FORMATION OF epsilon PHASE IN Fe-Mn ALLOYS UNDER HIGH PRESSURE AND ITS STABILITY UNDER TENSILE STRESS.

Abstract

The A//s and M//s temperatures in the martensitic transformation of Fe-Mn alloys (containing 4. 80 to 28. 24% Mn) under hydrostatic pressurs up to 35. 5 kbar were measured by DTA. The gamma yields epsilon and epsilon yields alpha transformations as influenced by pressure, temperature, and tensile stress are discussed in terms of thermodynamics. Increase in tensile strength was obtained only for the specimens in which the epsilon phase had been formed by pressurizing. An explanation is given.