Preparation and Wet Erosive Wear Characteristics of Porous Al2O3 Ceramics
Porous Al2O3 ceramics were produced by a dry pressing technique and their characteristics were assessed. In terms of their microstructure the results showed that the open porosity varies with the type of pore-making agents. The open porosity is increased but fracture strength is decreased with an increase in the amount of pore-making agent. The fracture strength of Al2O3 ceramic matrix is increased by adding 5-15wt% ZrO2 particles (ZTA). In terms of their wet erosive wear characteristics the results from liquid-solid impinging jet tests can be used to determine the weak aspects of their microstructure. From examination of worn surfaces it is apparent that grain pull-out is the dominant mechanism of erosive wear. For the porous ceramics, wet erosive wear rate depends on strength, porosity and pore size. For porous Al2O3 ceramics having the same level of porosity, the larger the biggest pore size the higher the erosive wear rate. ZTA composite ceramic has a higher erosive wear resistance than that of Al2O3 ceramic with an equivalent level of porosity primarily due to its higher strength.
Wei Pan and Jianghong Gong
X. P. Liang et al., "Preparation and Wet Erosive Wear Characteristics of Porous Al2O3 Ceramics", Key Engineering Materials, Vols. 336-338, pp. 2458-2461, 2007