基于Gurson-JC模型的铝合金6061T6和低碳钢Q235力学性能表征  

Characterization of mechanical properties of aluminium alloy 6061T6 and low carbon steel Q235 based on Gurson-JC model

作　　者：陆善彬[1] 周璐瑶[1] 郭赛[1] 

机构地区：[1]吉林大学汽车动态仿真与控制国家重点实验室,吉林长春130025

出　　处：《合肥工业大学学报（自然科学版）》2014年第6期641-644,694,共5页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学青年基金资助项目(51105166)

摘　　要：文章对低碳钢Q235和铝合金6061T6试样在不同应力三轴度下进行拉伸试验,得到2种材料在不同工况下的力学性能。采用LS-OPT软件对Gurson模型相关参数进行优化,该优化方法既可以提高参数确定的效率,同时可以使Gurson模型在一定应力三轴度范围内适用。但Gurson模型不能准确预测在低应力三轴度下的失效,所以在低应力三轴度下引入Johnson-Cook模型的应变失效标准,以弥补剪切工况下的不足。通过比较Gurson模型和Johnson-Cook模型对2种材料在不同应力三轴度下的仿真结果,确定2种材料的Gurson-JC模型相关参数,以满足在较大范围内的应力三轴度下的仿真精准度。T he basic sheet material fracture testing under different stress triaxialities and strain rates is carried out on specimens of low carbon steel Q 235 and aluminium alloy 6061T6 ,and the mechanical properties of these two materials under different working conditions are obtained .Six parameters of Gurson model are optimized by using LS-OPT software .This optimization method improves the effi-ciency in parameters determination and makes Gurson model applicable under a certain range of stress triaxiality .However ,Gurson model is incapable of predicting shear fracture under low stress triaxiali-ty .So an improved Gurson model with the strain failure criterion of Johnson-Cook model under low stress triaxiality is used to overcome this weakness under the shear working condition .Through the simulation and comparison of two materials under different stress triaxialities and strain rates by Gur-son model and Johnson-Cook model ,the relevant parameters of Gurson-JC model of the two materials are determined so as to satisfy the accuracy requirement under a wider range of stress triaxiality and strain rate .

关 键 词：Gurson模型 Johnson-Cook模型 LS-OPT软件 材料失效 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]