Magnetic Contributions to the Elastic Constants of Nickel and an Fe-30% Ni Alloy at High Magnetic Fields

Abstract

The possibility that the fundamental interatomic magnetic infraction makes an observable contribution to the elastic constants of a ferromagnetic metal has been investigated experimentally in nickel and an Fe‐30% Ni alloy. The effects of a noncentral interaction were found to be too small to be observed or were masked by effects arising from magnetization direction changes induced by the measurement process. The central force part of the interaction which should produce changes in the elastic constants upon passing through the Curie temperature was clearly observed in both nickel and the Fe‐30% Ni alloy. The interpretation of these results in terms of the magnetic exchange energy is straightforward for nickel but the large volume magnetostriction in the Fe‐Ni alloy makes the analysis of the data difficult.