Fabrication, Microstructure and Properties of Nitrides Bonded Alumina Castables by in-situ Nitridation Reaction

摘要

Nitrides(Si_3N_4/Sialon) bonded alumina castables were fabricated by in situ nitridation reaction. Effects of the formation of nitrides on the physical properties, hot strength and thermal shock resistance were investigated. The results show that the phase composition of castables is alumina, α-Si_3N_4, β-Si_3N_4 and Si_2N_2O after fired at 1400°C and 1450°C, and is alumina, β-Sialon and O'-Sialon after fired at 1500°C. Hot modulus of rupture and thermal shock resistance of specimens are noticeably improved due to the formation of nitrides.