Fracture morphologies of a hot stamped steel and comparisons with several sheet metals
Fracture morphologies of a hot stamped steel and comparisons with several sheet metals作者机构:Department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China Institute of Chemical Material China Academy of Engineering Physics Mianyang 621900 Sichuan China Department of Civil and Environmental Engineering Northwestern University Evanston 60208 Illinois USA
出 版 物:《Journal of Iron and Steel Research International》 (Journal of Iron and Steel Research, International)
年 卷 期:2017年第24卷第6期
页 面:634-640页
核心收录:
学科分类:080503[工学-材料加工工程] 08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程(可授工学、理学学位)] 0802[工学-机械工程] 080201[工学-机械制造及其自动化]
基 金:National Natural Science Foundation of China(Nos.51105247and U1564203)
主 题:Hot stamped steelFracture morphologyTensile testMechanical trimming testSteel comparison
摘 要:Hot stamping has been widely used in car industry to produce safety components. Most existing re- searches focused on the stamping and quenching process, but less on the mechanical properties of stamped parts. The fracture behaviors of hot stamped boron steel B1500HS have been studied, and other four commonly used sheet metals with different strengths, including Q235, TRIP780, QP980 and MS1300, were also introduced for comparison. Both uniaxial tests and mechanical trimming tests were performed, and the fracture surfaces under different stress states were observed and discussed. The SEM observations showed that the fracture models are closely related to the stress states, i. e., the tensile surfaces have ductile rupture characters while the trimming surfaces have brittle rupture characters. Compared with other steels, the quenched boron steel has smaller dimple size accompa- nied by shear planes in the tensile surface, and has smaller burnish zone in the trimming surface, and its cutting surface with 'S' like shape is also very different with others. Furthermore, two fitted em pirical models were derived to describe the quantitative correlations between the average dimple diam- eter and the steel strength and between the percentage of burnish zone and the steel strength.