Title :
Hexagonal ferrite particles for perpendicular recording prepared by ion exchange
Author :
Samaras, D. ; Georgiou, J. ; Panas, S. ; Litsardakis, G.
Author_Institution :
Aristotelian Univ., Thessaloniki, Greece
fDate :
1/1/1990 12:00:00 AM
Abstract :
Particles of nonstoichiometric M-type barium hexaferrite with the chemical formula BaFe10.5M0.25O17.05 (M=Mg, Cd, Co, Ni, Nd Zn) have been prepared by ion exchange in Ba containing molten salts from precursor ferrites with the β- or β"-alumina structure. The particles possess a plateletlike shape with diameters as low as 0.2 μm and as diameter-to-thickness ratio between 5 and 10. The Curie temperature is close to 470°C. Saturation magnetization values σs up to 64 emu g and coercive fields jHc ranging from 0.5 to 1.5 kOe were found
Keywords :
Curie temperature; barium compounds; ceramics; coercive force; ferrites; ion exchange; magnetic properties of fine particles; magnetisation; particle size; powder technology; BaFe10.5Cd0.25O17.05; BaFe10.5Co0.25O17.05; BaFe10.5Mg0.25O17.05; BaFe10.5Ni0.25O17.05; BaFe10.5Zn0.25O17.05; Curie temperature; M-type hexaferrite; coercive fields; diameter-to-thickness ratio; hexagonal ferrite particles; ion exchange; nonstoichiometric; perpendicular recording; plateletlike shape; saturation magnetisation; Anisotropic magnetoresistance; Barium; Chemical engineering; Ferrites; Magnetic anisotropy; Perpendicular magnetic anisotropy; Perpendicular magnetic recording; Saturation magnetization; Temperature; Zinc;
Journal_Title :
Magnetics, IEEE Transactions on
