The influence of niobium on the static recrystallization of hot deformed austenite and on strain induced precipitation kinetics

Of all the low-carbon microalloyed steels, Nb steels are the most widely used due to the fact that the strain induced precipitates are smaller than with vanadium or titanium steels. In this work the static recrystallization kinetics and induced precipitation of two niobium microalloyed steels are studied using torsional tests. The SRCT (static recrystallization critical temperature) is determined for each one of them as a function of the strain and the grain size, in the same way as has been employed with vanadium microalloyed steels. It has been shown that SRCT coincides approximately with the no-recrystallization temperature (Tnr), defined by Jonas et al, when the austenite grain size before the start of precipitation is the same