Title :
Magnetic properties of Sr-La system M-type ferrite fine particles prepared by controlling the chemical coprecipitation method
Author :
Yamamoto, Hiroshi ; Seki, Hirota
Author_Institution :
Sch. of Sci. & Technol., Meiji Univ., Kawasaki, Japan
fDate :
9/1/1999 12:00:00 AM
Abstract :
Single phase Sr-La M-type ferrite fine particles were prepared by the chemical coprecipitation and subsequent heat treatment methods. Optimum magnetic properties were achieved with materials of composition Sr0.7942+La0.1723+Fe 0.3352+Fe11 .743+O19, and heat treatment of 950°C×2 h in air, The magnetic and physical properties are σs=90.5×10-6 Wb·m/kg (72,0 emu/g), HcJ=505.3 kA/m (6.35 kOe), Tc=454.4°C, the lattice constants a=0.5882 nm, c=2.303 nm, the activation energy=230.9 kJ/mol (55.2 kcal/mol), and the average particle size=0.3 μm
Keywords :
Curie temperature; ferrites; heat treatment; lanthanum compounds; lattice constants; magnetic particles; materials preparation; particle size; precipitation (physical chemistry); strontium compounds; (SrLa)Fe12O19; 0.3 mum; 2 h; 454.4 degC; 950 degC; Curie temperature; Sr-La system M-type ferrite; Sr0.7942+La0.1723+Fe 0.3352+Fe11 .743+O19; activation energy; average particle size; chemical coprecipitation; fine particles; heat treatment; lattice constants; magnetic properties; physical properties; single phase; Chemical technology; Control systems; Ferrites; Heat treatment; Magnetic field measurement; Magnetic properties; Particle measurements; Saturation magnetization; Temperature; Vibration measurement;
Journal_Title :
Magnetics, IEEE Transactions on
