Synthesis and properties of composite magnetic material SrCoxFe12-xO19 (x=0–0.3)

Preparation and Magnetic Properties of Nd–Co-Substituted M-Type Strontium Ferrite by Microwave-Assisted Synthesis Method

“…4 The hysteresis loops of SrFe 11.95 Co 0.05 O 19 at room temperature with different calcination temperatures of coercivity (H c ). Xie has figured out that the Co 2+ ions replaced by Fe 3+ ions occupy the octahedral 4f 2 and 2a sites in strontium hexaferrites structure [8]. For microwaveassisted calcinations, electromagnetic waves directly interact with the material at a molecular level via dipolar interactions, which decreases the sintering activation energy significantly and promotes the diffusion of ions [18,19].…”

“…In our work, the maximum value of coercivity is received in samples calcined at 1050 • C. The enhancement of coercivity at high calcination temperature could be attributed to two aspects: the enhancement of anisotropy field for the substitution of Fe 3+ ions by Co 2+ ions and the formation of grains with plate-like shape. The M-strontium hexaferrites with grains in plate-like shape have higher morphology anisotropy [8] and are beneficial to coercivity [22]. To modify the magnetic properties of strontium ferrites, the co-substitution of Nd 3+ and Co 2+ ions was applied to replace the Sr 2+ and Fe 3+ ions, respectively.…”

“…The magnetization of strontium hexaferrite derives from the uncompleted offset of magnetic moment of Fe 3+ in different sublattices. The Co 2+ [8], Al 3+ [5], Cr 3+ [9], Pb 3+ [10], Zr-Zn [11], Nd-Co [12], and La-Al [13] substitution has caused various changes in the magnetic properties. In addition, the process of calcination has great relationship with the magnetic properties.…”

A novel ‘one-pot’ synthetic method for preparation of (Ni0.65Zn0.35Fe2O4)x–(BaFe12O19)1−x nanocomposites and study of their microwave absorption and magnetic properties

“…In comparison to the metallic systems, the nanocomposites composed of soft spinel ferrite and hard hexagonal ferrite have shown potential to be advanced permanent magnet, because of their low cost, excellent corrosion resistance behaviour and high electrical resistivity. However, reports on soft-hard ferrite nanocomposites in the literature are very limited [1,2,24,[32][33][34][35][36][37][38] From now onwards, nanocomposites prepared by one-pot method and physical mixing method will be referred as 'composites-OP' and 'composites-PM' respectively.…”

A novel method to fabricate CoFe2O4/SrFe12O19 composite ferrite nanofibers with enhanced exchange coupling effect

“…Among the hard ferrites, strontium hexaferrite (SrFe 12 O 19 ) has significant performances such as high Curie temperature ( T c ), high M s , high H c , large magnetocrystalline anisotropy ( H k ), and excellent chemical stability [15-17]. So far, the growing efforts have been devoted to the investigation of nanocomposites of CoFe 2 O 4 /SrFe 12 O 19 [18,19]. Nevertheless, these investigations indicated the presence of impurities such as α-Fe 2 O 3 [19,20], which exhibited a twisted hysteresis loop and an incomplete exchange coupling between the hard and soft phases [9,13].…”