Wear Behaviour of Laminated Ceramic Composites Containing Residual Stresses

The tribological behaviour of laminated ceramic composites prepared in the system Al2O3-ZrO2 was evaluated by the pin-on-disc method for different loads and sliding speeds. The ocomposites were produced by superimposing alternating layers of Al2O3 and Al2O3/ZrO2 prepared by tape casting. Symmetric structures were obtained, with an alumina surface layer on either side. Due to the different thermal expansion coefficients of the various layers, residual compressive stresses were produced on the surface, leading to an increase in the apparent surface toughness. Through a comparison with the results for stress free alumina, it was verified that the improvement in surface toughness has a positive effect on the wear performance of the composites. Possible wear mechanisms are proposed.