Influence of Ba Substitutions on Microstructure and Magnetic Properties of La–Ca–Co System Permanent Ferrite

Journal Article · Wed May 15 04:00:00 EDT 2019 · Journal of Superconductivity and Novel Magnetism

DOI:https://doi.org/10.1007/S10948-018-4796-3· OSTI ID:22921305

Zhou, X. W.; Geng, Z. W.; Zhu, D. M.; Jia, L. Y.; Wang, Q.; Huang, K. M.; Xiong, J.; Hu, G. H.; Li, B. S. ^[1]

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1. BGRIMM, National Engineering Technology Research Center for Magnetic Materials (China)

La{sub 0.6}Ca{sub 0.4−x}Ba{sub x}O⋅n/2(Fe{sub 1−y}Co{sub y}){sub 2}O{sub 3}(x = 0, 0.05, 0.1, 0.15 and 0.2) permanent ferrite materials were prepared by ceramic technique. The topography and the structure were characterized by scanning electron microscopy (SEM) and x-ray diffraction (XRD), respectively. The magnetic properties were measured using vibrating sample magnetometer (VSM) and digital magnetometer. Single M-phase and flake-like grains were obtained for samples without Ba substitution(x = 0), and the magnetic properties of the pre-sintering La–Ca–Co ferrite were as follows: B{sub r} = 440 mT, H{sub cb} = 296 kA/m, H{sub cj} = 426 kA/m, (BH){sub max} = 36.6 kJ/m{sup 3} and H{sub k}/H{sub cj} = 0.83. When Ca was substituted by Ba, pre-sintered powder presents single M-phase structure and close three-dimensional size of grains, resulting in an improved rectangle ratio of sintered magnet. The rectangle ratio of sintered magnet reaches a maximum of 0.93 when x = 0.1. By optimizing process parameters, M-type La–Ca–Ba–Co sintered magnet was prepared with B{sub r} = 445 mT, H{sub cb} = 337 kA/m, H{sub cj} = 420 kA/m, (BH){sub max} = 38.6 kJ/m{sup 3} and H{sub k}/H{sub cj} = 0.95.

• OSTI ID: 22921305
• Journal Information: Journal of Superconductivity and Novel Magnetism, Journal Name: Journal of Superconductivity and Novel Magnetism Journal Issue: 5 Vol. 32; ISSN 1557-1939
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM ADDITIONS
CALCIUM COMPOUNDS
CERAMICS
COBALT COMPOUNDS
FERRITES
LANTHANUM COMPOUNDS
MAGNETIC PROPERTIES
MAGNETS
MICROSTRUCTURE
OPTIMIZATION
SCANNING ELECTRON MICROSCOPY
SINTERING
THREE-DIMENSIONAL LATTICES
VIBRATING SAMPLE MAGNETOMETERS
X-RAY DIFFRACTION