Microstructure and Mechanical Properties of Textured Alumina-Zirconia Composites Prepared by Compressive Deformation

Abstract

3Y-ZrO_2/Al_2O_3 fine-grained composite compacts were prepared by vacuum hot pressed sintering and then compressed at elevated temperatures.The microstructure and mechanical properties of the composites before and after deformation were investigated.Results show that the apparent textured microstructure is observed in the deformed ceramics through XRD and X-ray pole figure measurement.The maximum degree of texture reaches 7.3 times random.As the true strain increases, bending strength,fracture toughness and Vickers hardness increase up to 933.8MPa,10.4MPa.m~(1/2) and 20.4GPa,respectively.When the true strain increases to 1.72,the mechanical properties decrease to some extent.It is concluded that the texture effectively improves the mechanical properties of the composite ceramic,while the coarsening grains and big cavities formed under extremely high strain induce the decrease of mechanical properties.