Wear performance of electro-jet mask in-situ forming (CFx)n/CaF2-ZrO2/TiO2 composite films

Abstract

In this paper, the electrojet mask in-situ forming technology was used to prepare (CF_x)_n/CaF₂-ZrO₂/TiO₂ composite films with different ZrO₂/TiO₂ texture distributions, to improve the adhesion properties and tribological performance of (CF_x)_n/CaF₂ lubricant films. The microstructure, mechanical properties, and reciprocating wear characteristics between the composite films and 304 stainless steel counterparts were studied. The results showed that the textured hard film significantly improved the adhesion strength of the soft film and the tribological properties of the composite film. The composite film sample B had the lowest friction coefficient (∼0.100) and a lower film wear rate of ∼2.85 × 10⁻⁷ mm³ N⁻¹ mm⁻¹, and also showed good self-lubricating properties in the high-temperature wear process. Sample C had a lower friction coefficient of ∼0.107 and the lowest film wear rate of ∼2.75 × 10⁻⁷ mm³ N⁻¹ mm⁻¹. Compared with untextured composite film sample DC, sample B showed a 21.3 % reduction in friction coefficient, while sample C showed a 54.8 % decrease in film wear rate. This was because the surface texturing treatment of hard films enhanced the storage and flow of lubricant particles, and maintained a stable self-lubricating film during reciprocating wear. Moreover, (CF_x)_n and CaF₂ have a synergistic effect in a wide temperature range of 25 °C–600 °C.