Room temperature strength of β-sialon (z=0.5) fabricated using fine grain size alumina powder

Abstract

The room temperature strength of β-sialon with z=0.5 fabricated using a mixture of fine grain size Al2O3 and Si3N4 powders was measured, and the effect of a small, amount of Al(Oi-Pr)3 addition as a dispersant on its strength was also investigated. This β-sialon showed an average strength of 1.00 GPa. It was much higher than that of β-sia1on from traditionally produced Si3N4 and Al2O3 powders as a result of decreasing the size of defects responsible for fracture origin. Mixing of Si3N4 and Al2O3 powders in a Al(Oi–Pr)3 solution brought further increase in strength to 1.25 GPa because of the smaller size and reduced number of defects. However, the strength of β-sialon is still controlled by the defects with the size of less than 10 μm.