Preparation and magnetic properties of anodic oxide magnetic films

Abstract

AbstractThe M‐H curve, coercive force and magnetic anisotropy of magnetic anodic oxide films containing electro‐deposited iron particles in pores were measured for the various pore diameters between 150 and 1200 Å, packing densities between 0.13 ‐ 0.48 and film thicknesses between 0.08 and 1.3 μm. As a result, it was found that the coercive force perpendicular to the film surface depends only on the pore diameter when the length of the iron particle is 15 times larger than its diameter, and that it decreases in inverse proportion to the square of the pore diameter when the pore diameter is larger than 350 Å. This indicates that the mechanism of magnetization reversal in these films follows the curling mode. The coercive force parallel to the film surface is affected by the shape of the initially deposited iron particles. The magnetic anisotropy depends strongly on the packing density of the iron particles. When the packing density is less than 0.32, the direction perpendicular to the film surface is the direction of easy magnetization. When the packing density is higher than 0.32, the direction parallel to the film surface is the direction of easy magnetization.