Nucleation of Recrystallization in Cu-8%at. Al Alloy Studied by Orientation Mapping in TEM
The nucleation of new grains during annealing in high purity single crystals of Cu-8%wt. Al alloy with initial (112) orientation has been characterized by detailed transmission electron microscopy (TEM) orientation measurements. The samples were channel-die deformed and then recrystallized to form a substructure composed of a mixture of deformation twins, shear bands (SBs) and the recrystallized grains. Substantial progress in understanding the mechanism of texture transformations at the early stages of recrystallization was possible thanks to orientation mapping using TEM. Microtexture analysis of partly recrystallized samples indicates a simple 25-40o (<111> or <112>) relation, most frequently observed during the early stages of recrystallization between single nuclei and one of the two as-deformed groups of components (twins or matrix). As recrystallization proceeds, recrystallization twinning develops strongly and facilitates rapid growth of the recrystallized phase. The first and higher generations of twins systematically tend to obscure the initial crystallographic relation between the deformed state and the recrystallization nuclei.
S.-J.L. Kang, M.Y. Huh, N.M. Hwang, H. Homma, K. Ushioda and Y. Ikuhara
H. Paul et al., "Nucleation of Recrystallization in Cu-8%at. Al Alloy Studied by Orientation Mapping in TEM", Materials Science Forum, Vols. 558-559, pp. 283-288, 2007