基于损伤力学的金属材料韧性断裂失效分析  

Fracture Failure Analysis of Ductile Metals Based on Continuum Damage Mechanism

作　　者：苏维国[1] 穆志韬[1] 刘涛[1] 马晓乐[1] 

机构地区：[1]海军航空工程学院青岛校区,青岛266041

出　　处：《宇航材料工艺》2014年第2期24-28,共5页Aerospace Materials & Technology

基　　金：总装"十二五"预研项目(4010901030201)

摘　　要：金属韧性断裂是损伤累积的结果,以孔洞演化理论和细观损伤力学模型为基础,将韧性断裂机制分为拉伸型和剪切型两种类型,提出了一个适用于不同变形路径的统一形式的韧性断裂准则。通过编写用户材料子程序VUMAT,将韧性断裂准则嵌入到ABAQUS有限元软件的准静态算法主程序中,模拟了航空铝合金LY12CZ(Kt=1和3)单向拉伸时材料损伤累积、裂纹萌生、扩展直至韧性断裂的物理全过程,并通过拉伸试验验证了模型的有效性。韧性金属材料孔洞断裂机制研究表明,单调加载过程中宏观裂纹的形成是孔洞在夹杂物和第二相微粒周围形核、长大直至聚合的结果。Ductile fracture in metals is the accumulative result of damage. The basic mechanisms of ductile frac- ture are divided into two modes （tension-type mode and shear-type mode） according to voids evolution model and me- so-damage mechanism. A unified ductile fracture criterion is proposed for wide applicable range. The proposed ductile fracture criterion is implemented into quasi-static finite element method through a compilation of user＇ s material sub- routine VUMAT of the commercial finite element platform ABAQUS. The ductile fracture model is validated by com- paring between experimental data and numerical results. It is shown that the proposed ductile fracture model can accu- rately and effectively predict the whole damage process of ductile metals nal fracture. Ductile metallic materials voids-fracture mechanism studies monotonic in the loading process are the growth of voids in the inclusions ation polymerization. including crack initiation, propagation and fishow that the formation of macroscopic crack and second phase particles around the nucle-ation until the polymerization.

关 键 词：韧性金属材料 断裂 损伤累积 有限元分析 

分 类 号：TB386[一般工业技术—材料科学与工程]