Study of near surface changes in yttria-doped tetragonal zirconia after low temperature degradation

Abstract

Study of near surface changes in yttria-doped tetragonal zirconia after low temperature degradation Full tetragonal 3 mol.% Y 2 O 3 doped zirconia has been subjected to hydrothermal ageing in water at 131 8C in order to study the change in microstructure just below the surface. The degraded layer was examined by scanning and transmission electron microscopy in a section perpendicular to the surface which was prepared by focus ion beam machining. The existence of microcracks and transformed grains in a thin surface layer of the hydrothermal degraded specimens is shown. Scratch damage in annealed and in thermally degraded specimens is compared.

Effect of Low Temperature Degradation on Scratch Behaviour of 3Y-TZP

“…Microstructure of the experimental materials has been studied in detail elsewhere [2]. The character and thickness of the degraded layer depend strongly on the initial material.…”

Corrosion of Ceramic Materials

“…The same mechanism that causes toughening results in accelerated aging/corrosion of ZrO 2 ceramics: water or even water vapor can destabilize t-ZrO 2 . If the monoclinic phase content is high, the arising stresses result in the formation of microcracks and grain lifting (spalling) (Bartolome et al, 2004;Chevalier et al, 2009;Lawson, 1995;Li & Watanabe, 1998;Lughi & Sergo, 2010;Marro et al, 2009;Tan et al, 1996). This process starts on the surface, increasing the surface roughness and influencing the wear behavior.…”