304不锈钢薄板微塑性成形尺寸效应的研究  

Investigation of Size Effects of 304 Stainless Steel Foils in Microforming Processes

作　　者：孟庆当[1] 李河宗[2] 董湘怀[1] 彭芳[1] 王倩[1] 

机构地区：[1]上海交通大学,上海200030 [2]河北工程大学,邯郸056038

出　　处：《中国机械工程》2013年第2期280-283,共4页China Mechanical Engineering

基　　金：国家自然科学基金资助项目(50835002;50821003;50975174);高等学校博士学科点专项科研基金资助项目(20100073110044;200802480053)

摘　　要：针对五种厚度304不锈钢薄板进行了单向拉伸试验和微弯曲试验,测得的屈服应力和回弹角均随板厚减薄而增大,表现出"越薄越强"的尺寸效应现象。通过在Hall-Petch公式中引入相对厚度项对公式进行修正,使得对屈服应力的预测与试验结果更吻合。采用修正的Nix-Gao应变梯度强化模型预测了回弹角与板厚的关系,预测结果与试验结果吻合。Uniaxial tension and microbending tests were conducted using 304 stainless steel foils with varied thicknesses from 10μm to 200μm. In the tests, the yield stress and springback angle increased with decreasing foil thickness, showing the size effects of ＂the thinner the stronger＂. The Hall --Petch equation was modified by introducing the influence of foil relative thickness, and applied to calculate yield stress with better agreement with test results. The modified Nix--Gao strain gradient hardening model was used to predict the relationship between springbaek angle and foil thickness, which agree with the test results.

关 键 词：304不锈钢 屈服应力 应变梯度 回弹角 

分 类 号：TG301[金属学及工艺—金属压力加工]