Computer simulation of texture evolution during grain growth: effect of boundary properties and initial microstructure Original Research Article

We investigate orientation selection during grain growth by computer simulation in two-dimension using the phase-field method. The model characterizes misorientation in three-dimension with all three degrees of freedom. The systems considered consist of a single cube component embedded in a matrix of randomly oriented grains in the initial microstructure. The average grain size and size distribution are similar for both textured and randomly oriented grains. Starting from various fractions and spatial distributions of the cube component, we show that the effect of boundary energy anisotropy on texture development differs drastically from that of mobility anisotropy. In all cases the fraction of the cube component increases if boundary energy is anisotropic, and decreases if boundary mobility is anisotropic while energy is isotropic. Similar to previous studies, when boundary energy is anisotropic the misorientation distribution is no longer time-invariant and grain growth kinetics deviates from the behavior of isotropic grain growth. However, mobility anisotropy could also alter misorientation distribution and hence affect grain growth kinetics, which is different from the results obtained previously for systems of either random or single-component texture. The initial spatial distribution of the texture component plays an important role in determining the time-evolution of the misorientation distribution and hence affects the overall kinetics of texture evolution and grain growth. The simulation results are analyzed using Turbullʹs theory on grain growth. It is found that even though many individual factors affect texture evolution during grain growth, the key factor that really controls the process is the local grain boundary energy density.