Texture Evolution In Nb-containing Ferritic Stainless Steels During Secondary Recrystallization

摘要

The texture evolution of three ferritic stainless steels (FSSs) with small additions of niobium after annealing at 1523 K for 2 h to promote secondary recrystallization (SR) was investigated. The 4-mm sheets containing 16wt.% Cr and distinct niobium contents (0.31, 0.37 and 0.56 wt.%) were obtained by hot rolling. Carbon and nitrogen contents for the two first steels are 0.02 wt.% C and 0.02 wt.% N. The third steel (0.56 wt.% Nb) contains 0.03 wt.% C and 0.03 wt.% N. The crystallographic textures were determined by conventional X-ray diffraction (XRD). The microstructure was characterized by scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The results show that hot band sheets display partial recrystallization. The Goss grains from primary recrystallization are found predominantly close to the surface. Pancake-like recovered grains displaying pronounced (001)<011> and α-fiber texture components are present at the center layer. Grains displaying abnormal growth are noticeable in the three samples after SR annealing. The texture of the hot bands was evaluated with respect to the composition and through-thickness effects. The results were compared to other FSSs and bcc materials such as low-carbon and silicon steels.