MAGNETIC PROPERTIES OF NICKEL-COPPER AND NICKEL-COBALT ALLOYS

This paper reports on the effects of alloy composition and applied stress on the magnetic properties of nickel, nickel-copper and nickel-cobalt alloys. The reduction in saturation magnetization on addition of copper to nickel was greater than expected on the basis of a simple rigid band approximation, however the effects of adding cobalt to nickel were very close to expectations. The saturation magnetostriction λs of the copper-nickel alloys was reduced by the addition of copper, however the rate of change of magnetostriction with magnetization, dλ/dM was increased on addition of copper. The change in anhysteretic and maximum differential susceptibility with stress was found to be consistent with recent theoretical models only at stress amplitudes below 25 MPa