Texture evolution in polycrystalline FeMnAlNi shape-memory alloy sheets

For polycrystalline Fe-based shape-memory alloys, the crystallographic texture is critical for relieving grain boundary constraints and optimizing mechanical properties, such as superelasticity and ductility. In this study, the texture evolution in a polycrystalline FeMnAlNi alloy subjected to cold rolling, primary recrystallization, and secondary recrystallization was systematically investigated using electron backscatter diffraction. Starting from a body-centered cubic (BCC) + face-centered cubic (FCC) two-phase microstructure, the 94.1 % cold-rolled sample exhibited a predominantly FCC phase with a strong Brass texture component accompanied by a minor volume fraction of the BCC phase. After primary recrystallization annealing, the orientations of the grown BCC grains were governed by the Kurdjumov–Sachs orientation relationship with the adjacent FCC grains. These BCC grains predominantly exhibited {433}<337> and {100}<011> orientations. When the temperature exceeded ∼1120 °C, abnormal grain growth of a small fraction of {211}<011>-oriented BCC grains occurred concurrently with the dissolution of the FCC phase. Furthermore, the colonial structure and Σ9 boundary likely contributed to the exceptional grain boundary migration rate, ultimately yielding a pronounced {211}<011> texture in the BCC single-phase microstructure.