Abstract
To compare the effects of anneal and UV irradiation, monolayer PFPE Zdol2000 films coated on magnetic disk surfaces were treated by anneal or UV irradiation, and then friction properties of the films were measured as functions of external load and sliding speed. In contrast to annealed films, UV-irradiated films exhibited noticeable fluctuations in friction during repeated measurements. We confirmed that the fluctuations, possibly caused by unstable contact state between a slider and UV-irradiated films, can be suppressed by high speed sliding. We also demonstrated that annealed PFPE films show strong dependence on sliding speed as compared with UV-irradiated films. Friction of annealed films was slightly smaller than that of UV-irradiated films at the low speed of 2.1 mm/s, but became significantly larger than that of UV-irradiated films at the high speed of 210 mm/s.
