Measurements were made of positron annihilation lifetimes in polycrystalline icosahedral quasi-crystals. As-grown and plastically deformed single quasi-crystals of Al70.6Pd21.1Mn8.3 were also studied. In the case of every sample, it was found that the lifetime spectrum consisted of a single component with a lifetime of 206ps. This indicated that icosahedral quasi-crystalline Al-Pd-Mn contained a dense distribution of vacancy-type sites. These trapping sites seemed to remain unaltered during plastic deformation at high temperatures.

Positron Annihilation Study of Icosahedral AlPdMn Alloys I.Kanazawa, E.Hamada, T.Saeki, K.Sato, M.Nakata, S.Takeuchi, M.Wollgarten: Physical Review Letters, 1997, 79[12], 2269-72