Investigation of Springback of High Manganese TWIP-Steels Using Three-Point-Bending
High manganese steels (HMnS) exhibit an excellent combination of properties,such as a high yield strength as well as ultimate tensile strength and ductility at the same time,to qualify for applications in light weight automotive body parts and especially for safety relevant parts.However,it is a common problem that parts made of high strength steels exhibit large springback after sheet metal forming due to elastic recovery.This is caused by the combination of a high yield strength with a low elastic modulus that introduces high reversible elastic strain during cold forming.Beside the elastic deformation also the twinning of austenitic HMnS may have influence on the amount of springback as it causes additional residual stresses in the material during forming.Therefore,the understanding of springback mechanism is an essential requirement for the industrial use of HMnS in near net shape sheet metal forming processes.In this paper the influence of different alloying elements for HMnS onthe elasticmaterial properties and the resulting effect on springback behavior is analyzed.For this purpose different HMnS grades with varying carbon,manganese and aluminum content are investigated.A three point bending experiment is used to bend V-profiles of 1 mm thick sheet samples and the angle within the V-profile is measured after unloading.For the determination of the angle during maximum stroke a finite element simulation is used.The springback angles of the different HMnSgrades are compared and discussed in relation to their specific yield strength determined in tensile tests.The elastic recovery of HMnS shows anconsiderable influence of the alloy design,which is visible in the varying springback angles in three-point-bending experiments.
springback high manganese steel three-point-bending mechanical properties
QUADFASEL Angela LOHMAR Johannes HIRT Gerhard
Institute for Metal Forming, RWTH Aachen, 52072 Aachen,Germany
国际会议
成都
英文
221-224
2016-11-16（万方平台首次上网日期，不代表论文的发表时间）