Synthesis and magnetic properties of hard magnetic (CoFe2O4)–soft magnetic (Fe3O4) nano-composite ceramics by SPS technology

Composition dependence of the magnetic properties of CoFe2O4/CoFe2 composite nano-ceramics

“…Since the concept of the ES effect was introduced in 1991 [2], many types of ES magnets, including films and ceramics, have been synthesized, including Nd-Fe-B/Fe-B [2], CoFe 2 O 4 / Fe 3 O 4 [4,5], Ba-ferrite/Ni 0.8 Zn 0.2 Fe 2 O 4 [6], Ba-ferrite/Fe 3 O 4 [7], and FePt/Fe [8][9][10]. In recent years, CoFe 2 O 4 /CoFe 2 , a new type of ES magnet, has attracted attention because it can be easily prepared by reducing CoFe 2 O 4 [11][12][13][14][15][16].…”

Alloying of Fe3O4 and Co3O4 to develop Co3xFe3(1−x)O4 ferrite with high magnetic squareness, tunable ferromagnetic parameters, and exchange bias

“…Liu et al [14] found the highest value of H C $ 1.85 kOe and M sat $ 23.4 emu/g in the nanocomposite of CoFe 2 O 4 (FM) and BiFeO 3 (AFM). Fei et al [15] used CoFe 2 O 4 as hard magnet and Fe 3 O 4 as the soft magnet to form a composite magnet by mechanical milling. They were able to tailor the FM parameters at 10 K in a wide range (H C $ 1-4 kOe, SQ $ 0.35-0.85, and M sat $ 80-130 emu/g) by varying the sintering temperature of the composite at P500°C.…”

Synthesis of nanostructured iron oxides and new magnetic ceramics using sol-gel and SPS techniques

“…However, there are a number of complications in using ceramic materials, connected, firstly, with phase and structural heterogeneities of obtained ceramics. Magnetic properties of the composites are structural-dependent [7,8] and are defined not only by phase-composition of the composite, but also by size, shape of the crystallite and pores. These parameters can organize/distort magnetic anisotropy, cause/eliminate elastic strains, and consequently influence on magnetic characteristics [9].…”

“…Great number of researchers admit viability of implementation of SPS technology for consolidation of nanostructured powders into dense ceramic compounds [18,19], also for creating of highly magnetic nanoceramics [7,8]. Consolidation of nan disperse magnetic powders by electric current under optimally chosen regimes of heating and mechanical load enables one to obtain materials of high quality with predetermined and also reproducible phase and structural characteristics.…”