Magnetic Properties of Manganese Copper Alloys

Abstract

The magnetic properties of the manganese-copper alloy system have been investigated by using a numberof experimental techniques. Long range antiferromagnetic order occurs in alloys of high manganese concentration;the disappearance of ordering is associated with a face centered tetragonal → face centeredcubic martensitic transformation. By extrapolation of the experimental results it is possible to derive theNéel temperature and magnetic moment of manganese ions in pure fct γ-manganese as approximately390°K and 2.4±0.1 μ B , respectively. At lower manganese concentrations, it is likely that short range antiferromagneticordering occurs and in addition at sufficiently low temperatures weak ferromagnetic behaviorassociated with high coercive force becomes apparent. These results and possible interpretations of themare discussed.