铝锂合金薄板微结构辊压微成形缺陷及其电致塑性效应数值模拟研究  

Numerical Simulation on Electrically-assisted Roll Micro-forming Defects of Micro-structures and Electroplastic Effects on Al-Li Alloy Sheets

作　　者：汪鑫伟[1,2] 高鹏永 石胜龙 刘琛[1] 徐杰[2] 王春举 李建伟 郭斌[1,2] 单德彬[2] WANG Xin-wei;GAO Peng-yong;SHI Sheng-long;LIU Chen;XU Jie;WANG Chun-ju;LI Jian-wei;GUO Bin;SHAN De-bin(Laboratory for Space Environment and Physical Sciences,Ministry of Education,Harbin Institute of Technology,Harbin 150001,China;Key Laboratory of Micro-Systems and Micro-Structures Manufacturing,Ministry of Education,Harbin Institute of Technology,Harbin 150001,China;School of Mechanical and Electrical Engineering,Soochow University,Jiangsu Suzhou 215131,China;Beijing Hangxing Machinery Manufacture Limited Corporation,Beijing 100013,China)

机构地区：[1]哈尔滨工业大学空间环境与物质科学研究院,哈尔滨150001 [2]哈尔滨工业大学微系统与微结构制造教育部重点实验室,哈尔滨150001 [3]苏州大学机电工程学院,江苏苏州215131 [4]北京航星机器制造有限公司,北京100013

出　　处：《精密成形工程》2023年第10期82-94,共13页Journal of Netshape Forming Engineering

基　　金：黑龙江省自然科学基金优秀青年项目(YQ2020E014)。

摘　　要：目的研究微结构形状及尺寸、压下量、温度、电流强度和电流路径对电流辅助辊压成形的影响规律,分析辊压过程中多物理场耦合行为,探究电致塑性效应对辊压成形的作用机理,并以此来解决薄板微结构形性协同控制关键问题。方法采用ABAQUS建立微结构辊压有限元模型,通过辊压成形数值模拟方法进行相关研究。首先设计了三因素三水平正交试验,探究了沟槽形状、沟槽深度、压下量对成形效果的影响。其次通过改变电流大小、对比辊对辊(R2R)和辊对板(R2P)2种电流路径、对比电流辅助辊压和等温辊压模拟试验来依次探究电流强度、电流路径、电流的非热效应对铝锂合金薄板微结构辊压成形过程中微结构填充率与板材翘曲高度等辊压成形缺陷的影响规律。结果在R2R电流路径下,电流分布于整个板厚空间,而在R2P电流路径下,电流主要分布于材料表面,2种路径下的温度与应力分布相似,但R2R下的峰值温度略高,约高20℃;峰值应力略小,约小35MPa。当压下量与微沟槽宽度越大、沟槽形状越接近矩形时,辊压填充高度和翘曲高度均越大。在相同温度下,与等温辊压相比,电流辅助辊压微结构填充高度更高。三角形微沟槽在100 A、30%压下量时的辊压填充高度提升率高达7%。在等温辊压下,微结构填充时的塑性流动主要分布于表层;而在电流辊压下,微结构填充时的塑性流动在整个板厚范围内分布得较为均匀,且应力集中不明显。温度对辊压微结构薄板翘曲程度的改善作用较小,电致塑性效应大幅改善了微结构薄板辊压翘曲程度,翘曲高度减小约70%。结论从焦耳热均匀性角度来看,电流路径选择R2R更优。通过改变压下量、微沟槽宽度与形状可以改变微结构辊压成形效果。相较于等温辊压,电流辅助辊压可以提高辊压填充高度、减小板材翘曲高度,故其成形效果更好,说明电�The work aims to study the effect of microstructure shape and size,reduction,temperature,current intensity and current path on electrically-assisted roll forming,analyze the coupling behavior of multiple physical fields in the roll forming process,and clarify the mechanism of electroplastic effect in roll forming,so as to solve the key problem of the synergistic con-trol of the accuracy and property of micro-structures on sheets.ABAQUS was used to establish a finite element model,and the related research was carried out by numerical simulation of roll forming.Firstly,an orthogonal experiment with three factors and three levels was designed to explore the effect of groove shape,groove depth and reduction on forming.Then,the effect of cur-rent intensity,current path and non-thermal effect on microstructure rolling defects of Al-Li alloy sheet such as microstructure filling rate and sheet warping height was explored,by changing the magnitude of current,comparing roll-to-roll(R2R)connec-tion and roll-to-plate(R2P)connection,and comparing electrically-assisted and isothermal roll forming simulation tests.The current density for the R2R was distributed across the whole thickness of the sheet,while it tended to be distributed on the sur-face in the R2P.The distributions of temperature and stress for the two connection modes were similar,but compared with R2P,R2R had a slightly higher peak temperature of about 20℃and a slightly lower peak stress of about 35 MPa.When the roll forming reduction and the width of micro-groove were larger,and the groove shape was closer to rectangle,the groove filling height and the sheet warping height were larger.The filling height of microstructure by electrically-assisted roll forming at the same temperature was higher than that by isothermal case,and the filling height of triangular microgrooves could be increased by up to 7%at 100 A and 30%reduction.The plastic flow tended to be located at the surface layer in the isothermal roll forming of micro-structures,while the microstructure fi

关 键 词：铝锂合金 电流辅助 成形缺陷 微结构 电致塑性效应 

分 类 号：TG335.55[金属学及工艺—金属压力加工]