|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Advanced High Strength Steels V
||Carbon Content in Carbide-free Bainite during Isothermal Transformations
||Irina Pushkareva, Babak Shalchi-Amirkhiz, Sébastien Y.P. Allain, Guillaume Geandier, Frédéric Danoix, Fateh Fazeli, Matthew Sztanko, Colin Scott
|On-Site Speaker (Planned)
||Sébastien Y.P. Allain
Even if carbide-free bainitic steels are now used in many applications for automotive construction (crankshafts, stamped parts), the nature of the bainitic transformation remains a bone of contention among metallurgists. In this study, we have coupled three different experimental techniques to understand carbon partitioning between austenite, bainite and possibly carbides during their transformation in isothermal conditions. The carbon contents were determined by in situ High-Energy XRay Diffraction experiments on synchrotron beamlines using precise mass balances enabled by the techniques as well as using the phase tetragonality. Direct measurements by Electron Energy Loss Spectroscopy and 3D Atom Probe Tomography have also been conducted ex situ in bainite laths at room temperature. For the studied conditions and compositions (Fe0.2%C2.2%Mn1.5%Si+Mo/V), the values found in bainite laths are about 0.1%C meaning that a large fraction of carbon is not available for austenite stabilization.