Effect of heat treatment on wear damage mechanisms in 3Y-TZP ceramics

Two 3Y-TZP materials (polycrystalline Zirconia stabilized by 3% of yttria) with different heat treatment (i.e. different grain size) have been prepared in order to study the effect of different microstructure (i.e. different grain size) on their tribological behaviour. The ball-on-disc technique in dry conditions at different sliding speeds was used. Worn and unworn surfaces were observed using SEM and optical microscopy. The wear regimes as functions of speed have been identified. The wear damage increased significantly with increasing sliding speed. The mild-to-severe wear transition occurred at the wear rate of similar to 10(-5) mm(3)/mN which is in accordance with the literature data. The wear damage micromechanisms corresponding to various degrees of wear have been studied and are discussed in detail. It has been found that at the low wear regime both materials behave identically, under more severe conditions, however, the material with finer grains exhibited better wear resistance. (C) 2010 Elsevier B.V. All rights reserved.