基于Laasraoui-Jonas位错密度理论的TA10钛合金微观组织演变模拟

Simulation of microstructure evolution of TA10 titanium alloy based on the Laasraoui-Jonas dislocation density theory

为模拟TA10钛合金的微观组织演变,采用Gleeble-1500D热/力模拟试验机,在变形温度为800~1050℃,应变速率为0.01~5 s^（-1）的条件下,对TA10钛合金做了热模拟压缩实验。通过处理实验数据,得到不同变形条件下的动态回复软化率系数r,分析了变形温度和应变速率对r值的影响;建立了TA10钛合金的Laasraoui-Jonas（L-J）位错密度模型,结合元胞自动机法（Cellular Automata,CA）对TA10钛合金的微观组织演变进行模拟,并将模拟结果与实验结果进行对比。结果表明：TA10钛合金动态回复软化率系数r的值随应变速率的增加而减小,随温度的升高而增大;模拟结果与实验结果基本吻合,所构建的L-J位错密度模型能够准确预测TA10钛合金在热压缩过程中的微观组织演变。

To simulate microstructure evolution of TA10 titanium alloy,hot compression tests of TA10 titanium alloy were conducted by the Gleeble-1500 D thermal simulation test machine under the deformation temperature of 800-1050 ℃ and strain rate of 0. 01-5 s^（-1）.The recovery parameter r under different deformation conditions was calculated based on the experiment data,and the effects of temperature and strain rate on the recovery parameter r were analyzed. The Laasraoui-Jonas（ L-J） dislocation density model of TA10 titanium alloy was established,the microstructure evolution of TA10 titanium alloy was simulated by using the cellular automaton（ CA） method,and the simulation results were compared with the experimental one. The results show that the recovery parameter r of TA10 titanium alloy decreases with the increase of strain rate and increases with the increase of temperature. The simulation results agree well with the experimental results,which prove the accuracy of the established L-J dislocation density model for predicting the microstructure evolution of TA10 titanium alloy during hot compression.