Texture Formation in a Polycrystalline Fe–Ni–Co–Al–Ti–B Shape Memory Alloy

Abstract

In polycrystalline Fe-Ni-Co-Al-based shape memory alloys, control of the recrystallization texture is significantly important to improve the ductility by suppressing the brittle precipitates of the β-B2 phase at grain boundaries during aging treatment. In this paper, the texture evolution in the recrystallization process was systematically investigated by means of the electron backscatter diffraction (EBSD) method in an Fe–Ni–Co–Al–Ti–B polycrystalline alloy. The development of a {110}<112> texture was confirmed in the 98.5% cold-rolled sheet specimen. After primary recrystallization annealing, the γ matrix containing the β phase showed the continuous recrystallization remaining in the same orientation with a deformation texture after annealing at 1000°C. Grain growth of the γ phase was interrupted by the β phase. Then, abnormal grain growth of {210}<001> grains began occurring in concurrence with the dissolution of the β phase and the main recrystallization texture changed from {110}<112> to {210}<001> at temperatures higher than 1100°C.