WEAR RESISTANCE AND MECHANICAL PROPERTIES OF SANDWICH-LIKE NANOSTRUCTURED COMPOSITES AND APPLICATION IN FUEL CONTAINERS

摘要

A new aluminum oxide-chromium carbide-based composite coating has been developed for practical application in aerospace/automotive fuel tanks. The protective sandwich-like composite coating has perfect combination of thermal/mechanical and tribological properties over a wide temperature range. Pyrolitic deposition of CrC layer was used to mechanically/thermally strength aluminum oxide layer formed on aluminum/polymer-based substrate of fuel tank. CrC layer has strengthened aluminum oxide layer by filing surface defects and pores. Friction and wear rate were determined using a pin on disk tribometer at 25-900°C temperatures in hydrogen, helium, and air. Pin materials included several metallic alloys and silicon carbide. It was revealed that appropriate additions of disulfide molybdenum, or diamond nanoparticles to the baseline composition significantly reduced friction coefficients while preserving, and in some cases, even enhancing wear resistance. The results of this study demonstrate that the composite is a promising coating composition to consider for high-temperature and/or cryogenic aerospace and advanced fuel tank applications. The excellent results in hydrogen make this composite coating of particular interest for use in automotive fuel tanks. Based upon observed tribological mechanics model has been proposed to describe thermal/mechanical behavior of the composite coating.