Static Recrystallization of Hot Deformed Austenite and Induced Precipitation Kinetics in Vanadium Microalloyed Steels

Abstract

Using torsional tests and applying the back extrapolation method the kinetics of the static recrystallization of hot deformed austenite has been studied in three microalloyed steels with different vanadium contents and this has been modelled at temperatures above and below the static recrystallization critical temperature (SRCT). The SRCT has been found to be a function of the strain, the austenite grain size and naturally the microalloy contents, in this case N and V. A study has also been made of the kinetics of the precipitation induced by the strain and the precipitation-time-temperature (PTT) diagrams have been determined for the three steels. The no-recrystallization temperature {Tnr) has also been determined and the conclusion was reached that the difference between the Tnr and SRCT is mainly due to the austenite grain size, which is smaller in the determination of the Tnr due to the successive recrystallizations which occur before precipitation takes place. © 1994, The Iron and Steel Institute of Japan. All rights reserved.