不同初始组织的3D晶粒长大仿真及其准稳态分布研究

Simulation of 3D Grain Growth from Different Initial States and their Quasi-Stationary State Distributions

摘要:

设计了晶粒尺寸分别呈β=2.96 与β=3.47的Weibull分布的2种3D初始晶粒组织，采用Potts模型Monte Carlo改进算法进行了界面曲率驱动的3D晶粒长大过程的仿真研究。晶粒仿真长大过程遵循抛物线长大规律，且晶粒生长指数非常接近于理论值0.5。仿真结果表明：源于2种初始组织所得准稳态晶粒尺寸均趋于β=2.80±0.03的同种Weibull分布，准稳态晶粒面数则均呈对数正态分布。进一步分析发现，刘国权及其合作者近年来基于不同长大速率理论模型导出的两类3D准稳态晶粒尺寸分布函数与本文仿真实验所得数据相互吻合。

Abstract:

The 3D capillarity-driven grain growth process was simulated using a modified Potts Monte Carlo technique, starting from two initial microstructures with the grain size distributions well described by Weibull functions of b=2.96 and b=3.47, respectively. The process obeys the grain growth parabolic law very well, with the time exponent n very close to 0.5. The results show that the quasi-stationary grain size distributions finally turn to the same Weibull distribution with b=2.80±0.03 for two different initial microstructures and the grain face number distributions turn to a lognormal distribution. The two analytical 3D grain size distribution functions coincide with the two kinds of functions derived by Liu Guoquan and his coworkers recently based on the different grain growth rate equations.