Microstructure and high temperature deformation characteristics of sol–gel derived aluminium titanate–mullite composites

Abstract

Aluminium titanate (AT)-mullite composites with varying compositions were processed by sol-gel technique. The influence of mullite on the microstructure and creep deformation of AT-mullite composites was investigated. in the composites mullite addition was varied from 0 to 100 vol% The AT-80 vol.% mullite composite sintered at 1600 degrees C resulted in fine-grained microstructure with an average grain size of 2.5 mu m. From the steady-state creep analysis of the different AT-mullite composites, the activation energies for the creep deformation and stress exponents were determined. The activation energies in the range 655-874 kJ mol(-1) were obtained for various the sol-gel derived AT-mullite composites. Similarly stress exponent values were found in the range 1.5-1.9.