Tape Cast AI2O3/ZrO2 Composite Laminates

Fine Al2O3 and ZrO2 powders have been used to fabricate flexible ceramic sheets via the tape‐casting process. The sheets are then formed into simple laminate shapes by stacking and thermocompression, after which the laminates are subjected to a controlled binder removal cycle. Hot‐pressing (sinter‐forging) of laminates results in the retention of very fine grain sizes, close to that of the original powder, with densities in excess of 98% of theoretical. Pressureless‐sintering did not result in complete densification due to the formation of higher density regions at tape interfaces leading to constrained sintering in two dimensions. Pressureless‐sintered composite laminates were superplastically deformed to ∼ 100% strain using a biaxial flexure test at temperatures of the order of 1450°C, without significant grain growth.