Friction/stiction and wear studies of magnetic thin-film disks with two polar perfluoropolyether lubricants

Polar and nonpolar perfluoropolyether (PFPE) lubricants are almost exclusively used for topical lubrication of magnetic thin-film disks. However, little is known about the effects of degree of chemical bonding and chemical structure of the lubricant and the operating environment on the tribological performance of head-disk interface. In this study, thin-film disks were lubricated with two different polar PFPE lubricants. Static and kinetic friction, long-term (rest) stiction and durability were measured using a single-disk tester at different relative humidities to investigate the effects of chemical structure and chemical bonding of lubricant and humidity on the tribological performance of head-disk interface. Experimental results show that friction and stiction are strongly affected by humidity as well as the rest time of the head slider on the disk at a given roughness and lubricant film thickness. Stiction of one of the lubricant studied here is somewhat insensitive to high humidity. Chemical bonding of the lubricant is shown to improve the friction/stiction performance with some reduction in the durability.