Friction Characteristics of Vapor Deposited Lubricant Films 890148
Lubricating films were deposited on friction test specimens from a homogeneous gas phase mixture of nitrogen and various lubricant vapors. The lubricants used were tributylphosphate ester (TBP), tricresylphosphate ester (TCP), trimethylolpropane-triheptanoate ester (TMPTH) and mix-bis-(m-phenoxyphenoxy)benzene (PPE). The volume percent of lubricant vapor in nitrogen ranged from 0.5 to 3.0 percent. The friction tests were performed over a temperature range of 245 to 586°C. The lubrication properties of vapor deposited films were found to be controlled by the specimen temperature, vapor exposure time, lubricant vapor concentration and lubricant chemistry. Lubrication of the tribocontact can be optimized by using the deposition parameters to give the optimum film thickness for a given lubricant.