The microstructural characteristics and mechanical property of Al fiber-reinforced cordierite ceramics

Al fiber-reinforced cordierite was prepared by solid state reaction of clay, talc and alumina sintered at 1370 °C in carbon embedded condition. The microstructures were observed via scanning electron microscope (SEM), three-point flexural strength was examined on a universal testing machine. The SEM microphotograph shows a weak-bonded interfacial phase AlN, which was attributed to the reaction between Al and N2 at high temperature in carbon protection condition, was formed between cordierite matrix and Al fiber. It facilitates fiber debonding and fiber pullout during fracture test. Three-point flexural test indicates both fracture displacement and flexural strength of Al-reinforced cordierite are bigger than that of the monolithic cordierite. With increasing Al-fiber addition, the higher strength and longer displacement were found.