抄録
To improve the reliability of high-density magnetic systems, a new thin protective layer against wear and corrosion must be applied on magnetic disk media. Various low-energy beams produced from N2, O2, CF4 and CH4 plasma were irradiated onto Co-Cr-Ta magnetic media, and then the effects on hardness, corrosion resistance and magnetic coercive force were studied, and the following results were obtained. (1) To clarify the relationship between hardness and plasma state, plasma spectroscopy analysis was performed. The hardness was affected by ion and radical quantities in the plasma. (2) Various low energy beam irradiations increase the surface Vickers and nanoindentaion hardness. Especially, nitrogen and CF4 beam irradiations increase the hardness. The modulus of dissipation in deformation energy decreases with hardness increase. (3) Various low energy beam irradiations remarkably improve corrosion resistance evaluated from natural corrosion voltage in distilled water and physiological salt water solution. (4) Proper energy beam irradiation slightly degrades the magnetic coercive force of a magnetic disk.
