2015 年 64 巻 8 号 p. 609-612
Aluminium titanate (Al2TiO5:AT) is known as one of the low expansion ceramics for high temperature uses. However, its low fracture strength makes the ceramics less useful in industry applications. Recently, the present authors reported that the feldspar-doped AT ceramics exhibit better mechanical strength and maintain a low expansion coefficient. It is expected that silica, as one of the main constituents of the feldspar, plays a crucial role for the improved thermal and mechanical properties. In the present study, effects of silica doping on the thermal and mechanical properties of AT ceramics are examined. The silica-doped AT ceramics exhibit improved mechanical property in addition to the low thermal expansion coefficient. It was found that the Si doping into AT lattice and the residual glassy phase at the grain boundaries improved the properties.