Effect of Hot Band Annealing Processes on Microstructure, Texture and r-Value of Ferritic Stainless Steel

Abstract

The effect of hot band annealing processes, namely simulating batch annealing and continuous annealing, on microstructure, texture, grain boundary character and r-value of ferritic stainless steel was investigated. The hot band displayed a highly elongated ribbon-like structure and a pronounced deformation texture. The fully recrystallized grains were observed after continuous annealing while the “typical” hot rolled structure was remained after batch annealing. Also, the α-fibre texture formed during hot rolling almost disappeared after continuous annealing and a weak γ-fibre texture was obtained. By contract, the α-fibre texture remained very stable after batch annealing. After cold rolling and recrystallization annealing, the favorable γ-fibre texture was achieved in the continuous annealed steel. Instead of forming the γ-fibre texture, the recrystallization texture was notably shifted toward {223}<582> in the batch annealed steel. Finally, the improvement in drawability with high r-value and low Δ r-value were also displayed in sheet through the initial continuous annealing process.