Structural transformation and magnetic properties of Sm-Fe alloys with V doping

A systematical investigation was carried out on structure and magnetic properties in SmFe_(9-x)V_(x)(x=0.4,0.8,1.2)compounds prepared by a single-roller quenching method.The high cool-down rate leads to metastable TbCu_(7) phase in the parent compound,which gradually transforms into equilibrium ThMn_(12) structure with V-doping content increasing.The Curie temperature increases from 470 to 590 K with V doping,which is consistent with the phase transformation.Surprisingly,simultaneous increase in both coercivity and remanence is resulted by V doping,reaching the highest value of 685 kA·m^(-1)and 44.8×10^(-3)A·m^(2)·g^(-1)in x=1.2 compound,respectively.This phenomenon can be explained by the combination of phase transformation and intergranular exchange coupling throughδM-H plots.