Magnetic properties of Sr1-xGdxFe12-xCoxO19 (0 ≤ x ≤ 0,5) hexaferrites

Abstract

Sr_1-xGd_xFe_12-xCo_xO₁₉ ( x = 0; 0.1; 0.2; 0.3; 0.4; 0.5) ferrites have been prepared by solid-state method under air at 1473 K. It has been found that increasing the value of x first leads to a slight decrease in the Curie temperature, from 727 K for the base ferrite SrFe₁₂O₁₉ to 725 K of solid solution Sr_0.9Gd_0.1Fe_11.9Co_0.1O₁₉, but with x further increasing, the Curie temperature rises reaching 745 K at x=0.5. It has been found that at 5 K and 300 K, spontaneous magnetization (n_o) values are respectively 4.2 and 3.7 % higher for solid solution Sr_0.9Gd_0.1Fe_11.9Co_0.1O₁₉ than for the base ferrite SrFe₁₂O₁₉.