The relation between experiments and modeling of rapidly solidified 12Cr–Mo–V stainless steel

Solidification during melt spinning of a 12Cr–Mo–V stainless steel has been experimentally studied and numerically simulated. The resulting microstructures have been related to the unknown parameter h, i.e. the heat transfer coefficient between the substrate and the melt, by fitting the heat flow calculations and a phase selection model for a multicomponent system to the observed microstructures. Using the estimated value of the heat transfer coefficient, it was then possible to explain the observed structures in terms of growth velocities. High growth velocities (>0.2 m s−1) resulted in formation of metastable austenite as the primary phase near the chill side of the ribbon. Upon quenching to room temperature, this austenite transformed into martensite. At a distance of about 15 μm from the chill surface, the growth velocity of the solid/liquid interface decreased (<0.2 m s−1), allowing the stable ferrite phase to form as the primary phase. This approach provides a means to determine the solidification parameters and the microstructures formed in this rapid solidification process.