边部冲裁对双相钢拉伸性能影响的实验研究  

Experimental Investigation of the Influence of Sheared Edge on Tensile Properties of Dual Phase Steel

作　　者：郑欢[1] 吴彦骏[2,3] 刁可山[2,3] 庄新村[1] 陈劼实[1] 赵震[1] 

机构地区：[1]上海交通大学塑性成形技术与装备研究院,上海200030 [2]宝山钢铁股份有限公司研究院,上海201900 [3]汽车用钢开发与应用技术国家重点实验室(宝钢),上海201900

出　　处：《上海交通大学学报》2014年第3期405-411,共7页Journal of Shanghai Jiaotong University

基　　金：国家自然科学基金资助项目(51105250;51105246)

摘　　要：为研究边部冲裁对双相钢(DP590、DP780和DP980)拉伸性能的影响,采用冲裁和线切割2种方法制备实验试样.基于MTS793材料试验机,使用非接触式视频应变测量方法,在常温下完成静拉伸实验.通过材料的力学性能曲线,分析原始标距对拉伸性能的影响以及不同断面质量下拉伸试样的力学性能响应、颈缩过程与断口形貌.结果表明:原始标距减小,基本不影响屈服强度、抗拉强度和最大力非比例伸长率,而断裂总伸长率显著增大;冲裁试样与线切割试样在拉伸颈缩段存在较大差别,断裂总伸长率低于线切割试样,且随着冲裁间隙的增大而减小;DP590和DP780冲裁试样在非均匀颈缩和横向裂纹出现后,呈现折线状断口,而DP980冲裁试样则与线切割试样的剪切滑移型断口类似,颈缩时产生显著的剪切带.To study th pared by blanking and e tensile properties of dual phase （DP） steels after blanking, specimens were prewire-electrode cutting, and static tensile tests of specimens made of DP590, DP780 and DP980 were performed by utilizing non contact video gauge at MTS793 material testing machine. The influence of gauge length on tensile behaviors and properties, and the necking phase and fracture appearance of specimens with different blanking clearances through tensile curves were analyzed. The result shows that with the decrease of gauge length, the 0.2% proof strength Rp0.2, the tensile strength R and the percentage elongation at maximum force Agt remain unchanged but the percentage total elongation at fracture A, increases notably. There is a clear difference between blanking and wire-electrode cutting specimen in tensile fracture curves. The A, of blanking specimens is lower than that of the wire electrode cutting specimen and decreases with the rise of blanking clearance. Blanking specimens of DP590 and DP780 were fractured in polygonal line after nonuniform necking and transverse cracks, while DP980 is similar to the shear shape of wire-electrode culting specimens with apparent shear bands during necking.

关 键 词：双相钢 冲裁 拉伸 原始标距 颈缩 

分 类 号：TG386[金属学及工艺—金属压力加工]