Monte Carlo simulation of microstructure evolution based on grain boundary character distribution

A Monte Carlo simulation of microstructure evolution was conducted with emphasis on grain growth anomaly and texture formation arising from grain boundary characteristics. Microstructures consisting of strategically varied grain size, grain boundary mobility and texture components were generated. It was found that the initial grain size was of the most significant parameter that determines the topographical properties of the final microstructure. Contrary to some observations and expectations, high-energy grain boundaries of high mobility did not necessarily vanish first but sometimes persisted and even increased in areal fraction depending on the local distribution of characteristics. In a microstructure with two texture components, an abnormal gain growth occurred when a large grain with high mobility selectively grew consuming surrounding small grains. From the analysis of the variation of grain boundary fraction and associated energy reduction, it was concluded that minimization of the total energy of the system, instead of the local instability, governed the evolution characteristics of the microstructure.