2010 Volume 51 Issue 3 Pages 455-462
Atomic arrangement of bainite/austenite interface was examined by high resolution electron microscopy in a Fe-2Si-1.4C alloy. Lattice transition region with an intermediate lattice structure between two phases, which is a characteristic feature of shear-type deformation, was not observed either between upper bainite and austenite or between lower bainite and austenite. However, high density dislocations existed inside upper and lower bainites, which may be introduced as a result of lattice invariant shear deformation. Based on these experimental facts, the shear deformation assisted-diffusional transformation model was proposed for the bainitic transformation.