WETTABILITY ASPECTS OF FRICTION AND WEAR REDUCTION BY A FLUORINATED SULFONAMIDE ADDITIVE IN A CHLOROTRIFLUOROETHYLENE-BASED FLUID

Chlorotrifluoroethylene (CTFE) is a non-flammable synthetic material d eveloped as a hydraulic fluid for Air Force systems. The sulphonamide additive is a low surface tension material with a complex molecular st ructure including several surface active groups. The addition of the s ulphonamide additive to the CTFE oil reduced wear on steel specimens b y helping in the formation of chemical reaction films on the surfaces. The physical aspects of how this additive helps in the formation of t he wear reducing films are discussed. There is evidence that the sulph onamide additive modifies the solid-liquid interface, preventing the s pread and loss of CTFE oil over a steel surface. By keeping the CTFE o il close to the interacting asperities, the sulphonamide additive cons erves the share of the load carried by the lubricant and makes the CTF E available for the formation of friction and wear reducing surface fi lms containing iron chloride and iron fluoride.