Structure-Mechanical Property-Formability Relationships for 444-Type W-Containing Ferritic Stainless Steels

We describe here structure-mechanical property-formability relationships for 444-type ferritic stainless steels with different contents of W. The microstructure, texture and grain boundary character that evolved during hot rolling, cold rolling and annealing process were characterized in detail to predict the effect of W. The microstructure of annealed plates became more uniform and finer with the increase in W content, which led to an increase in both strength and elongation. Alloying with W significantly influenced texture development and texture intensity. The addition of W accelerated the transformation of rolling texture to stable components benefitting the formation of recrystallized gamma -fiber texture, and also effectively restrained the deviation from the exact gamma -fiber after cold rolling and annealing. Ferritic steel with 1.12 wt.% W exhibited excellent formability because of the presence of intense gamma -fiber texture and fine recrystallized grains.