XLIX. Saturation moments and d-band configurations in iron and its alloys

Abstract

The saturation magnetic moments of certain iron alloys are difficult to interpret in terms of models found satisfactory for nickel alloys. It has been suggested that in pure iron the total number of empty d-band states is appreciably greater than the number of unpaired spins calculated from the saturation moment. The saturation moments of some iron-cobalt-aluminium alloys have therefore been measured and the effect of aluminium on the moments of iron-cobalt alloys is compared with its effect on the moment of pure iron. It is concluded that in iron the number of empty d-states exceeds the number of unpaired spins; the latter quantity is 2·22 per atom, while the value suggested for the former is greater than 3 per atom. The details of the effects found in the ternary alloys are discussed in terms of the d-band shape.