High-temperature friction and wear properties of X-BaSO4 (X: Al2O3, NiAl) composites prepared by spark plasma sintering

X-BaSO4 (X: Al2O3, Ni-Cr alloy and NiAl) composites were prepared by spark plasma sintering, and their friction and wear properties were investigated from at temperatures ranging from room temperature to 1073 K in air. The friction coefficients of the Al2O3-(50) mass% BaSO4 composites varied from 0.2 to 0.4 at the temperature range. The NiAl-50 mass% BaSO4 composites and Ni-Cr alloy-based composites containing 50 mass% BaSO4 showed low friction coefficients at temperatures over 873 K, although their friction coefficients were higher than 0.5 at 473 K and 673 K. The wear rates of the Al2O3-50 mass% BaSO4 composites Were much higher than those of the NiAl-50 mass% BaSO4 composites and Ni-Cr alloy-based composites containing 50 mass% BaSO, at room temperature. In order to improve the wear resistance of the Al2O3-50mass% BaSO4 composites, it would be necessary to use fine Al2O3 and BaSO4 powders and to add some sintering additives to the composites.