Magnetoelastic Properties of Very Thin Co-Alloy Films

The magnetoelastic properties of thin longitudinal Co-alloy films were investigated by measuring the changes in the hysteresis loop during and after the application of a mechanical strain. Co, Co90Pt10, Co88Crl2. and Co78Pt10Crl2 thin films, ranging in thickness from 250 to 3000 Å were deposited on Mylar substrates and subjected to bending strains in the 10–3range. For all samples the coercivity, coercive squareness and remanent squareness decreased along the tensile axis, consistent with a negative magnetostriction constant. The magnetoelastic effects were found to scale approximately as He-1. The consequences of these observations for magnetic recording, in particular stress induced signal loss and transition broadening are discussed. © 1990 IEEE