Influence of Mn and Fe on Defects in NiAl Alloy Investigated by Positron Annihilation Techniques

摘要

Positron lifetime and Doppler broadening with a coincidence technique experiments have been performed in NiAl, Ni_(48)Al_(45)Mn_7, NI_(48)Al_(45)Fe_7 and Ni_(50)Al_(20)Fe_(30) polycrystalline alloys. It has been found that there are structural vacancies and large open-volume defects in binary NiAl alloy. The addition of Fe to MAl results in the decrease of the open volume of the defects and the concentration of structural vacancies. The effects of Mn and Fe on the distribution of electron momentum in the alloy have also been discussed.