东风某SUV全景天窗制造缺陷分析及对策(含CAD图,CATIA三维图)

东风某SUV全景天窗制造缺陷分析及对策(含CAD图,CATIA三维图)(任务书,开题报告,外文翻译,论文计算书10000字,CAD图5张,CATIA三维图)
摘  要
在汽车制造过程当中，对大尺寸的车身覆盖件，往往是采取冲压成形的工艺方法进行加工；但是冲压成形过程当中板料的不均匀塑性变形常引发制件上不均匀分布的残余应力应变。残余应力的存在不但会影响制件的形状精度和力学性能，严重者甚至导致零件出现破裂、塌陷等缺陷。本文以实际生产中出现塌陷问题的某SUV全景天窗顶盖外板为研究对象，利用AutoForm软件进行拉延、修边、冲孔等冲压工艺的有限元模拟，分析了不同冲压变量下制件的残余应力应变分布规律，结果表明板料冲压成形后得残余应力应变分布情况取决于材料属性、压边力、模具几何结构等多种因素。顶盖外板拉延成形后的材料不均匀塑性变形引起的残余应力，经修边冲孔、卸载回弹等工序后得到释放并重新分布，是引起制件出现塌陷的本质原因。较大的硬化指数可以减小冲压成形后制件的塌陷深度，而大的厚向异性系数以及小屈强比的板料不容易出现起皱、破裂等冲压缺陷问题，增大压边力会使得冲压成形后的残余应力应变较小，导从而减小冲压后制件的塌陷深度，适当减小凹模圆角半径可以促进板料的弹性变形转换为塑性变形，从而使板料成形后制件更稳定，降低卸载后的残余应力大小。

[来源：http://www.doc163.com]

关键词：塌陷 冲压 残余应力 有限元网格映射算法

Abstract
In the automotive manufacturing process, the large-size body panels are often processed by a stamping process; however, the uneven plastic deformation of the sheets during the press forming process often causes uneven distribution of residual stress strain on the workpiece. The existence of residual stress will not only affect the shape accuracy and mechanical properties of the parts, but also lead to cracks, collapses, and other defects in the parts. This article takes the SUV panoramic sunroof roof cover with the subsidence problem in actual production as the research object, uses AutoForm software to carry out the finite element simulation of drawing, trimming, punching and other stamping processes, and analyzes the different parts under different stamping variables. The distribution of residual stress and strain shows that the residual stress and strain distribution after sheet metal forming depends on many factors such as material properties, blank holder force, and mold geometry. The residual stress caused by the non-uniform plastic deformation of the formed material after drawing the outer plate of the top cover is released and redistributed after trimming, punching, unloading, and rebound, which is the essential cause of the collapse of the part. A larger hardening index can reduce the collapse depth of the stamped part, while the large anisotropy coefficient and the small yield ratio of the sheet material are not prone to wrinkle, crack, etc. stamping defects, increasing the blank holder force. Making the residual stress and strain after punching forming smaller, leading to reduce the collapse of the workpiece after the depth of the depression, appropriate to reduce the corner radius of the die can promote the elastic deformation of the sheet material into plastic deformation, so that the sheet metal after forming The pieces are more stable and reduce the residual stress after unloading. [资料来源：http://Doc163.com]
Key Words：Collapse  Stamping  Residual Stress  Finite element mesh mapping algorithm

 

目  录
第1章 绪论    1
1.1 研究背景与意义    1
1.1.1 研究背景    1
1.1.2 研究目的及意义    1
1.2 国内外研究现状    2
1.2.1 冲压残余应力的研究    2 [资料来源：http://Doc163.com]
1.2.2 研究现状评述    3
1.3 研究内容及研究方法    3
1.3.1 研究内容    3
1.3.2 技术路线    4
第2章 有限元建模    5
2.1 引言    5
2.2 顶盖外板有限元模型分析    5
2.2.1 CATIA软件介绍    5
2.2.2 顶盖外板工艺分析及有限元模型    5
2.3 冲压有限元建模    6
2.3.1 凹模、凸模及压边圈的几何模型    6
2.3.2 冲压有限元模型    7
2.4 本章小结    8
第3章 冲压残余应力分布规律    9
3.1 引言    9
3.2 冲压有限元模拟    9
3.2.1 AutoForm软件介绍    9
3.2.2材料    9
3.2.3边界条件    10
3.3冲压成形后残余应力分布情况    11
3.3.1评价指标    11
3.3.2冲压件残余应力分布规律    11

[资料来源：http://Doc163.com]

3.4 本章小结    11
第4章 冲压残余应力影响规律    12
4.1 引言    12
4.2 冲压残余应力应变影响规律    12
4.2.1 材料属性对冲压残余应力的影响    12
4.2.2 压边力对冲压残余应力的影响    12
4.2.3 模具几何结构对冲压残余应力的影响    13
4.3 本章小结    14
第5章 总结    15
5.1 研究结论    15
5.2 对策分析    15
5.3 研究展望    16
参考文献    17
致谢    19