The purpose of this paper is to investigate the tribological properties of Si3N4 sliding against Dy−sialon ceramics lubricated by two novel phosphazenes bridged fluorophenoxycyclotriphosphazene (coded as L‐2P) and metal halide‐stabilized linear phosphazene derivatives (coded as LMZn‐3). The traditional phosphazene tetrakis (3‐trifluoromethylphenoxy)‐bis(4‐fluorophenoxy) – cyclotriphosphazene (X‐1P) was also tested as the reference.
The lubricity characteristics of phosphazene derivatives were evaluated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn sialon surface was analyzed with a scanning electron microscope (SEM) and X‐ray photoelectron spectroscope (XPS).
The two novel phosphazenes are effective lubricants for Dy−sialon and show superior tribological properties to traditional phosphazene X‐1P and glycerol. Among all lubricants, linear phosphazene LMZn‐3 exhibits the lowest wear volume loss at 20°C or 100°C. Moreover, LMZn‐3 and L‐2P show much better antiwear ability than X‐1P under higher load than 60N. The decreased friction coefficient and wear volume of Dy−sialon ceramics under lubrication of the phosphazene lubricants are attributed to the tribochemical products mainly consisting of organic oxyfluoride or carbonfluoride species and silicon fluoride.
The paper deals with only limited compounds. The paper works on the subject progressively to explore more combinations for better tribological properties.
The phosphazene derivatives present better tribological performance used as base oils and additives.
There are few data about other phosphazene with different structures, such as bridged cyclotriphosphazene and metal halide‐stabilized linear phosphazene, used as lubricants for ceramics materials.
