三层钢铝异种板料无铆冲压接头质量的仿真研究

发布时间：2018-07-25 19:31

【摘要】：轻质材料的使用是当今汽车产业快速发展和实现汽车轻量化的重要手段,现代汽车车身大部分采用多材料车身,尤其是钢铝混合车身,因此钢铝混合车身结构已成为汽车轻量化研究的主要方向之一。无铆冲压连接是一种新型机械连接技术,可以有效实现异种板料的连接。而且现在车身中很多部位采用三层或更多层板材连接的形式,研究三层板无铆冲压连接有着很重要的实用价值。本文首先选取普通SPCC钢板作为研究对象,基于DEFORM分析三层钢板无铆冲压的连接过程以及影响接头质量的因素,结果表明随着位移的增加冲头的载荷逐渐增大,而且凹模受到的载荷比冲头和压边圈的都大;连接过程中板料颈部最先发生应力应变而且颈部的应力应变最大;影响三层钢板无铆冲压接头质量的因素为颈部厚度t_N1、t_N2,嵌入量t_U1、t_U2,底部厚度X。其次,选用A16061-T6代替SPCC来探讨钢铝板料不同组合方式对接头质量的影响并研究不同组合方式下接头的失效情况,结果表明铝、钢、钢组合时,铝板放中间时接头质量最好;铝、铝、钢组合时,钢板放在最下层时接头质量最好,但板料间的颈部厚度较小,需要重新调整板料的厚度;钢铝钢组合的接头承受的失效载荷最大,铝代钢后可以有效实现车身轻量化。然后,选取冲头半径、凹模深度、凹槽深度和凹槽宽度为模具参数变量,研究不同的模具参数对钢铝异种板料接头颈部厚度和嵌入量的影响,结果表明不同的模具参数对接头质量的影响各不相同,模具参数选择不当会出现很多缺陷,比如凹槽没有被完全充满、板料出现过冲压现象或者板料之间存在间隙等。最后,以凹模深度、凹槽深度、凹槽宽度和冲头半径四个因素作为试验因子,以接头的最大失效载荷作为响应,通过中心复合设计对模具参数进行多目标优化,结合有限元模拟对试验结果进行方差分析和回归分析,研究各个因子以及因子之间的交互作用对接头强度的影响规律,并且提供了各因子对接头强度影响的可视化模型,最终得出最佳试验条件下模具参数的最优组合。
[Abstract]:The use of lightweight materials is an important means for the rapid development of automobile industry and the realization of automotive lightweight. Most of the modern automobile body uses multi-material body, especially the steel-aluminum hybrid body. Therefore, the steel-aluminum hybrid body structure has become one of the main research directions of automobile lightweight. Non-riveting punching connection is a new type of mechanical connection technology, which can effectively realize the connection of dissimilar sheet metal. Now many parts of the body are connected by three or more layers of plates, so it is of great practical value to study the joint of three layers without riveting and stamping. In this paper, the common SPCC steel plate is selected as the research object. The connection process of the three-layer steel plate without riveting and the factors affecting the joint quality are analyzed based on DEFORM. The results show that the load of punch increases gradually with the increase of displacement. Moreover, the load of die is larger than that of punch and blank holder, and the stress and strain in the neck of sheet metal is the first and the strain is the largest in the neck of sheet metal. The factors affecting the quality of non-riveting joint of three-layer steel plate are neck thickness T _ S _ 1 / T _ T _ 2, intercalation quantity t _ (U _ 1) T _ (1) T _ (2), bottom thickness X _ (2). Secondly, A16061-T6 is used instead of SPCC to discuss the influence of different combination ways of steel and aluminum sheet on joint quality and to study the failure of joint under different combination modes. The results show that when aluminum and steel are combined, the quality of joint is the best when aluminum plate is placed in the middle. When aluminum and steel are combined, the quality of the joint is the best when the steel plate is placed at the lowest layer, but the thickness of the neck between the sheets is small, and the thickness of the sheet metal needs to be readjusted; the joint of the combination of steel, aluminum and steel bears the greatest failure load, After the aluminum substitute steel can realize the body lightweight effectively. Then, die radius, die depth, groove depth and groove width are selected as die parameter variables to study the influence of different die parameters on neck thickness and embedding amount of dissimilar sheet metal joint. The results show that the influence of different die parameters on the joint quality is different. The improper selection of die parameters will lead to a lot of defects, such as the groove is not completely filled, the sheet metal has stamping phenomenon or there is a gap between the sheet metal and so on. Finally, four factors such as die depth, groove width and punch radius are taken as test factors, and the maximum failure load of the joint is taken as the response. The multi-objective optimization of die parameters is carried out through the central composite design. The variance analysis and regression analysis of the test results are carried out with finite element simulation to study the influence of each factor and the interaction between the factors on the joint strength, and a visual model of the influence of each factor on the joint strength is provided. Finally, the optimal combination of die parameters under the best test conditions is obtained.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG386

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