SURFACE UPLIFT AND WEAR IMPLICATIONS OF ZIRCONIA-TOUGHENED CERAMICS

Zirconia ceramics have shown promising wear properties in a number of applications. However, in certain load configurations the wear perform ance is very poor. The reason for this is believed to be subsurface ph ase transformation. The surface uplift due to transformation of a circ ular inclusion in a half-plane and of a spherical inclusion in a half- space is analyzed. The general uniform transformation strain has signi ficant effects on the surface topography and has ramifications for the rolling/sliding wear characteristics of the surface. The two-dimensio nal approximation overestimates the surface uplift by up to three time s compared with the more realistic three-dimensional model. The result s indicate that the occurrence of transformation strains, and in parti cular shear transformation strain, in the near surface area will affec t the surface topography considerably.