Magnetic properties of Fe_3(1-x)Cr_3xC alloys

The magnetic properties of Fe_3(1-x)Cr_3xC alloys with x=0.05, 0.1, 0.15, and 0.2, which crystallize in the cementite Fe₃C-type structure with space group Pnma, were investigated by means of magnetization measurements. These alloys show temperature-induced second-order magnetic phase transitions. The Curie temperature (T_c) of these alloys decreases with increasing x. The isothermal magnetic-entropy changes of these alloys were derived from the magnetic isotherms measured with increasing temperature and increasing field. The maximum values of the magnetic-entropy change are about 0.9 and 3.6 J·kg^-1·K^-1 at T_c=360 K for x = 0.05 in a magnetic field change from 0 to 1 T and 0 to 5 T, respectively.