Texture and Anisotropy Mechanism of Oxide Dispersion‐Strengthened FeCrAl Cladding Tube Produced by Pilger Cold Rolling and Annealing

This work studies the yield strength, fracture modes, and anisotropic evolution of oxide dispersion‐strengthened (ODS) FeCrAl cladding tubes when deformed along different directions. The results show that the {112} <111> slip system is activated as the primary slip system during the ODS FeCrAl cladding tube deformation. The development of textures in different directions is entirely different for cladding tube, i.e., in a 45° direction the initial {001} texture passes through the {112} <131> orientation transformation to the {111}<112> γ‐fiber texture; in transverse direction (TD) the initial {001} texture passes through the {001}<130> orientation to transform into the {001}<110> α‐fiber texture. In rolling direction (RD), medium strength γ‐fiber textures and α‐fiber textures are produced simultaneously. The banding of the {111}<110> and {112}<110> textures in the RD results in an uneven distribution of shear strain, which leads to premature brittle fracture of the specimen. In the 45° direction and TD, strain softening occurs in the shear band, resulting in ductile fracture of the cladding tube. The remarkable linear relationship between the yield strength and the Taylor factor indicates that the observed yield anisotropy depends mainly on the initial {001}<100> recrystallized cubic texture rather than the high aspect ratio flat shape grains along the RD.