Microstructural investigations in cordierite-mullite refractories

摘要: Abstract The influence of the mineralogical composition and phase distribution on crack initiation propagation in cordierite–mullite refractory plates used as substrates fast firing porcelain whiteware is investigated. Two different compositions (termed REFO CONC), characterised by silica to alumina ratios, were studied. Propagation cracks introduced Vickers’ indentations was observed scanning electron microscopy. Chemical analysis EDS for identification together with X-ray diffraction analysis. Microstructural features behaviour correlated draw conclusions two under thermal shock. It found that presence α-quartz crystals favourable residual stress field are responsible room temperature fracture toughness samples. CONC material contains a larger amount glassy than material, which should lead better high-temperature mechanical properties higher shock resistance, glass may close (“heal”) propagating cracks.