Brush-on-disc simulation tribotesting of materials for gas turbine-compliant seal components

A brush-on-disc tribometer was used for high-speed, high-temperature sliding experiments on materials simulating conditions in turbine flexible element gas path seals. Of the polymeric, ceramic and metallic material pairs tested only superalloy wires sliding against ceramic surfaces were promising candidates. After extensive running-in, nickel-based wires wore at a rate close to 10⁻⁸ mm³/N m when sliding under moderate loads at speeds to 100 m/s and temperatures to 500°C against a Cr₃C₂/NiCr coated counterface whose wear was also very low. Thus, useful seal life under engine operating conditions may result, depending upon allowable initial and minimum effective brush-rotor interferences.