Abstract :
Particle properties i.e., particle diameter, thickness, aspect ratio(diameter/thickness), particle size distribution etc., are important factors governing barium ferrite medium properties and performance. The effects of aspect ratio on saturation magnetization, coercivity, output level, orientability etc. are discussed. Wavelength response for barium ferrite media were investigated, assuming log-normal particle size distribution. Smaller particles with narrower distribution are important for obtaining better short wavelength response and better signal to noise ratio. If aspect ratio is kept constant, an optimum particle diameter exists for maximizing the output at a given wavelength. By comparing perpendicularly, longitudinally and randomly oriented media, perpendicular orientation was found to be prominent in obtaining higher output at submicron wavelengths. Test results show that barium ferrite media are free from corrosion and pressure induced demagnetization. Some barium ferrite media application aspects are also discussed.
