The Effect of Dy-Additive on Phase Transformation and Magnetic Properties of Fe-Pt Alloy Films

A series of Fe-Pt based alloy films were deposited on glass substrates by DC magnetron sputtering. It is found that the Fe3Pt and FePt3 phases appear in Dy-addition films at first and then a composition reaction Fe3Pt + FePt3 FePt occurs at 500°C as annealing time increase. It suggested that Dy element can restrain the fct phase forming but help to form Fe3Pt and FePt3 phases. Coercivity and remanence ratio of DyxFe50-xPt50 alloy films annealed at 500°C for 200 h achieve the maximum 11kOe and 0.89 as x =1.5, respectively.