Influence of microstructural and compositional variables on hot working of steel

Abstract

Initially, a brief review is presented of the techniques used for the measurement of the strength and ductility of steels under hot-working conditions. Laboratory hot-workability tests are widely used in practice to study steel processing problems, and a number of situations are described where the cause has been related to variations in microstructure and composition. The presence of non-equilibrium microstructural phases such as delta ferrite in stainless steels and carbide segregates in bearing steels can result in a marked deterioration in hot workability. The form and distribution of inclusions in free-cutting steels influence rolling behaviour, and under certain conditions splitting of the ends of the stock can occur. In the case of carbon and low-alloy steels, there may be a marked influence from the residual content of the steel in conjunction with the heating conditions used to prepare the steel for hot working.