A New Ductile Fracture Criterion for Various Deformation Conditions Based on Microvoid Model  

作　　者：HUANG Jian-ke DONG Xiang-huai 

机构地区：[1]National Die and Mould CAD Engineering Research Center, Shanghai Jiao Tong University, Shanghai 200030, China

出　　处：《Journal of Iron and Steel Research International》2009年第5期92-97,86,共7页

基　　金：sponsored by National Natural Science Foundation of China(50575143);Research Fund for the Doctoral Program of Higher Education(20040248005)

摘　　要：To accurately predict the occurrence of ductile fracture in metal forming processes, the Gurson-Tvergaard （GT） porous material model with optimized adjustment parameters is adopted to analyze the macroscopic stressstrain response, and a practical void nucleation law is proposed with a few material constants for engineering applications. Mechanical and metallographic analyses of uniaxial tension, torsion and upsetting experiments are performed. According to the character of the metal forming processes, the basic mechanisms of ductile fracture are divided into two modes： tension-type mode and shear-type mode. A unified fracture criterion is proposed for wide applicable range, and the comparison of experimental results with numerical analysis results confirms the validity of the newly proposed ductile fracture criterion based on the GT porous material model.To accurately predict the occurrence of ductile fracture in metal forming processes, the Gurson-Tvergaard （GT） porous material model with optimized adjustment parameters is adopted to analyze the macroscopic stressstrain response, and a practical void nucleation law is proposed with a few material constants for engineering applications. Mechanical and metallographic analyses of uniaxial tension, torsion and upsetting experiments are performed. According to the character of the metal forming processes, the basic mechanisms of ductile fracture are divided into two modes： tension-type mode and shear-type mode. A unified fracture criterion is proposed for wide applicable range, and the comparison of experimental results with numerical analysis results confirms the validity of the newly proposed ductile fracture criterion based on the GT porous material model.

关 键 词：ductile fracture metal forming process void nucleation mechanical analysis metallographic analysis 

分 类 号：TG115.57[金属学及工艺—物理冶金] TQ534[金属学及工艺—金属学]