Influence of hydrothermal degradation on wear behaviour of zirconia tetragonal polycristals doped with 3% molar of yttria

Abstract

The goal of this work is to analyse the influence of hydrothermal degradation on wear behaviour on samples of tetragonal polycrystals doped with 3% molar of yttria in air under dry sliding conditions on samples artificially aged at 0, 10 and 60 hours in autoclave at 131°C. The samples were prepared by conventional compaction and sintering at 1450°C. The study was carried out by performing scratch tests and ball on disc experiments against 3Y-TZP balls. At low loads the damage was not distinctive, but under high loads the damage mechanisms were different suggesting a clear effect of degradation after long ageing times. On the contrary, in samples degraded during 60 hours the wear rates in both experiments were initially higher than on non-aged specimens and decreased with increasing load and/or sliding distance.