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

• Published in: Ceramics international Vol. 41; no. 3; pp. 3896 - 3900
• Main Authors: Ou-Yang, Jun, Zhang, Yue, Luo, Xiaoning, Yan, Baiqian, Zhu, Benpeng, Yang, Xiaofei, Chen, Shi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2015
• Subjects: A: Sintering; B: Composites; C: Magnetic properties; Ceramics; D: Ferrites; Exchange; Information technology; Joining; Magnetic properties; Nanoparticles; Nanostructure; Phases; B: Composites; A: Sintering; D: Ferrites; C: Magnetic properties
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2014.11.071

CoFe2O4/CoFe2 composite nano-ceramics with varying composition ratios were synthesized using a reduction reaction and spark plasma sintering. The compositions and particle sizes of the ceramics were then characterized using X-ray diffraction, and the mass ratios were quantitatively determined via thermal-gravity analysis. The magnetic property characteristics indicate that the coercivity decreased significantly with an increase in the soft-magnetic CoFe2 content, while the saturation magnetization drastically increased. In addition, a characterization of the Henkel plots showed a clear enhancement of the inter-phase exchange coupling when the number of soft-magnetic CoFe2 nano-particles was increased. Enhanced exchange coupling at the interface between the soft-magnetic and the hard-magnetic phases is critical for the occurrence of exchange-spring behavior, which has potential applications in the field of information technology.