Article révisé par les pairs
Résumé : By analogy with the role of perfect dislocations in facilitating Kurdjumov-Sachs type transformations, it is proposed that partial dislocations may be responsible for Nishiyama-Wassermann transformations. Such an interpretation can account for the presence of both "positive slip" and "negative slip" variants within individual grains, a hitherto unexplained phenomenon. (C) 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.