板材充液拉深条件下壳单元与实体单元失稳起皱行为研究  

Study on buckling and wrinkling behavior of shell and solid elements under hydro-mechanical deep drawing of sheet metal

作　　者：沈伟财 张志超 胡蓝 郭立杰 张稳 庄新村 赵震 SHEN Wei-cai;ZHANG Zhi-chao;HU Lan;GUO Li-jie;ZHANG Wen;ZHUANG Xin-cun;ZHAO Zhen(Institute of Forming Technology&Equipment,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;Shanghai Aerospace Equipments Manufacture Co.,Ltd.,Shanghai 200245,China)

机构地区：[1]上海交通大学材料科学与工程学院塑性成形技术与装备研究院,上海200030 [2]上海航天设备制造总厂有限公司,上海200245

出　　处：《塑性工程学报》2025年第2期1-9,共9页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(52375352);中国航天科技集团公司第八研究院产学研合作基金资助项目(USCAST2021-20);上海市青年科技启明星计划项目(21QB1402100);上海市优秀学术带头人计划项目(21XD1431800)。

摘　　要：以贮箱整底用2219铝合金板材为研究对象,根据实际充液拉深成形过程,开展了充液拉深成形仿真模拟。为探究仿真中不同单元类型对起皱预测的影响,设计并开展了长杆压缩实验,并利用实体单元以及具有不同参考面选择的壳单元进行有限元仿真,分析了不同单元类型下试样的失稳特性。对比实验和仿真结果发现,与实体单元相比,壳单元参考面的选择影响单元厚度方向求解域的连续性,严重失稳情况下单元厚度方向求解域可能发生重叠或缺失,进而造成计算结果偏差较大,并且壳单元忽略薄板沿厚度方向的应力,对失稳的几何响应比实体单元更加敏感。在充液拉深仿真中,零件最终起皱情况对充液压力施加初期零件表面初始几何起皱较为敏感,当零件表面具有一定的初始起皱时,均匀分布的法向充液压力会在失稳起皱区域处形成平衡,并在后续变形过程中演化成更严重的起皱缺陷。Taking the 2219 aluminum alloy sheet metal used for tank bottoms as the research object,hydro-mechanical deep drawing simulation was conducted based on the actual hydro-mechanical deep drawing process.To study the influence of different element types on wrinkling prediction,the long rod compression experiments were designed and conducted.The finite element simulation was conducted using solid elements and shell elements with different reference surfaces to analyze the buckling characteristics under different types of elements.The comparison between experiment and simulation results shows that compared with solid elements,the selection of reference surfaces in the shell element affects the continuity of the solution domain in the element thickness direction.In the case of serious buckling,the solution domain on the element thickness direction might overlap or be missing,resulting in large deviation in calculation result.In addition,the shell element ignores the stress along the thickness direction of thin sheet and is more sensitive to the geometric response of buckling than that of the solid element.In the simulation of hydro-mechanical deep drawing,the wrinkling of the final part is sensitive to the initial geometric buckling of the part surface at the early stage of applying hydro-mechanical pressure.When there is certain initial wrinkling on the surface of the part,the uniformly distributed normal hydraulic pressure can be balanced at the buckling and wrinkling area,leading to more serious wrinkling defects in the subsequent deformation process.

关 键 词：起皱 有限元模拟 实体单元 壳单元 充液拉深成形 

分 类 号：TG376[金属学及工艺—金属压力加工]