The bainitic mechanism of austenite formation during rapid heating
- Univ. du Littoral Cote d`Opal, Longuenesse (France). Lab. d`Applications en Genie Industriel-Energie-Environnement
- Univ. de Lille 1, Villeneuve d`Ascq (France)
Strips of a spheroidized 0.68% C, 0.67% Mn and 0.24% Si pearlitic steel were submitted to rapid heat cycles. The samples were heated by direct electrical conduction up to a peak temperature and immediately water quenched. The morphological features of the {alpha} {r_arrow} {gamma} transformation were studied by light and electron microscopy. It was found that austenite at an early stage of the transformation has a specific lath-like morphology and that its growth always starts directly from a grain boundary of ferrite. Moreover, the presence of retained austenite allows the prediction of relatively high carbon content in the transformation product. The particular interaction of austenite laths with carbide particles gives an indication that the growth mechanism can be displacive at its early stage. Comparing the morphological characteristics of austenite formation observed in this study with those reported for austenite decomposition, a bainitic model of the early stage of {alpha} {r_arrow} {gamma} transformation is proposed.
- OSTI ID:
- 289503
- Journal Information:
- Acta Materialia, Vol. 46, Issue 16; Other Information: PBD: 9 Oct 1998
- Country of Publication:
- United States
- Language:
- English
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