The effect of indium–tin oxide coatings on the formation of craters on glass surfaces under the impact of high-velocity microparticles

Abstract

This article considers the problem of improved mechanical properties and protection of glass materials in optical systems of space vehicles. One the possible methods to solve the problem is the formation of multi-phase nanocomposite shock-resistant transparent coatings on the surface of glass plates. Considerable attention is paid to the application of indium–tin oxide (ITO) coatings on the surface of quartz glass pieces deposited by the method of pulsed magnetron sputtering. Such coatings demonstrate the highest properties. The optical characteristics of ITO coatings were studied in a range of wavelengths of 200–1100 nm. It was shown that in the visible spectrum they remain transparent. The structure and phase composition of indium tin oxide coating, basically, contains nanocrystalline In2O3 phase, which is indicated by the diffraction reflexes on obtained electron diffraction patterns and X-ray diagrams.It was unveiled that the deposited ITO-based coatings possess resistance to the shock impact of hyper-velocity iron microparticles. They can appreciably reduce surface density of the craters formed on the surface of glass plates under the impacts of solid microparticles due to increased strength and cracking resistance of the glass specimens. The character of alteration of the crater density of the glass surface with the coating is explained by the superposition of two mechanisms: reinforcement of the surface layer of glass due to deposited nanocomposite coating and supplementary dissipation of the energy of the normal shock wave that excites generation and propagation of secondary surface waves at the interface of heterogeneous layers of the ceramic coating and quartz.