In Situ Observation of Retained Austenite Transformation in Low-Carbon Micro-Alloyed Q&P Steels

Retained austenite (RA) transformation and its role in the mechanical properties of three low-carbon micro-alloyed quenching partitioning (Q&P) steels was investigated utilizing situ tensile tests electron microscopy. Meanwhile, RA’s strain-induced martensite (SIMT) analyzed discussed terms strengthening mechanism. The results show that ductility Q&P relies on size morphology RA. In addition, both affect or thermostability. Dislocation density carbon trapping should be considered estimating yield strength two-step process. V Nb-Ti elements promote formation blocky Ti accelerates film-like For experimental with different processes compositions, true stress always keeps a linear relationship amount transformed martensite, i.e., 30.38~46.37 MPa per vol. 1% during deformation.