Continuous fiber reinforced mullite matrix composites by sol–gel processing: Part II Properties and fracture behaviour

Abstract

The mechanical and interfacial properties of the mullite matrix and alumina–silica matrix composites reported in a previous publication [1], are related to the processing parameters. The flexural strengths were in the range of 428–737 MPa, flexural moduli from 82–214 GPa, work of fracture values from 293–482 KJ m-2 and ultimate failure strains from 0.16–0.45%. The interfacial strengths were determined by the fibre push-in test and compared with fracture behaviour. The formation of different interfaces in the composites and the influence of the density of thermally-induced cracks and porosity on flexural modulus is discussed.