A Study of Structure of Metastable Cu–Zn Alloys with Shape Memory Effect

Methods of transmission and scanning electron microscopy are used to study premartenstic states and their relation to martensitic transformations in the alloys Cu–38 wt % Zn and Cu–39.5 wt % Zn with shape memory effect. Analysis of the observed diffusion scattering of electrons is carried out, including in situ experiments at heating and cooling and the defect condition of the internal substructure of austenite and martensite. The crystallographic models of martensitic transitions β₂ → \(\beta _{2}^{'}\) , β₂ → \(\beta _{2}^{{''}}\) , and β₂ → \(\gamma _{2}^{'}\) are proposed based on the crystallographic data obtained in the premartensitic state.