Fabrication and properties of fibrous porous mullite–zirconia fiber networks with a quasi-layered structure

A novel anisotropy porous mullite fiber network with a quasi-layered microstructure was prepared by vacuum squeeze moulding and sintering. The effects of the initial pressure used in vacuum moulding on the microstructure, thermal properties and mechanical properties of the fibrous porous mullite ceramic were studied. Zirconia fiber was introduced into the ceramic, and the effects of altering the fiber content on the pore structure, porosity and properties of the final ceramic were investigated. Results show that the ceramics prepared in this study exhibited high compressive strength (∼5.16 MPa in the x/y direction) and low thermal conductivity (∼0.094 W/(m K)). This study also reports an optimal processing method for the production of fibrous porous mullite–zirconia composites, which have the potential for use as ultra-high-temperature thermal insulation material.