基于物质跃迁能垒改进正常晶粒长大的Monte Carlo模拟

Modified Monte Carlo simulation of normal grain growth considering energy barrier for mass transition

在采用改进的Monte Carlo方法模拟正常晶粒的长大过程时,考虑到实际晶粒长大过程中物质状态跃迁需克服一定能垒,把跃迁能垒引入到状态跃迁概率计算中,使模拟过程所含物理意义更为明确。模拟结果表明:在各种模拟条件下得到的模拟晶粒长大指数为0.472～0.493,接近理论的晶粒长大指数(0.5)。改变模拟温度和能垒等模拟条件后,得到的晶粒形貌演变过程、晶界分布拓扑特征以及晶粒长大速率等模拟结果也均与晶粒长大动力学相关理论和实际晶粒长大规律相吻合。

Considering that an energy barrier should be conquered to realize the mass transition during the real grain growth process,the Monte Carlo method was modified by introducing the energy barrier for mass status transition into the evaluation of mass fransition probability to simulate the normal grain growth.The aim of modification was to improve the physical significance of simulation.The simulation results show that the simulated grain growth exponent is 0.472-0.493,which is close to the theoretical value of 0.5.With the variation of simulation temperature and energy barrier,the simulation results about the grain morphology development,the topological characteristic of grain boundary and the variation of grain growth rate are all in accordance with the theories and real rules of normal grain growth kinetics.