Concentration dependence of magnetic moment in Ni_50-x Co _x Mn_50-y Z_y (Z=In,Sn) Heusler alloys

The concentration dependence of magnetic properties in the austenite phase of NiCoMnIn and NiCoMnSn Heusler alloys was systematically investigated by the magnetization measurements. The T_C for Ni_(50-x) Co _x Mn_(50-y) Sn_y alloys linearly increases with increasing the Co content and fixed Sn content. Although showing a concave curve for Ni₅₀ Mn_(50-y) Sn_y ternary alloys, the Sn content-dependence of magnetic moment per formula unit changes from the concave curve to a straight line when Co is substituted for Ni. On the other hand, the In content-dependence of the magnetic moment for Ni₄₅ Co₅ Mn_(50-y) In_y alloys is perfectly linear as is that in the Ni₅₀ Mn_(50-y) In_y ternary alloys.