On the Forced Magnetostriction of Fe-Ni Invar Alloys at 4.2°K

Transverse and longitudinal forced magnetostrictions of Fe-Ni Invar alloys were measured by means of the paper strain gauge technique at room temperature, 77° and 4.2°K. From the measured values of the forced magneto-strictions, the pressure coefficients of the absolute saturation magnetization were estimated. The absolute values of the pressure coefficients of the absolute saturation magnetization were found to decrease monotonically with an increase of Ni concentration. On the basis of Sidorov's theory the pressure effect on the absolute saturation magnetization is discussed.