Evolution of strain induced precipitation in Nb and V-microalloyed steels and influence on mechanical properties

摘要

By means of hot torsion tests and applying the "Back Extrapolation" method, the static recrystallization kinetics in V and Nb-microalloyed steels has been determined and the recrystallization-precipitation-time-temperature (RPTT) diagrams have also been plotted. The RPTT diagrams graphically show the Recristalization-Precipitation interaction and simultaneously the determination of the static recrystallization critical temperature (SRCT). The mentioned temperature represents the limit between the two phases, before and after of the precipitation. The activation energy for static recrytallization of the austenite before and after precipitation has also been determined. The present study is completed with the determination of the precipitate size distribution diagrams by means of TEM analysis.