Strong ferromagnetism in Invar type Fe-Pt alloys

Abstract

The magnetisation and Mossbauer effect have been measured for the Invar type FCC Fe-Pt alloys. The atomic moment of the alloys varies linearly with concentration, following the Slater-Pauling curve, which indicates that the iron atom possesses a full moment of 2.7 mu _B even in the Invar region. The hyperfine field acting on the Fe nucleus in these alloys is independent of concentration. These results imply that the Fe-Pt Invar alloys are strong ferromagnets, i.e., weak itinerant ferromagnetism is not responsible for the Invar properties of Fe-Pt alloys, in contrast to the Fe-Ni Invar alloys.