Microstructure characterization of nanocrystalline bainitic steel during tempering

High resolution transmission electron microscopy provided new experimental evidence on the carbide precipitation sequence, a subject critical to the understanding of the phase transformation mechanism during the tempering process in bainitic steel. The presence of high carbon transition carbides (η-carbides) is the result of the low amount of dislocation debris, which acts as effective carbon traps, near the blocky retained austenite.