The effect of process solvent and moisture level on lubricant film property and its performance

Summary form only given. Several types of fluorinated solvents can be used for dip-coating of lubricant films. The different solvents´ ability to dissolve other chemical species, especially water, has been raised as a concern. Discussion is on whether the solvent strength is beneficial or detrimental to the behavior of the lubricant and/or the additive. In this experiment a four-factor matrix was conducted to study: (a) PFPE lubricants, Z-Dol and AN3001, (b) the presence of X-1P additive, (c) a perfluorocarbon solvent, having low water solubility, and a hydrofluoroether solvent, having significantly higher water solubility, and (d) relatively dry solvents compared with ones purposely saturated with water. Lubricant bonding ratio (LBR), X-1P bonding ratio (XBR) and water contact angle (WCA) measurements were used to characterize the lubricant films, at both short and long times after lubricant application. Constant start-stop (CSS) tests were used to evaluate the tribological performance of these films.