Study of the lubricant properties of carbon nonfluoride: (CF subx) subn
Friction and wear tests were performed with rubbed carbon monofluorides derived from different types of carbon. Best results were given by fluorated artificial graphite and coke. The coefficient of friction is practically independent of the fluorine-to-carbon ratio x where 0 x 1, but wear decreases by a factor of 6 as x tends toward 1. For a range of variation of the severity factor (PV) expressed in Newtons/cm. sec (where P is the average pressure and V the velocity) contained between 1,000 and 200,000, the wear measured with carbon monofluoride is significantly lower than that obtained with MoS2. A transfer film or third body which protects the surfaces is formed with carbon monofluoride, and beyond 400 C, thick and fragile oxide coatings are also formed.