Surface Modifications of Ceramic Gas-Dynamic Seal by Pulse-Periodic Laser Processing

The feasibility of surface modifications of a gas dynamic seal made of silicon carbide ceramic by microstructuring to reduce the friction coefficient for use in stationary gas-turbine equipment has been determined. Laser irradiation was applied to samples of ceramic material based on silicon carbide, and the surfaces of gas-dynamic seals of the compressor rotor in a gas turbine engine were processed in a pulse-periodic mode. Laser processing resulted in the smoothing of microrelief on the polished surface of silicon carbide ceramic, as confirmed by the analysis of the processed surface profile. A reduction in the average friction coefficient was observed as a result of pulse-periodic laser exposure. The application of optical systems incorporating elements of diffractive computer optics is recognized as a forward-looking trend. The utilization of such systems significantly improves the precision and quality of laser processing.