Phase Stability and Magnetic Transition of Fe-Ni Alloys Prepared by Mechanical Alloying

Phase stability of FexNi1-x alloys (x=0.65~x=0.90) prepared by milling was investigated, together with the magnetic transition of the FCC phase. In as-milling state the BCC single phase was obtained in x=0.84 and higher Fe samples, and the FCC single phase in x=0.65. Between these two compositions, FCC and BCC mixed phase appeared. After the heat treatment at 1073 K for 300 sec, the FCC single phase was obtained in x≦0.84 and the BCC and FCC mixed phase in x=0.85 and 0.88. The BCC-FCC phase transformation temperatures both for heating and cooling rose with Fe concentration. It was shown that the Curie temperature of the FCC phase decreased with Fe concentration.