STRUCTURAL, THERMAL, AND RADIATION INDUCED DEFECTS IN NiAl

B. Logar1, W. Puff1, S. Brunner1, A. G. Balogh2, H. Baumann3

1 Institut fuer Kernphysik, Technische Universitaet Graz, Petersgasse 16, Graz, Austria,
2 FB Materialwissenschaft, Technische Hochschule Darmstadt, Darmstadt, Deutschland,
3 Institut fuer Kernphysik, J.W. Goethe Universitaet Frankfurt am Main, Deutschland

In this contribution we report first results of our recent studies of defects in NiAl in the composition range 47 at.% < CNi < 53 at.%. Positron annihilation experiments were performed on samples slowly cooled, quenched or irradiated with protons. The combined positron lifetime and Doppler broadening data show the coexistence of different vacancy-type defects.