A. Itami et al., PLASTIC STABILITY OF RETAINED AUSTENITE IN THE COLD-ROLLED 0.14-PERCENT-C-1.9-PERCENT-SI-1.7-PERCENT-MN SHEET STEEL, ISIJ international, 35(9), 1995, pp. 1121-1127
Mechanical properties of a 0.14%C-1.9%Si-1.7%Mn TRIP steel have been s
tudied especially from the aspect of the plastic stability of retained
austenite which was varied by changing bainite transformation time at
400 degrees C. The plastic stability of retained austenite and the st
rength-ductility balance at room temperature are improved with the inc
rease in C content in retained austenite after optimizing the bainite
transformation time in the continuous annealing process. Martensitic t
ransformation can occur from the plastically unstable retained austeni
te with low C content. The kinetics model for deformation-induced mart
ensitic transformation explains the experimentally obtained change in
volume fraction of retained austenite with plastic strain in terms of
the C content in retained austenite.