Studies On Friction And Wear Of (Ce, Mg)-PSZ Ceramics

Magnesia, Ceria partially stabilized zirconia (Ce, Mg)-PSZ ceramics with net shape microstructure are prepared using a processing method similar to that of conventional Mg-PSZ ceramics, Investigations are focused on the effects of CeO2 concentration and heat treatments on the microstructure and phase composition of (Ce, Mg)-PSZ ceramics when molar ratio of MgO/ZrO2 is 10/90 . The friction and wear of (Ce, Mg)-PSZ ceramics were systematically investigated using a block-on-block tribometer in different lubricants (mainly in dry friction) at varying loads.The addition of CeO2 could impede the formation of monoclinic phase and inhibit the growth of cubic grains. The microstructure of (Ce, Mg)-PSZ changed slightly when CeO2 concentration varying in the range of 4～8mol%; microstructure with net-shaped structure cubic grains, in which tetragonal precipitates interweave to a nanoporous structure is obtained. The t-ZrO2 precipitate morphology might be related with the addition of CeO2 and the heat treatment temperatures.(Ce, Mg)-PSZ ceramics showed good wear resistance when sliding at low loads in dry friction, the main wear mechanisms are plastic deformation and micro-fracture, while fracture is the dominant when loads increased. Surface adhesion and friction heat corrosion might be the important causes that made the wear resistance of (Ce, Mg)-PSZ ceramics decline. Net shape structure could effectively absorb and relieve the strain energy produced by friction, which is in favor of better wear resistant properties of (Ce, Mg)-PSZ ceramics. A preliminary study of the formation of tribo-film and its work mechanisms has been performed.