High-temperature tribological properties of strontium sulfate films formed on zirconia-alumina, alumina and silicon nitride substrates

In our present study, Al2O3, (ZrO2–3 mol% Y2O3)–39.6 mass% Al2O3 and Si3N4 substrates coated with SrSO4 and SrSO4–10 mass% Ag films were prepared, and the friction and wear properties of these specimens were investigated using a reciprocating ball-on-disk tribometer in the temperature range from room temperature to 1073 K in air. It was clarified that (ZrO2–3 mol% Y2O3)–39.6 mass% Al2O3 substrates coated with chemically precipitated SrSO4 particles and the substrates coated with SrSO4–10 mass% Ag films prepared by mechanically grinding and annealing at 1073 K for 3.6 ks exhibited low friction coefficients and low wear rates at all the testing temperatures. In addition, the average friction coefficients of Si3N4 substrates were reduced above 673 K by coating with chemically precipitated SrSO4 particles.