Martensite-to-austenite reversion and recrystallization in cryogenically-rolled type 321 metastable austenitic steel

The annealing behavior of cryogenically-rolled type 321 metastable austenitic steel was established. Cryogenic deformation gave rise to martensitic transformation which developed preferentially within deformation bands. Subsequent annealing in the range of 600 C to 700 C resulted in reversion of the strain-induced martensite to austenite. At 800 C, the reversion was followed by static recrystallization. At relatively-low temperatures, the reversion was characterized by a very strong variant selection, which led to the restoration of the crystallographic orientation of the coarse parent austenite grains. An increase in the annealing temperature relaxed the variant-selection tendency and provided subsequent recrystallization thus leading to significant grain refinement. Nevertheless, a significant portion of the original coarse grains was found to be untransformed and therefore the fine-grain structure was fairly heterogeneous

Iron alloys with new functional properties obtained during reverse martensitic transformation

It was shown that different types of the austenite (homogeneous and inhomogeneous polyhedral, or submicrocrystalline and nanocrystalline plate austenite) can be formed, providing new functional properties of various steels and alloys. The austenite formed during a partial $\alpha\to\gamma$ transformation increases considerably the strength of the martensite, enhances the coercive force and improves the square shape of the hysteresis loop of maraging steels. The thermal expansion coefficient of the austenitic alloy type 32Ni can be adjusted over broad limits thanks to different $\alpha\to\gamma$ transformation conditions. A stainless steel with a structure of alternating laths of the martensite and the austenite has a high resistance to radiation void formation

Effect of microtwinning on low-temperature properties of austenitic Fe-Ni steels

14.00; Translated from Russian (Struktura i Fiziko-Mekhanicheskie Svoistva Nemagnitnykh Stalei Nauka Moscow 1986 p. 130-134)SIGLEAvailable from British Library Document Supply Centre- DSC:9023.19(VR--3363)T / BLDSC - British Library Document Supply CentreGBUnited Kingdo