Strain hardening features of ferrite-martensite steels

A model is suggested for strain hardening of ferrite-martensite steels taking account of the stereology of structural components and redistribution of strains between them during loading. Analytical expressions are obtained making it possible to calculate the yield stress for a two-phase steel at any instant of deformation and the value of true equilibrium strain depending on such structural factors as the volumetric proportion of martensite, its carbon content, and the size and distribution of ferrite grains and martensitic areas. Experimental and calculated data are compared.Translated from Problemy Prochnosti, No. 6, pp. 43–48, June, 1990.