轧制差厚板单向拉伸性能研究

Research on uniaxial tension performance of tailor rolled blank

分别采用解析、仿真以及试验方法对轧制差厚板(tailor rolled blank,TRB)的单向拉伸性能进行研究.基于金属塑性变形理论,推导了轧制差厚板单向拉伸的力学解析模型,对未退火和已退火的1.2、2.0mm等厚板及1.2/2.0mm轧制差厚板进行单向拉伸试验,并从金相组织上解释了退火前后轧制差厚板的性能差异.最后在拉伸试验的基础上,对未退火和已退火的1.2/2.0mm轧制差厚板进行单向拉伸仿真.结果表明:解析模型能够准确地描述轧制差厚板单向拉伸过程中的应力应变状态,未退火和已退火轧制差厚板单向拉伸试样的缩颈均发生在试样薄侧,并且退火后的轧制差厚板表现出更好的成形性能,解析、仿真以及试验结果能够较好地吻合.

Uniaxial tension performance of tailor rolled blank （TRB） is studied by means of analytical, simulated and experimental methods, respectively. The analytic model of TRB for uniaxial tension is derived from theory of metal plastic deformation. Uniaxial tension experiments on unannealed and annealed 1.2 mm and 2.0 mm uniform blanks as well as 1.2/2.0 mm TRB are carried out, and the difference in the performance of TRB before and after annealing is explained by metallurgical structure. Then, uniaxial tension processes of unannealed and annealed 1. 2/2.0 mm TRBs are simulated on the basis of uniaxial tension experiments. The experimental results indicate that the stress-strain state of TRB during uniaxial tension can be accurately represented by the analytic model. The necking of unannealed and annealed TRB specimens for uniaxial tension both happens at the thinner sides, and the annealed TRB shows better formability. The conclusions drawn by analytical model, simulation and experiment show good agreement.