Magnetic anisotropy induced by cold rolling in Co and Co-Fe alloys

The roll reduction and concentration dependences of the uniaxial magnetic anisotropy induced by cold-rolling, K_ur, were investigated for hexagonal Co and Co-Fe alloys. The maximum value of K_ur was 3×10⁵ erg/cm³ at 10%-20% roll reduction for Co and Co-1.5% Fe. The easy direction was perpendicular and parallel to the rolling direction for the alloys containing less than 1.2% Fe and more than 1.2% Fe at room temperature, respectively. The easy direction of K_ur changed at 260 °C for Co. The texture produced by cold-rolling was detected by Schulz's method. The induced anisotropies were evaluated by using the K_u1, K_u2, and the x-ray reflected intensities. The calculated values and easy direction agreed well with the experimental results. The origin of K _ur for hexagonal Co and Co-Fe alloys is clearly explained by formation of rolling texture.