An approach to predict the depth of the decarburized ferrite layer of spring steel based on measured temperature history of material during cooling

Abstract

An approach is proposed to predict in sequence the phase transformation behavior, scale thickness, and depth of the decarburized ferrite layer of spring steel during cooling process once the measured temperature history of the spring steel were provided. This proposed approach successively couples a set of mathematical models describing the temperature evolution, phase transformation, oxidation, and decarburization. The dilatometry experiment was performed to verify the proposed method. Results reveal that the measured depth of the decarburized ferrite layer agreed well with the predicted depth. The predicted pearlite volume fraction nearly coincided with the measured value as well. © 2014 ISIJ.