Influences of SrSO4 and Ag on High Temperature Tribological Properties of Spark-Plasma-Sintered ZrO2(Y2O3)-Al2O3 Composites
ZrO2(Y2O3)-Al2O3-SrSO4 nanocomposites incorporated with and without Ag addition have been fabricated by spark plasma sintering (SPS) to evaluate their friction and wear properties in sliding against alumina ball from room temperature to 600 oC. X-ray diffraction (XRD), scanning electron microscope (SEM) and Raman spectroscopy were used to investigate microstructure and self-lubrication mechanisms of nanocomposites after wear tests at different temperatures. The ZrO2(Y2O3)-Al2O3-SrSO4 nanocomposite exhibits low and stable friction coefficients of 0.2 to 0.3 and wear rates in the order of 10-6 mm3/Nm at high temperatures. With the addition of Ag into the composite, the intermediate temperature lubricating property is greatly improved. Plastic deformation of SrSO4 and sliver during sliding plays an important role in formation of lubricating films on worn surfaces of nanocomposites. These lubricating films reduce the friction and wear of the ZrO2(Y2O3)-Al2O3 matrix composites.
Wei Pan and Jianghong Gong
Y. F. Li et al., "Influences of SrSO4 and Ag on High Temperature Tribological Properties of Spark-Plasma-Sintered ZrO2(Y2O3)-Al2O3 Composites", Key Engineering Materials, Vols. 434-435, pp. 138-143, 2010