Modelling of transformation kinetics in HSLA 100 steel during continuous cooling

Generalised Johnson and Mehl and Avrami type kinetic reaction rate equation s were applied to analyse the transformation behavior of HSLA-100 steel dur ing continuous cooling. Analysis of the dilatometric data for various cooli ng rates yielded the time exponent constant n and the activation energy Q. Using these 2 contents, it was possible to determine the amount and the tra nsformation temperature of austenite to acicular ferrite and bainite and fr action transformed. Detailed analysis of cooling curves yielded a correlati on between the transformation mode and the constants in the Avarami equatio n. Using these 2 constants only, it was shown that the entire CCT diagram f or HSLA steels could be predicted. The results are in good agreement with t he experimental value.