Influence of pearlite morphology and heating rate on the kinetics of continuously heated austenite formation in a eutectoid steel

A model that describes the pearlite-to-austenite transformation during continuous heating in a eutectoid steel has been developed. The influence of structural parameters (such as the interlamellar spacing and edge length of pearlite colonies) and heating rate on the austenite formation kinetics has been experimentally studied and considered in the modeling. It has been found that the coarser the initial pearlite microstructure and the higher the heating rate, the slower the kinetics of austenite formation. Moreover, both the start and finish temperatures of the transformation slightly increase as the heating rate does, but the finish temperatures are more sensitive to that parameter. A good agreement (with an accuracy higher than 90 pct in the square correlation factor) between experimental and predicted values has been found.