惯性效应对延性金属中微孔洞动态演化过程的影响及破坏分析  

EFFECT AND FRACTURE ANALYSIS OF INERTIA ON DYNAMIC VOID GROWTH PROCESS OF DUCTILE METALS

作　　者：刘斌[1,2] 徐绯[1] 李振[1] 

机构地区：[1]西北工业大学航空学院,西安710072 [2]西北工业大学无人机研究所,西安710072

出　　处：《机械强度》2013年第2期219-225,共7页Journal of Mechanical Strength

基　　金：教育部新世纪优秀人才支持计划(NECT080454)资助

摘　　要：利用Abaqus提供的用户材料本构接口,将Gurson模型用UMAT(user defined material subroutine)和VUMAT(vectorized user defined material subroutine)分别实现。其中UMAT适用于Abaqus中的Standard计算模块,忽略惯性效应,而VUMAT适用于Abaqus中的Explicit计算模块,包含惯性效应。通过对二者的计算结果进行对比分析,考察惯性效应对孔洞长大的作用与影响。结果表明:(1)惯性效应对加载速率非常敏感,随着加载速率的提高,惯性效应先是抑制,继而促进孔洞的长大。(2)存在一个临界应变率,在临界应变率时,惯性效应不抑制也不促进孔洞的长大,对LY12CZ铝合金,临界应变率大约在1 740 s-1。(3)从惯性效应的角度,不但可以解释高应变率下断裂应变随应变率的增加而增大的现象,而且也能解释超高应变率条件下铝合金表现出的脆性特征。The Gurson model is achieved by UMAT （user defined material subroutine） and VUMAT （vectorized user defined material subroutine） subroutines, which are the interfaces provided by Abaqus software, respectively. UMAT is used for standard calculation module in Abaqus software, ignoring inertial effect, while VUMAT for Explicit calculation module in Abaqus software, containing inertial effect. After the calculated results are analyzed comparatively, the influence of inertial effect on void growth behavior is investigated. The results show that ： （ 1 ） Inertial effect is sensitive to loading rate, with the increasing of the loading rate, inertial effect restrains void growth in the beginning, then it accelerates void growth; （2） There is a critical loading rate, at which inertial effect has no influence on void growth, for aluminum alloy LY12CZ, the critical loading rate is about 1 740 s^-1 ; （ 3 ） From the view of inertial effect, it can explain the phenomena that the fracture strain increases along with the increasing of strain rate at dynamic loading condition. Besides, it also can explain the characteristic of ＇ brittleness＇ performed by aluminum alloys at higher loading condition.

关 键 词：惯性效应 Gurson模型 用户材料子程序 临界应变率 

分 类 号：O346.5[理学—固体力学] TB115[理学—力学]