professor Dr.-Ing. Mathias Liewald
金额：
--
依托单位：
Institut für Umformtechnik (IFU)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2015
资助国家：
德国
起止时间：
2014-12-31 至 2018-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/267134330?language=en
关键词：
New methodology springback compensation Advanced

项目摘要

Nowadays, the automotive industry is challenged by increasing environmental regulations as well as continuously enhancement of the standard requirements regarding to passengers safety. Such tendencies lead to increased use of advanced high strength steels (AHSS) for manufacturing of car body components which are placed in many areas within car body structure. However, the potential application of high strength steels is still limited since many issues have to be investigated related to formability and springback.There are various strategies to minimize springback by means of process parameter variation during the press stroke or by use of additional retention forces by the blank holder. These strategies were already applied successfully in the forming of high-strength steel alloys up to 600 MPa tensile strength, and have proven successfully in practice. When using these techniques for forming of more stronger steel materials (tensile strength higher than 600 MPa), results achieved and knowledge applied with respect to component accuracy are not satisfactory due to the increased tendency towards springback and twisting. For cold forming of such steel grades until now a defined and valid strategy or method that can be used for springback and twisting compensation is missing.The motivation of the research work basically stands for lack of such methodology to reduce springback and torsion observed in load carrying components of passenger cars, as well as to find a sophisticating compensation strategy for manufacturing such steel grades. The methodology for springback compensation will be dependent on local stress-strain state as well as on magnitude of sidewall curl and torsion moment of the component. The method to be developed first will be based on optimization of binder shapes, on global and/or local application of hardening functions, on special indentations in identified areas of component as well as on details in shape for counter striking objectives of component radii.

如今，汽车行业面临着不断增加的环境法规以及不断提高的乘客安全标准要求的挑战。这种趋势导致先进高强度钢（AHSS）的使用增加，用于制造车身部件，这些部件放置在车身结构的许多区域。然而，由于许多与成形性和回弹有关的问题需要研究，高强度钢的潜在应用仍然有限。有各种各样的策略，以减少回弹的手段，在冲程过程中工艺参数的变化或通过使用额外的保持力的压边。这些策略已经成功地应用于高达600 MPa抗拉强度的高强度钢合金的成形，并在实践中得到了成功的证明。当使用这些技术来形成更强的钢材料（抗拉强度高于600mpa）时，由于回弹和扭转的趋势增加，所获得的结果和应用的知识在组件精度方面并不令人满意。对于这类钢种的冷成形，到目前为止还没有一种明确有效的策略或方法来补偿回弹和扭转。研究工作的动机基本上是缺乏这样的方法来减少乘用车承载部件的回弹和扭转，以及寻找一种复杂的补偿策略来制造这种钢种。回弹补偿的方法将取决于局部应力-应变状态以及组件的侧壁旋度和扭转力矩的大小。首先开发的方法将基于粘结剂形状的优化，整体和/或局部硬化功能的应用，部件识别区域的特殊压痕以及部件半径反冲击目标的形状细节。