Martensite and deformation twinning in austenitic steels

The structural changes that occur in highly-alloyed austenitic steels durin g plastic deformation have been studied as a function of temperature and pl astic strain. Stress-assisted and strain-induced martensites can occur, but also, deformation twinning can be identified by transmission electron micr oscopy. In the high-Mn austenite of Hadfield steel deformation is controlle d by slip and twinning over a wide temperature range. In high-Ni and more c omplex alloyed austenites (such as in TRIP steels) deformation involves mar tensite formation, both stress-assisted and strain-induced, but near room t emperature and above the influence of mechanical twinning? is also apparent . (C) 1999 Elsevier Science S.A. All rights reserved.