The influence of austenite prestrain above the M(sub d) temperature on the martensitic tranformation in Fe-Ni-Cr-C alloys

Abstract

Non-deformed specimens of a l6Cr-5Ni-O.3C alloy exhibited a lath morphology. Although the Mₛ decreased with increasing prestrain, the percent martensite transformed at -196°c increased, with respect to non-deformed samples for prestrains above the M(sub d) of less than 20%. A maximumin the stimulation effect was observed near 8% prestrain. This stimulation was associated with the nucleation of twinned plate martensite. The relative amount of lath martensite decreased with increasing prestrain above the M(sub d) so that a sample prestrained 20% showed predominantly plate martensite. A prestrain of 40% completely stabilized the transformation.