Synthesizing Annealing Twins in Three-Dimensional Voxel-Based Microstructures

Abstract

The five-parameter grain boundary character distribution (GBCD) of a material contains both the grain boundary plane orientation and the lattice misorientation information. This work focuses on generating three-dimensional microstructures that match the full five-parameter GBCD obtained from experimentally observed microstructures. In face-centered cubic metals, the density of high symmetry boundaries is often maximized in order to improve grain boundary dependent properties, such as the resistance to intergranular corrosion and fatigue cracking. Twinning events have been found to be very effective in introducing these high symmetry boundaries that are denoted by low sigma values for Coincident Site Lattice relationships. Therefore, in this investigation, microstructures that contain annealing twins are of particular interest. The statistics that are used to quantify the differences between the synthetic and experimentally observed structures are texture or orientation distribution (OD), GBCD, number and area fractions of S3 and coherent S3 boundaries, S3 cluster distribution, and twin density.