High-temperature tribological properties of Al2O3-X (X: BaCrO4, BaSO4 and CaSO4) spark-plasma-sintered composites containing sintering additives

Abstract

Composites of Al2O3-X (X: BaCrO4, BaSO4 and CaSO4) systems were prepared by spark plasma sintering, and their friction and wear properties were evaluated from room temperature to 1073 K. With the addition of Na2SiO3, SiO2 and Ag to the Al2O5-BaCrO4 composites exhibited improved densification. In particular, the wear rates of the Al2O3-BaCrO4 composites were notably reduced from room temperature to 1073 K with the addition of SiO2. Al2O3-BaSO4 composites, both with and without SiO2 as a sintering additive, showed friction coefficients as low as 0.5 from room temperature to 1073 K, while the friction coefficients of the Al2O3-50CaSO4-5SiO2 (mass%) composites were as high as 1.2 at 473 K.