Dynamic formation of zircon during high temperature deformation of zirconia–silica composites with alumina additions

摘要: A three phase ceramic composite of 8 mol% Y2O3 stabilized ZrO2 (YSZ), SiO2, and Al2O3 was evaluated for potential high temperature superplasticity. The amorphous SiO2 content 5 wt.%, increasing additions were made. effect varying the stabilizer concentration in also studied. Samples sintered at 1200 °C contained only YSZ, Al2O3, but ZrSiO4 formed samples above 1300 °C. Mullite (3Al2O3 · 2SiO2) not detected any samples. Specimens 1 wt.% Al2O3–YSZ/SiO2 had an anomalously deformation rate ∼2 × 10−4 s−1 when compared to YSZ/SiO2 without (∼4 10-5 s−1). Higher amounts decreased strain rate. Extensive doped induced formation due enhanced reaction rates. This distributed, yet locally interconnected, zircon rapidly eroded after ∼60% deformation.