Tribological Coatings for Open Space

Abstract

This paper presents the results of tests of EPAN coatings, a composite material based on carbon–carbon fibers. It uses fine molybdenum disulfide as the main lubricant and for binders, phenol, peroxide, and silicone resins. The tests were carried out on microarc oxidation (MAO) coatings. For comparison, the tribological characteristics of EPAN under friction on steels, as well as molybdenum disulfide composites are given. The friction coefficients of EPAN coatings on MAO coatings according to the “shaft–bushing” scheme do not exceed 0.05 at pressures of 10–20 kg/cm² and shaft rotation speeds from 130 to 600 rpm. The advantage of such combinations of materials is the use of a light alloy, aluminum with MAO coating, for the counterbody to the EPAN coatings, which is important for space products. The creation and testing of solid lubricating coatings for modern space technology is a task of extreme importance, because in many developments of space products, low-temperature plastic lubricants continue to be used, which are operable up to subzero temperatures of –90 to –110°C. Such solutions require the use of thermal insulation and heating for mobile interfaces and friction units of machines, mechanisms, and devices. The result is a serious complication of structures and an increase in their weight. The tests of EPAN coatings on MAO coatings carried out in the work open new possibilities in the combination of materials for space technology. Having a coefficient of friction of 0.05 and high wear resistance, they allow you to create movable joints, first of all, sliding bearings, for operation on Earth sensing satellites, as well as mechanisms on the Moon.