Strength and Thermal Shock Behaviour of Synthetic Mullite

This is the authors' abstract. We don't add key points for this paper.

Synthetic mullite prepared from clay alumina mixture was sintered around 1400°C and at 1600°C to obtain controlled porosity. The sintered compacts were subjected to thermal shock between 1400°C and room temperature, and mechanical strength was evaluated by compressive test measurements at room temperature.The porous (∼20% OP) samples showed densification during thermal shocks. The compressive strength increased up to five thermal cycles and decreased thereafter. The least porous (0.5 to 6% OP) samples retained the strength during thermal shocks while impervious (<0.5% OP) samples showed steady increase in strength. The samples sintered at 1600°C, though impervious, had low strength and cracked after five thermal cycles due to the separation of glassy phase from the matrix resulting in conchoidal fracture.