Chemical composition and coercivity of SmCo5 magnets

作者: M. F. de Campos , F. J. G. Landgraf , N. H. Saito , S. A. Romero , A. C. Neiva

DOI: 10.1063/1.368075

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摘要: The effects of alloy composition and heat treatment on the intrinsic coercivity iHc SmCo5 magnets were studied. Alloys having six chemical compositions near that stoichiometric used to produce via usual powder metallurgy techniques. Magnets either as sintered (1150 °C) or treated at 850 °C. substantial increase in due 850 °C occurs reversibly with a negligible change lattice parameters, Curie temperature Tc anisotropy field HA. Quantitative metallography thermomagnetic measurements showed microstructural constituent present addition phase hyperstoichiometric alloys is composed both Sm2Co7 Sm5Co19 phase. Measurements magnetization dc magnetic fields up 33 T suggest HA around 53 T, considerably higher than previously reported values. discussed terms thermal equilibrium populations defects.

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