Magnetostructural transition in NiCuCoMnGa alloys

The effects of the addition of Co on the martensitic transformation and Curie transition temperatures of polycrystalline Ni_46-xCu₄Co_xMn_33.5Ga_16.5 (x=0, 1, 3, 5) alloys are investigated. An abrupt decrease in the martensitic transformation temperature and an obvious increase in the Curie transition temperature of austenite (T_C^A) are observed when Co is doped in the NiCuMnGa alloy. As a result, the composition range for obtaining the magnetostructural transition is extended. Furthermore, the effect of a strong magnetic field on the magnetostructural transition is analyzed. This study offers a possible method to extend the composition range for obtaining magnetostructural transition in Heusler alloys.