Studies of magnetic alloys by diffuse neutron scattering

Diffuse elastic unpolarized neutron scattering measurements have been used to investigate the magnetic behaviour of four transition metal alloy systems -weakly ferromagnetic PtCo and PtFe, NiRh (over the concentration range 4% to 24% Rh) and FeNi (over the Invar composition range). A general theory of the onset of magnetism in transition metal alloys has been proposed to account for the succession of magnetic states as the concentration of the magnetic components is increased. This is extended to a pure transition metal and an alternative interpretation of exchange enhancement is suggested. It is concluded that all transition metals are either magnetic or superconducting. (UK)