材料参数对超塑性恒压充模胀形过程影响的数值分析

NUMERICAL ANALYSIS OF THE EFFECTS OF MATERIAL PARAMETERS ON SUPERPLASTIC DIE BULGING PROCESS UNDER CONSTANT PRESSURE

采用大变形刚粘塑性有限元法模拟了超塑性恒压充模胀形过程，分析了应变速率敏感性指数ｍ、应变硬化指数ｎ和厚向异性指数Ｒ等材料参数对胀形件厚度分布、成形时间、等效应变场及胀形成形能力的影响；

The superplastic die bulging process under constant pressure is simulated by using large deformation rigid visco plastic finite element method(FEM).The effects of material parameters,such as the strain rate sensitive index m ,the strain hardening index n ,and the normal anisotropy index R , on some aspects in the bulging process,which include the thickness distribution of the workpiece,the forming time,the effective strain field,and the deformation ability of the material,are analysed and discussed comprehensively.Corresponding experiments are performed on aluminum alloy LY12CZ and good agreement is found between the numerical and experimental results.