Tribological Evaluation of Coatings in Fuel Environments

Abstract To enhance the durability and reliability of high-pressure fuel system components operating with low-viscosity fuels, an analysis of the tribological performance of potential coating material candidates was conducted. This study focuses on evaluating the friction and wear characteristics of various coatings widely used by industry for surface protection, including carbides, nitrides, diamond-like carbon (DLC), and solid lubricants, under accelerated reciprocating ball on flat conditions intended to provide information on longer-term operation in fuel pumps. The tribological performance of these coatings in fuels of varying chemistry and viscosity, including ethanol, decane, dodecane, and aviation fuel (F-24), was compared to the mechanical properties of materials, such as hardness and elastic modulus. Results indicate that carbides show the lowest friction and wear values across different fuel environments. CrN-based coatings demonstrate a decrease in friction and wear in comparison to other nitrides. This comprehensive investigation lays the groundwork for informed design decisions in developing high-performance coatings tailored to withstand the challenges of low-viscosity fuel environments.