Assignment of individual orientation by gaussian distribution and Monte-Carlo grain growth simulation by grain boundary character distribution (GBCD) in Fe-3%Si alloy

초록

In an effort to investigate the effect of GBCD on the evolution of microstructure, a Monte-Carlo computer simulation method was developed in which the texture of real material was closely reconstructed in the simulated microstructure. The method consists of extracting the volume fraction and the Gaussian half-width from the experimental ODF of a Fe-3%Si alloy and planting them into the simulated microstructure. Using the reconstructed microstructure, recrystallization texture formation characteristic of this alloy was studied with a particular focus on the anisotropic mobility of grain boundaries. By deliberately assigning a 1000 times high anisotropic mobility to the grain boundaries with a misorientation angle in the range of 20 to 45 degrees, abnormal grain growth phenomenon was analyzed. It was found that selective growth of grains occurred when they are subject to the pertinent conditions such as the high mobility themselves concomitant with a presence of neighboring low-mobility grains. Grains with the Goss orientation conformed, rather than exceptional, to this general pattern of selective coarsening. Therefore, the present result strongly suggests that the theory of Hayakawa et al. - based on the selective growth of Goss grains with the particular boundary misorientation angles - needs to be modified so as to incorporate more general cases.