HUMIDITY EFFECT ON FRICTION STICTION AND DURABILITY OF HEAD-DISK INTERFACE WITH POLAR PERFLUOROPOLYETHER LUBRICANT/

Drag and contact start and stop (CSS) tests are performed at different relative humidities to understand the effect of humidity on friction/ stiction and durability of thin-film disks lubricated with a polar per fluoropolyether lubricant. Coefficient of friction and stiction increa ses above a certain relative humidity (RH), Durability increases with an increase of relative humidity and then decreases with a further inc rease of humidity after having reached a maximum. Humidity effect on f riction/stiction and durability is found most severe at about 80% RH. Adsorbed water may displace and/or permeate into the lubricant film an d result in a nonuniform liquid film. (C) 1997 American institute of P hysics.