Cubic Phase Stabilization of Translucent Yttria‐Zirconia at Very Low Temperatures

Abstract

Simultaneous decomposition of yttrium and zirconium alkozides was used to obtain an almost ideal mixture of powders of high surface activity. From this powder a translucent body, “Zyttrite,” was made with a grain size of less than 1μ. The mixed oxide was consolidated into a stabilized body by firing at 1000°C for 30 min. This is indicative of a phenomenal increase in solid state reactivity. High‐density fully stabilized cubic solid solutions of 6 mole % Y 2 O 3 ‐ZrO 2 were obtained on sintering at 1450°C. A typical specimen had a density of 5.9 g/cm 3 , a coefficient of thermal expansion of 11 × 10 −6 in./in.°C, and a grain size of 2 to 4μ. Test pieces withstood 2200°C firings in air for 262 hr with grain growth of 35 to 50μ and virtually no change in composition, density, or stabilization.