SUBGRAIN BOUNDARY IDENTIFICATION IN 3D EBSD DATA THROUGH FAST MULTISCALE CLUSTERING

摘要

Complete and accurate characterization of subgrain microstructural features permits study of the relationships among loading, microstructure and properties in plastically deformed metals. 3D electron backscatter diffraction data can produce reconstructed crystallographic volumes, however low angle subgrain boundaries cannot be determined simply with point-to-point misorientation thresholding because many are gradual transitions in orientation. We demonstrate a novel 3D implementation of the data segmentation technique Fast Multiscale Clustering, which uses a quaternion representation of orientation and a corresponding distance metric. Examples of the 3D segmentation of microbands and morphological analysis from the results are presented for die-compressed nickel single crystal and uniaxially loaded commercially pure aluminum.