Abstract
We used a transparent pin-on-disk seek wear test to evaluate the effectiveness at reducing disk drive head wear of several perfluoropolyether lubricants with different end-groups, under various heat and UV irradiation conditions. The extent of Pin wear decreased as bonding ratio increased, with a wear minimum between 30 and 40% bonding ratio on UV irradiated Fomblin Z-dol or Phospharol A20H lubricants. A further wear minimum occurred at higher bonding ratios on both lubricants. Pin wear amounts on disks with heat treated lubricants were different from those on disks with UV irradiated lubricants. Disk failure occurred on disks with UV irradiated Fombrin Z-dol lubricant of high bonding ratio. Sliding conditions during wear tests were also recorded and investigated, showing changes in the lubricant picked-up on pin surfaces - at low bonding ratio disks, this was liquid-like whereas at medium to high bonding ratio disks it became gel-like. On UV irradiated high bonding ratio disks, black powdery debris were found. The mimima in wear found on UV irradiated Z-dol and A-20H lubricated disk seemed to be affected by the amount of debris under the pins. Changes in lubricant rheological properties by UV irradiation or heat treatment should be studied further.
