Al2O3陶瓷的损伤型本构关系研究

利用INSTRON材料试验机和SHPB(分离式Hopkinson压杆)对Al2O3陶瓷材料进行了单轴压缩实验,测量了材料在不同应变率下的应力和真实应变。实验结果表明,Al2O3陶瓷是应变率敏感材料。通过对准静态和高应变率下的实验结果分析,认为损伤型ZWT非线性粘弹性本构关系能较好地描述Al2O3陶瓷在不同应变率条件下的力学行为,用遗传算法确定了本构关系中的参数。研究表明,所用损伤型ZWT本构方程和用遗传算法确定的参数在10-4-102s-1应变率范围内与实验结果吻合较好。

Study on the constitutive equation with damage of Al2O3 ceramics

The uniaxial compressive experiments of Al2O3 ceramics have been performed on the INSTRON material test machine and on the SHPB(split Hopkinson bar),and the curves of stress and true strain relation under different strain rate have also been gained.The experimental results show that the dynamic failure strength of the Al2O3 ceramics is dependent on the strain rate.By analyzing the experimental results from quasic-static and high strain rate the nonlinear viscoelasticity ZWT constitutive equation with damage has been introduced to express the mechanical characters of Al2O3 ceramics when strain rate is varied.The genetic algorithm has been utilized to define the parameters in the ZWT equation.The research shows that the calculation results of the ZWT constitutive equation and the parameters from genetic algorithms agree well with the experimental data when strain rate is between 10-4 and 102.