INFLUENCE OF AUSTENITE STRENGTH ON MARTENSITE START TEMPERATURE M(S)

It is known that austenite strength determines the morphology of the n ew phase during martensitic transformation. As the strength of austeni te influences the growth of a martensite crystal i.e. the movement of the austenite/martensite interface, a correlation between strength of the parent phase and M(s) has to exist. M(s) depends on thermodynamica l and mechanical properties of the alloys. To distinguish the individu al variables, austenite strength was changed by different hardening me chanisms: solid solution hardening, plastic deformation or both.