Austenite retention in low Al/Si multiphase steels

The possibility of obtaining multiphase steels with considerable fractions of retained austenite, which is of key interest for the occurrence of the transformation-induced plasticity (TRIP) effect, is investigated in steels with low amounts of Si and Al. Special emphasis is given to the microstructural observation of this phase, since its volume fraction, distribution and stability, in relation to the carbon content, will determine the efficiency of the TRIP effect and thus of the resulting mechanical properties. Mechanical testing was carried out in order to measure the efficiency of the retained austenite transforming to martensite. (c) 2006 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.