SEM Studies of Wear Mechanisms in Magnetic Thin Film Disks With Different Overcoats

Scanning Electron Microscopy and optical profilometer studies were conducted to study the wear of unlubricated thin-film magnetic recording disks overcoated with carbon as well as silver and zirconia. The results indicate that wear of the carbon overcoat occurs in the form of localized damage, or “pits,” accompanied by a gradual “thinning” of the carbon overcoat in the wear track. A similar pitting behavior is found for zirconia overcoated disks, but the pits resemble cracks in the overcoat, while the wear of silver disks resembles that of typical metal-metal sliding interfaces.