The process of martensite stabilization was investigated by applying resistometry and positron annihilation spectroscopy to alloys which exhibited the shape memory effect. A strong stabilization of martensite, which was observed in Cu-Al-Zn alloys, was explained by diffusion of the divacancies and monovacancies which were formed during quenching; with associated Arrhenius parameters of 6.4 x 108/s and 0.69eV for divacancies and 6 x 109/s and 0.84eV for monovacancies. It was found that the energy of vacancy formation in a Cu-8.5Al-14.5wt%Zn alloy was 0.56eV. The proposed model was confirmed by applying positron annihilation techniques. In the case of Cu-Al-Ni alloys, the disappearance of quenched-in vacancies was described by a single recovery process with a monovacancy diffusion energy of 0.74eV.

Analysis of Structural Defect Annealing in Copper-Based Alloys Exhibiting the Shape Memory Effect. B.Kostrubiec, J.Rasek, A.Salamon, H.Morawiec: Journal of Materials Science, 2002, 37[2], 369-73