金属韧性断裂准则的数值模拟和试验研究  

Numerical simulation and experimental verification of ductile fracture criteria of metals

作　　者：黄建科[1,2] 董湘怀[1] 

机构地区：[1]上海交通大学模具CAD国家工程研究中心,上海200030 [2]上海飞机设计研究院,上海200232

出　　处：《材料科学与工艺》2010年第4期450-454,共5页Materials Science and Technology

基　　金：国家自然科学基金资助项目(50575143);高等学校博士学科点专项科研基金资助项目(20040248005)

摘　　要：对不同外形的45钢试件进行了拉伸、压缩和扭转等材料试验,对工程中常用的5个韧性断裂准则的适用范围进行了对比研究,并采用Gurson-Tvergaard(GT)多孔材料本构模型对试验过程进行了数值模拟.指出目前使用的断裂准则都不可能对材料在多种变形条件下给出一个固定临界值.根据金属成形工艺特点,综合考虑拉伸型和剪切型2种不同韧性断裂机制,提出一个统一的韧性断裂准则形式.试验和数值计算结果证明了该准则的有效性和普适性,进而利用单向拉伸和扭转试验确定的材料常数合理地预测压缩过程中的韧性断裂现象.Tension,compression and torsion tests on 45 steel were carried out for providing the critical values at fracture,and numerical simulation of the physical experiments was performed by using Gurson-Tvergaard（GT） porous material model to compare the relative application range of 5 widely used ductile fracture criteria.The comparison reveals that it is impossible to capture all features of ductile fracture under various deformation conditions by a single criterion.A unified fracture criterion,considering both tension-type mode and shear-type mode,is proposed and applied in the analysis.Experimental and numerical results confirm the validity and wide applicability of the new ductile fracture criterion.Moreover,material constants obtained through uniaxial tension and torsion experiments are used to predict the occurrence of ductile fracture in compression process.

关 键 词：韧性断裂准则 数值模拟 金属成形过程 

分 类 号：TG306[金属学及工艺—金属压力加工] TG111