抄録
We propose a model of the bainitic transformation in the metastable phase quenched from a high temperature β phase region. The model is that the mechanism of bainite formation is essentially the same as that of the martensitic one. The metastable phase is inherently and strongly anharmonic, and it includes a large number of lattice defects. Such an anharmonicity instabilizes markedly some localized regions around special defects with intense [001] pressure toward the (110)[1\bar10] shear. As well as cooling and external stress, atomic diffusion will play a role of the trigger to enhance the [001] pressure, and finally the (110)[1\bar10] shear around the special defects will begin to occur. This is just the bainitic transformation. Composition change during ageing in the metastable phase is not a necessary condition of the bainitic transformation.
