Spark Plasma Sintered ZrO2(Y2O3)-Al2O3-SrSO4 Self-Lubricating Nanocomposites for High Temperature Tribological Applications
Spark plasma sintering is employed to synthesize a variety of self-lubricating ZrO2(Y2O3)- Al2O3 matrix nanocomposites by tailoring the chemical compositions and by adjusting the sintering parameters. Different additives are incorporated into the nanocrystalline ceramics of ZrO2(Y2O3)- 20wt.% Al2O3 to evaluate their potentials as effective high temperature solid lubricants from room temperature to 800oC by using a high temperature friction and wear tester in sliding against alumina ball in air. The density, microstructure, hardness and tribological properties of the sintered nanocomposites have been investigated, as contrasted with the unmodified ceramics, to obtain a better understanding of lubrication mechanisms over a wide temperature range. The ZrO2(Y2O3)-Al2O3-SrSO4 composite exhibits steady-state friction coefficients of less than 0.2 and wear rates in the order of 10-6 mm3/Nm over a broad temperature range from room temperature to 800oC.
Wei Pan and Jianghong Gong
J. H. Ouyang et al., "Spark Plasma Sintered ZrO2(Y2O3)-Al2O3-SrSO4 Self-Lubricating Nanocomposites for High Temperature Tribological Applications", Key Engineering Materials, Vols. 336-338, pp. 1429-1432, 2007