On the α → γ transformation during dynamic thermal cycles

Rapid cycles of heat treatment were given to various Fe-C alloys with different initial morphology and carbon cotent between 0.03 and 0.98%C. The specimens were heated up to temperatures between 600 and 1000 C by passing a high-amperage (103-104 A) alternating current through them. The microstructural investigation was performed by light and electron microscopy as well as electron microprobe measurements. The results of the study are discussed in terms of the mechanisms of phase transformations, taking account of various parameters like carbon content, primary microstructure, temperature and heating rate. (orig.)