Ridging Control in Transformable Ferritic Stainless Steels

Abstract

An alloy design concept leading to an improved ridging resistance in the transformable ferritic stainless steels is introduced. It is based on achieving a small gamma-phase fraction at the ingot soaking temperature. The gamma-phase fraction is then increased to a maximum value during the early stages of hot rolling. The nucleation of gamma-phase islands in the ferritic matrix increases the fraction of transformed ferrite. The multiplicity of crystallographic orientations resulting from the alpha ->gamma and gamma -> I +/- transformations leads to a pronounced weakening of the as-cast texture and an increased ridging resistance.