DILATOMETRIC AND CALORIMETRIC STUDY OF THE GRAPHITIZATION OF HIGH CHROMIUM CAST-IRON

This study is devoted to the graphite formation in high chromium cast iron (8% Cr) and especially to the determination of the conditions for secondary graphite formation using suitable thermal treatments. The s olidification of the studied iron was examined by differential thermal analysis (DTA). The effect of high temperature treatments were examin ed using both differential calorimetry and dilatometry. Primary graphi te occurs at a temperature of 950 degrees C. Secondary graphite grows on primary graphite during high temperature austenite destabilisation. The shape and the quantity of secondary graphite depend on the treatm ent temperature.