Dislocation nucleation centers in the reverse α→γ martensitic transformation in iron alloys

Calculations for the elastic fields of the dislocations in the α-phase and some criteria derived from an analysis of the a α → γ martensitic transformation are used to select possible dislocation nucleation centers for the γ-phase. The main difference between the reverse transformation and the direct one is that in the former, the relationship between the nucleation center and the γ-phase crystals is not so definite, and, in particular, pairs of the γ-phase crystals prove to be associated with the same nucleation center. It is shown that the most probable nucleation centers may be the mixed dislocations along the α directions, with the {101} α glide planes, and the 1/2 α Burgers vectors