一种优化动态回复阶段位错密度增量的方法

A method for optimizing the dislocation density increment at dynamic recovery simulation

为了进一步改善瞬态形核率动态再结晶CA模型的动态回复阶段模拟精度,提出了采用应力差闭环控制-黄金搜索法取代唯象的位错密度增量模型来搜索、优化动态回复位错密度增量的方法,通过HPS485wf钢动态再结晶过程仿真和热模拟实验检验了该方法的合理性和应用效果。结果表明,这一方法合理、可行,能优化位错密度增量以提高动态回复阶段和动态再结晶全程的模拟精度和稳定性,较比传统的恒形核率动态再结晶CA模型的动态回复阶段和动态再结晶全程的模拟精度分别提高了98.91%和91.71%,较比瞬态形核率动态再结晶CA模型的动态回复阶段和动态再结晶全程的模拟精度分别提高了95.16%和49.47%。

A method to further improve the simulation accuracy of the dynamic recrystallization cellular automata model contained transient nucleation rate （shortly called DRX-TN-CA model） was proposed. Its main character is that the phenomenologieaL model of dislocation density increment is replaced by the closed-loop control of stresses difference and golden search, so that the dislocation density increment at dynamic recovery stage can be optimized. Its rationality and effectiveness were examined by use of the dynamic recrystallization simulation and thermal simulation experiments for HPS485wf steel. The results show that this approach is reasonable and practicable, and can optimize dislocation density increment to improve the accuracies at dynamic recovery and dynamic recrystallization simulation, which are increased up to 98.91% and 91.71% compared with traditional CA model, and are raised up to 95. 16% and 49.47% compared with DRX-TN-CA model, respectively.