Misorientation angle distribution of deformation-induced boundaries provided by their EBSD-based separation from original grain boundaries: Case study of copper deformed by compression

Grain lattice fragmentation in heavily deformed metals is controlled by the formation of deformation-induced boundaries (DIBs) with misorientations evolving from low to high angles with increasing strain. A method is suggested allowing the separation of the contributions from DIBs and original grain boundaries to the overall misorientation angle distribution based on elects-on backscatter diffraction (EBSD) data. The peculiarities, accuracy and limitations of the method are considered by the example of copper under uniaxial compression at room temperature and 150 degrees C. It is shown that obtained distributions of DIB misorientation can be analyzed using their representation as a superposition of partial distributions. The partial distributions f(1) and f(2), which describe the low-angle interval, correlate with the distributions determined earlier by the transmission electron microscopy for two types of dislocation boundaries, while the third partial distribution h relates to the high angle DIBs, whose misorientations go beyond the range of the first two distributions. The rise of deformation temperature does not affect the character of misorientation distribution development.