Modification of Rule of Mixtures for Estimation of the Mechanical Properties of Dual-Phase Steels

The mechanical properties of dual-phase (DP) steels were correlated with the amount of martensite and its carbon content. The application of rule of mixtures for predicting the mechanical properties was critically discussed. Subsequently, a modified rule of mixtures was developed to estimate the mechanical properties of DP steels, which accounts for the variation of carbon content in martensite as a function of its volume fraction. The proposed model was able to predict the observed trends and values of hardness, yield stress, and tensile strength in a DP steel with ~0.1 wt.% C. Then, its applicability was also verified for a DP steel with ~0.2 wt.% C to cover the usual range of carbon content in DP steels. As a result, this simple and effective approach is anticipated to find application in estimating the properties of DP steels.