{001}⟨101⟩ texture evolution by preferential dynamic grain growth in Ti–37 mol%Nb alloy under plane strain compression at high temperatures

Abstract

{001}< 101 > texture evolution in Ti-37 mol%Nb (Nb-46.5 mass%Ti) alloy was determined under plane strain compression at the temperatures of 800 degrees C, 950 degrees C, and 1100 degrees C, in which preferential dynamic grain growth (PDGG) took place. At lower temperature and higher strain rate such as 800 degrees C-10(-2)/s, almost no grain growth occurred in the transverse direction (TD), and the alpha-fiber + near {111}< 110 > in the gamma-fiber texture was developed, which was a stable orientation as deformation texture. At higher temperature and lower strain rate such as 1100 degrees C-10(-3)/s, the grain growth along the TD remarkably appeared by grain boundary bulging, and an extremely high pole density of the texture near the alpha-fiber, especially the rotated cube {001}< 101 >, evolved. A planar dislocation structure with pile-ups appeared and individual dislocations were uniformly distributed in the grains. The rotated cube texture fulfills the conditions of the deformation stability and the low Taylor factor in accordance with the PDGG mechanism. The essential aspect of the mechanism is the preferential growth of grains with a stable orientation for deformation and a low Taylor factor in the given deformation mode.