THE INFLUENCE OF THE ALLOYING ELEMENTS UPON THE TRANSFORMATION KINETICS AND MORPHOLOGIES OF FERRITE PLATES IN ALLOY-STEELS

A series of Fe-C-X and Fe-C-X1-X2 alloys in which X, X1, and X2 either raise or depress the activity of C in gamma were investigated by auto dilatometer, optical microscopy, and transmission electron microscopy (TEM) to reveal the relations among the chemical composition, transfor mation kinetics, and morphology of ferrite plates. The incubation time of austenite decomposition at the nose temperature in the time-temper ature-transformation (TTT) diagrams, the concentration of C in gamma i n contact with the alpha/gamma boundary, and the growth rate of ferrit e were evaluated to estimate the magnitude of the solute drag-like eff ect (SDLE) for the different alloying elements used. All the results a re consistent qualitatively with the SDLE hypothesis.