【摘要】 为了探索PCrNi3MoV钢加热或高温下晶粒长大规律，采用水平集法进行数值模拟，研究其在不同加热条件下的晶粒长大组织演变行为，同时使用Gleeble-1500D热模拟试验机对PCrNi3MoV钢进行1 000～1 100℃下保温10～2 000 s的一系列等温条件下奥氏体晶粒长大试验。采用Burke-Turnbull晶粒长大模型，利用反算法求得材料参数中间变量M_bγ_b终值在1 000℃、1 050℃和1 100℃时分别为7.51×10^-6 mm²s^-1、2.03×10^-5 mm²s^-1和4.26×10^-5 mm²s^-1,时间指数n终值分别为0.532 4、0.802 6和0.771 1,这表明1 000℃下晶粒长大趋势显著低于1 050℃和1 100℃的长大趋势。为了解决n值不一致的问题，改进了Burke-Turnbull晶粒长大模型，改进模型的决定系数R²为0.993 2。采用改进的模型进行水平集法晶粒长大数值模拟，最后分析了水平集法模拟的奥氏体晶粒组织长大规律。结果表明：在2 000 s的范围内，1 000℃近似长大70%仍然属于细晶、1 050℃近似长大500%（1 000℃的7倍）、1 100℃近似长大600%（1 000℃的9倍）,后两者属于粗晶，水平集法模拟的晶粒长大结果与试验结果均相吻合。更多还原

【Abstract】 In order to explore the grain growth rule of PCrNi3Mov steel during heating or at high temperature,the level set method was used for numerical simulation to study the grain growth micro structure evolution behavior under different heating conditions.At the same time,physical tests of isothermal grain growth of PCrNi3Mov steel at 1 000～1 100 ℃ for 10～2 000 s were carried out by Gleeble-1500D thermal simulator for verification.The Burke-Turnbull grain growth model was used in the level set method,and the model precision parameter values（final value） with the reverse methods were obtained.The material parameter intermediate M_bγ_b final value at 1 000℃,1 050℃ and 1 100℃ were 7.51×10^-6 mm² s^-1,2.03×10^-5 mm²s^-1 and 4.26×10^-5 mm² s^-1 respectively.The final values of n were 0.532 4,0.802 6 and 0.771 1,respectively,indicating that the grain growth trend at 1 000 ℃ was significantly lower than that at 1 050 ℃ and 1 100 ℃.In order to solve the problem of inconsistent n values,an improved Burke-Turnbull grain growth model with a determination coefficient R² of 0.993 2 was proposed.The numerical simulation of grain growth by level set method by using this improved model was carried out,and the austenitic grain growth was analyzed.The results show that the grain growth still belongs to fine grain at 1 000 ℃,the grain growth 500 %（7 times of 1 000 ℃）becomes coarse grain at 1 050 ℃,growth 600%（9 times of 1 000 ℃） becomes coarse grain too at 1 100 ℃during the 2 000 s.The simulated grain growth results are consistent with the experimental results.更多还原