|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Phase Transformations in Multi-component Systems: An MPMD Symposium Honoring Gary R. Purdy
||Carbon Enrichment in Austenite during Ferrite and Bainite Transformations in Fe-Mn-C Based Alloys
||Goro Miyamoto, Tadashi Furuhara
|On-Site Speaker (Planned)
In order to discuss transformation mechanism, carbon content in austenite (Xcγ) during isothermal transformations was measured directly using FE-EPMA. It was found in Fe-(1.5 and 2)Mn-C alloys that Xcγ after the cessation of fast growth of proeutectoid ferrite at relatively high temperature agrees well with the transition composition of NPLE/PLE model. In contrast, Xcγ in the stasis of bainitic transformation deviates to lower carbon content and is rather close to T0’ composition. This behavior can be understood by undercoolings from NPLE/PLE transition composition or T0 composition both in diffusional and diffusionless mechanisms, respectively. Recently we have found that small amount of Mo influences Xcγ significantly, in contradiction to diffusionless theory. On the other hand, Xcγ in Fe-3Mn-C alloy can be explained more reasonably by diffusionless mechanism than diffusional mechanism. Those results indicate the both diffusional and diffusionless mechanisms need to be revised.
||Planned: A print-only volume