Effect of Y2O3-addition on the crystallographic and mechanical properties of the Ce-TZP/Al2O3 composite

Abstract

Abstract The effect of adding different Y2O3 contents on the physical and mechanical properties of Ce-TZP/Al2O3 composites was investigated. Ce-TZP/Al2O3 powder blends containing 1~10 wt% Y2O3 were compacted at 100 MPa-30 s and sintered at 1500 °C-2 h or 1600 °C-2 h. The materials were characterized by X-ray diffraction and scanning electron microscopy, Raman spectroscopy, relative density, and the mechanical properties of Vickers hardness and fracture toughness. After sintering, the relative density of the sintered samples varied between 92.7% and 96.3%. Furthermore, the addition of Y2O3 resulted in an increase in the amount of cubic zirconia (c-ZrO2) and an increase in grain size in relation to the sample without the addition of Y2O3. With the increase of Y2O3 in the composition and consequent increase in the cubic ZrO2 phase content, although the hardness values did not present statistically significant variations, indicating average value of 12 GPa, a decrease in fracture toughness values was observed (10.0~5.5 MPa.m1/2) as a direct function of the reduction in the population of tetragonal zirconia grains, responsible for the toughening mechanism by phase transformation in these composites.

Keywords

• Ce-TZP/Al2O3
• Y2O3 composite
• Rietveld refinement
• Raman spectroscopy
• mechanical properties