MAGNETIC-PROPERTIES OF MECHANICALLY ALLOYED FE-CU

Magnetic properties of equiatomic FeCu alloys, obtained by mechanical alloying, were measured in a temperature range between 5 and 300K. The as-milled sample consists of a metastable fcc FeCu phase with a tempe rature dependence of magnetization which follows a T3/2 law. This meta stable phase decomposes into Cu and Fe phases with annealing. After an nealing at 820K, the magnetization value at low temperature is 30% sma ller than the unannealed state. The Mossbauer spectrum obtained at roo m temperature shows a paramagnetic Fe phase with a relative resonant a rea of 30%. These results suggest that after this annealing process 30 % of the iron is not in the ferromagnetic alpha phase but in a non-mag netic state (with vanishing atomic magnetic moment) or probably formin g an antiferromagnetic gamma-Fe phase (which is paramagnetic at room t emperature).