Order-disorder studies and magnetic properties of mechanically alloyed nanocrystalline Ni3Fe allay

Ni3Fe alloy with different grain sizes has been formed by mechanical alloying technique using a high energy ball mill. Fe-57 Mossbauer studies have been carried out at room temperature and hyperfine field distributions have been obtained for various milling durations. The influence of surface atoms on magnetic hyperfine fields and the effect af grain size an Fe magnetic moment have been investigated. The atomic ordering is found to be faster in the nanocrystalline form of Ni3Fe than in the bulk Ni3Fe. (C) 2001 Elsevier Science B.V. All rights reserved.