Zero to low magnetostriction, high coercivity, polycrystalline, Co-Pt magnetic recording media

摘要

An alloy of CoxPty with y between 10 and 30 at. % is made by sputtering with Hc>500 Oe and 4 pi Ms>5000 gauss, and zero magnetostriction. For 10 to 30 at. % Co the sputtered alloy has an Hc of 500-1000 Oe with 4 pi Ms of 4000-14000 gauss, a magnetostriction passing through zero between 20 and 30 at. % of Pt. For thickness below 1000 ANGSTROM Hc is large (for the above range of alloys) and magnetization is also larger and coercivity varies as a direct function of Pt composition in the alloy up to 30 at. %.