考虑损伤判据温度相关性的相场法模拟氧化铝热冲击裂纹扩展

Thermal Shock Crack Propagation of Alumina Simulated With the Phase-Field Method Under Temperature-Dependent Damage Criteria

氧化铝陶瓷材料的力学性能受温度影响显著,因此使用相场法模拟热冲击裂纹的扩展时有必要考虑损伤判据的温度相关性.在现有热力学相场模型的基础上通过引入温度相关性损伤判据,修正了相场模型的控制方程.利用该模型对氧化铝陶瓷热冲击实验进行有限元模拟,并将模拟结果与氧化铝热冲击实验结果和不考虑温度相关性损伤判据的有限元模拟结果进行对比.结果表明,通过引入温度相关性损伤判据,可实现对热冲击裂纹的萌生和扩展过程更合理的模拟.

The mechanical properties of alumina ceramic materials are significantly affected by temperature,so it is necessary to consider the temperature dependence of the damage criteria during the simulation of thermal shock crack propagation with the phase-field method.Based on the existing thermodynamic phase-field model,the governing equations for the phase-field model were modified through introduction of the temperature-dependent damage criterion.Then the revised phase-field model was used to simulate the thermal shock experiment of alumina ceramics,and the simulation results were compared with the experimental results and the finite element simulation results without temperature-dependent damage criteria.The results show that,introduction of the temperature-dependent damage criterion helps more reasonably simulate the initiation and propagation process of thermal shock crack.