重力加载对厚板件热成形性能的影响  

Effect of gravity loading on hot forming properties of thick sheet parts

作　　者：朱明新[1] 周海龙 尚凯 杨兴园 周鹏 张亚岐 ZHU Ming-xin;ZHOU Hai-long;SHANG Kai;YANG Xing-yuan;ZHOU Peng;ZHANG Ya-qi(School of Mechanical Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Technology Center,Dongfeng Motor Corporation,Wuhan 430058,China)

机构地区：[1]内蒙古工业大学机械工程学院,内蒙古呼和浩特010051 [2]东风汽车集团有限公司技术中心,湖北武汉430058

出　　处：《塑性工程学报》2020年第1期46-51,共6页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(61374196; 51178053);教育部长江学者和创新团队发展计划项目(IRT1286)

摘　　要：以军车厚板件为例,分析重力加载对热冲压结果的影响。首先分析薄、厚板热冲压成形性差异,通过分析板料载荷中心沿y向的位移量,给出了重力影响程度与厚板零件对称性之间的关系,零件自对称部分受力是均匀的,料片y向偏移量很小;其次,在Dynaform中构建分析模型,对比分析重力加载对厚度应变、马氏体含量、减薄率以及温度变化率的影响;最后,试制样件,并与有限元分析结果进行对比,结果表明:有重力加载时分析结果与实际测量值更为接近,且重力加载对沿板料长度方向对称的厚板件影响较小,对非对称件影响较大;重力对厚板件减薄率(厚度方向应变变化)的影响占到9%;重力加载对腹面马氏体含量影响较大,对翼面马氏体含量影响很小。The thick sheet metal parts for military vehicles was taken as an example to study the effect of gravity loading on the hot forming results. Firstly,the difference of hot stamping formability between thin and thick sheets was analyzed. By analyzing the displacement of sheet loading center along y direction,the relation between the influence degree of gravity and the symmetry of thick parts was given.The force on the self-symmetrical parts is uniform,and the y direction deviation of the sheet is very small. Secondly,the analysis model was built in Dynaform to compare and analyze the influence of gravity loading on thickness strain,martensite content,thinning rate and temperature variation rate. Finally,the product was trialed and compared with the finite element analysis results. The results show that the analysis results with gravity loading is closer to the actual measured value,and the gravity loading has little effect on the symmetrical thick sheet part along the length of the sheet,but has more effect on the asymmetric one. The effect of gravity on the thinning ratio( the change of strain along thickness direction) of thick sheet parts accounts for 9%. Gravity loading has a great effect on the content of ventral martensite and little effect on the content of wing martensite.

关 键 词：厚板件 重力加载 热成形 厚度方向应变 

分 类 号：TG386[金属学及工艺—金属压力加工]