Magnetic texture and coercivity of anisotropic nanocrystalline SmCo 6.1Si0.9 magnets

Abstract

The magnetic texture and coercivity of anisotropic nanocrystalline SmCo6.1Si0.9 magnets prepared by surfactant-assisted high energy ball milling and spark plasma sintering have been investigated by verifying the processing parameters including surfactant's type, sintering temperature, and pressure. Surfactant, including oleic acid (OA) and oleylamine (OY), played a major role in enhancing the magnetic texture of the magnets because the flake morphology of the powder milled with surfactant favored the magnetic alignment. The magnets with OA had a little higher magnetic texture than that with OY, while the coercivity of the magnets with OA (4.2 kOe) was much lower than that with OY (7.7 kOe). Increasing sintering temperature or pressure resulted in a little decrease of magnetic texture, while improving the coercivity due to densification. And for the fully dense samples, the higher sintering temperature deteriorated the coercivity of the magnets resulting from grain growth. © 2014 AIP Publishing LLC.