Kinetics of Bainite Transformation in Multiphase High Carbon Low-Silicon Steel with and without Pre-Existing Martensite

In the present study, isothermal decomposition of austenite to bainite in 1.0 wt% carbon, 0.21% silicon steel during partitioning step a quenching and (Q&P) heat treatment has been investigated dilatometer temperature range 200 350 °C compared conventional austempering treatment. The transformation was shortened by about 75% presence pre-existing martensite (QP). kinetics is described well-known Avrami equation. calculated parameter ‘n’ equation shows that forms absence (TT) at constant nucleate rate, while martensite, nucleation interface controlled. overall activation energy, equation, ranges from 64 110 kJ/mol. outcomes this investigation provide guidelines for development multiphase microstructures, including high-carbon low-silicon steel, within an industrially acceptable time scale mechanical performance.