Effect of the Zirconia Particle Size on the Compressive Strength of Reticulated Porous Zirconia-Toughened Alumina

Abstract

Reticulated porous ceramics have attracted researchers owing to the separation and collec-tion properties of porous materials and the combined high thermal resistance and chemical stability of ceramics. Among various kinds of reticulated porous ceramics, we investigated the feasibility of using reticulated porous Zirconia-toughened Alumina as applications such as dielectric barriers, insulators, and filters with acceptable properties. An acceptable range of the compressive strength for reticulated porous ZTA applications is approximately 1 MPa. However, when the pore density of the reticulated porous ZTA specimen prepared using coarse zirconia was 60, maximum compressive strength of 1.63 MPa was obtained. To enhance the compressive strength of reticulated porous ZTA specimens, rheological control of the ZTA slurry is most important by optimizing the viscosity of the ZTA slurry, and the composition (average particle size, solid loading, organic binder, and thickener) of the ZTA slurry was controlled. The optimized processing conditions to enhance the compressive strength of reticulated porous ZTA specimens were determined. Consequently, we enhanced the compressive strength of the reticulated porous ZTA specimens from 0.37 MPa to 3.11 MPa by optimizing the ZTA slurry when the solid loading content, the pore density, the sintering temperature, the amount of PVA, and the amount of thickener were 66 wt.%, 60 PPI, 1600◦ C, 2 wt.%, and 0.15 wt.%, respectively.