预应变超薄不锈钢板材弯曲回弹  

Springback of pre-strain ultrathin stainless steel sheet

作　　者：张睿[1] 邓宇君[1] 易培云[1] 彭林法[1] ZHANG Rui;DENG Yu-jun;YI Pei-yun;PENG Lin-fa(Shanghai Key Laboratory of Digital Manufacture for Thin-walled Structures,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学上海市复杂薄板结构数字化制造重点实验室

出　　处：《塑性工程学报》2018年第6期14-20,共7页Journal of Plasticity Engineering

基　　金：国家重点研发计划项目(2017YFB0103001)

摘　　要：针对不同晶粒尺寸的超薄316L不锈钢板材试样,开展了不同预应变材料的拉伸实验和弯曲实验,研究材料在多次拉伸中的力学行为,探索预应变对弯曲回弹的影响。研究表明流动应力和回弹角都随晶粒尺寸增大而降低,多次拉伸中预应变对材料拉伸应力应变关系没有显著影响,但预应变使材料发生加工硬化导致了回弹角随预应变增加而增大。进一步的实验结果与数值模型计算结果对比表明,预应变对材料压缩力学行为的影响是导致回弹角预测偏大的主要原因。The ultrathin 316 L stainless sheet samples with different grain sizes were prepared. The tensile and bending experiments were conducted on different pre-strain samples to study both the mechanical behavior in multi-stage tensile and the influence of pre-strain on springback behavior after bending. The study shows that both the flow stress and springback angle decrease with the increase of the grain size,the pre-strain has no significant effect on the tensile stress-strain relation of the material in repeated tensile. However,the pre-strain causes hardening of the material,so the springback angle increases with the increase of the pre-strain. The comparison between further experimental result and the mathematical calculation result indicates that the effect of the pre-strain on the compressive mechanical behavior of materials is the main reason for the overestimation prediction of the springback angle.

关 键 词：薄板成形 预应变 不锈钢 回弹 

分 类 号：TG306[金属学及工艺—金属压力加工]