| 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. Microstructures that contain annealing twins are of particular interest in this investigation. 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 Sigma3 and coherent Sigma3 boundaries, Sigma3 cluster distribution, and twin density.;Due to the unique features of the annealing twins, a twin insertion algorithm is used to generate annealing twins in the synthetic microstructures. To demonstrate the capability of the twin insertion algorithm, the twin grains were removed from an experimental structure, Inconel 100, and were then regenerated with the twin insertion algorithm. The largest Sigma3 cluster measured in the experimental Inconel 100 structure consists of 98 grains, which can only be observed by analyzing the fully-reconstructed 3D structure.;The main simulation code used in this study is the grain orientation assignment algorithm. This algorithm consists of taking a digital three dimensional microstructure and assigning orientations to the grains through a simulated annealing based optimization method, such that the generated orientation distribution and misorientation distribution or five-parameter GBCD will match the user-defined values. The generation methods used in creating the digital voxel-based microstructures and the methods used to reconstruct experimentally measured structures with the dual-beam microscope are discussed. From performing the grain assignment algorithm with different textures and misorientation distribution (MD) as the target distributions, it was found that when the OD and MD are incompatible, a compromise must be made in order for the two distributions to fit together in the structure. The studies of matching several textures, MD, and GBCD to various microstructures indicated that the neighbors per grain and grain boundary areas have significant effects on the possible OD, MD, and GBCD that can exist in the structure. |
