Herzian Contact Fatigue Test of Y-PSZ and Y-PSZ/Al2O3 Ceramics in Hot Water.

Abstract

A Hertzian contact fatigue test was proposed to simulate conventional rolling wear experiments, by which the wear behavior and phase transformation of 3mol%Y2O3-partially stabilized zirconia (3Y-PSZ) and 3Y-PSZ/20 mass%Al2O3 ceramics in water at 90°C were investigated. The Hertzian stress contact fatigue property was found to be greatly dependent on fracture strength and remarkably improved by the post-HIP treatment. The Hertzian contact stress was revealed to have minor influence on the water-assisted tetragonal-to-monoclinic phase transformation in Y-PSZ-based ceramics at temperatures as low as 90°C. The addition of Al2O3 into Y-PSZ effectively suppressed the low-temperature phase transformation, but it did not lead to the improvement in the contact fatigue property probably because the strength of the resultant composite was lower than the monolithic Y-PSZ; however, more work is required to completely understand the Hertzian stress contact fatigue behavior of composites.