金属材料宽应变率下动态本构模型及其扩展有限元应用  

Dynamic constitutive model of metals at wide strain rates and its extended finite element implementation

作　　者：李双蓓[1,2] 吴园 赵璇 彭林欣 LI Shuang-bei;WU Yuan;ZHAO Xuan;PENG Lin-xin(School of Civil Engineering and Architecture, Guangxi University, Nanning 530004, China;Key Laboratory of Disaster Prevention and Structural Safety of China Ministry of Education, Nanning 530004, China;Key Laboratory of Disaster Prevention and Engineering Safety of Guangxi, Nanning 530004, China)

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004 [2]工程防灾与结构安全教育部重点实验室,广西南宁530004 [3]广西防灾减灾与工程安全重点实验室,广西南宁530004

出　　处：《广西大学学报（自然科学版）》2021年第4期905-916,共12页Journal of Guangxi University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(11562001);广西科技重大专项(桂科AA18118029);广西重点实验室系统性研究项目(2014ZDX02);广西研究生教育创新项目(YCSW2018047)。

摘　　要：为了准确描述金属材料在各类动荷载下的力学行为,基于金属流变应力在不同应变率范围内的不同函数表现形式,采用开关函数反映金属宽应变率强化效应差异,考虑应变硬化效应与绝热温升影响相互耦合,结合多种金属材料在不同应变率下的试验数据进行拟合分析,发展了一种动态本构统一方程JC-CS模型。通过UMAT用户子程序,将新模型导入ABAQUS有限元分析软件中预测不同应变率下的金属动态应力应变关系,并基于此进行动态正弦荷载下的金属裂纹扩展分析。研究结果表明,新构建模型的数值模拟本构曲线与试验数据吻合良好,且能结合扩展有限元在ABAQUS动态隐式环境中使用,为准确描述金属在动荷载作用下的力学行为提供了一种工程应用分析模型。The purpose of this research is to accurately describe the mechanical behaviors of metal materials under various dynamic loads.Based on the different functional expressions of the metal flow stress over different strain rate ranges,a switch function is used to reflect the difference in the wide strain rate strengthening of the metal.By considering the coupling between the strain hardening effect and adiabatic temperature rise,and analyzing the experimental data of multiple metals materials in different strain rates,a dynamic constitutive unified equation JC-CS model is developed.Through the UMAT subroutine,the new model is imported into the finite element analysis software ABAQUS to predict the dynamic stress-strain relationship of metals with different strain rates.And a metal crack propagation analysis under dynamic sinusoidal loads is conducted.The research results show that the numerical constitutive curve of the proposed model is in good agreement with the experimental data,and can be used in the ABAQUS dynamic implicit environment in combination with the extended finite elements.The proposed model can accurately describe the mechanical behaviors of metals under dynamic loads,and provides an practical model for engineering feasibility.

关 键 词：动态本构模型 宽应变率 JC-CS模型 UMAT子程序 扩展有限元 

分 类 号：O344[理学—固体力学]