Magnetic properties of ferromagnetic shape memory alloys Ni2Mn1-xFexGa

Magnetic measurements on Ni2Mn1-xFexGa with 0 less than or equal to x less than or equal to 0.7 are made in the temperature range between 4.2 and 500K. A phase diagram of Ni2Mn1-xFexGa is determined from the results of the temperature dependence of the initial permeability. The Curie temperature T-C increases with the Fe concentration x and then makes a broad maximum around x = 0.6 on T-C versus x curve. The martensitic and reverse martensitic transformation temperatures decrease with increasing x. It is deduced that Fe atom in Ni2Mn1-xFexGa (0 less than or equal to x less than or equal to 0.7) has a large moment compared with that of pure a-Fe. (C) 2004 Elsevier B.V. All rights reserved.