MAGNETIC RECORDING MEDIUM

摘要

PURPOSE:To obtain a magnetic recording medium which deals with the higher recording density and has much excellent magnetic characteristics by successively forming an Mo layer and Co alloy magnetic layer on an aluminum alloy substrate having an aluminum oxide layer on the surface. CONSTITUTION:The Mo underlying layer preferentially orients the C axis of the h.c.p. structure of the Co alloy in the film plane and has, therefore, the effect of providing the magnetic layer in which the directions of easy magnetization are distributed in the surface. Thus magnetic layer contains <=35at% Ni or <=20at% Cr or <=45at% in total Ni and Cr. The compsns. of Ni and Cr is required not to exceed 35at% and 20at% respectively. The reason for limiting the contents lies in that the f.c.c. phase having no uniaxial anisotropy appears in the magnetic layer to deteriorate the magnetic characteristics if the contents exceed the specified numerical values. The h.c.p. phase having the uniaxial anisotropy is formed and the good magnetic characteristics are assured if the contents are within said range.