Charge transfer and martensitic nucleation

Summary The microscopic interpretation of phase stability in alloys undergoing thermoelastic martensitic transformation involves a difficult nucleation problem. The strong dependence of the critical temperature for the onset of martensite on composition requires the introduction of nonclassical defective nuclei, of dynamic nature, to obtain reasonable estimates of the energy barrier to nucleation. Experimental data on β-Au−Zn-based alloys are organized in the framework of the atomistic model of the valence electron localization degree. The resulting charge transfer scheme is strictly correlated to elementary surface segregation events driven by elemental surface energy differences within the studied alloys. The connection between martensitic nucleation and charge transfer segregation is discussed, focusing on the physical meaning of the various energy terms entering the model. To speed up publication, the author of this paper has agreed to not receive the proofs for correction.