Austenite stability of ultrafine-grained transformation-induced plasticity steel with Mn partitioning

The factors leading to the room temperature stabilization of austenite were investigated for an ultrafine-grained 6 mass% Mn transformation-induced plasticity steel. The size effect of ultrafine austenite grain and the partitioning of Mn to austenite during intercritical annealing were the two main contributions to the austenite stability. Mechanical stabilization of the austenite was not a factor contributing to the austenite stability due to the very low dislocation density of the austenite grains. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.