氧化铝-锂霞石复合陶瓷在钢水中抗热震性研究

Research on Thermal Shock Resistance of Alumina-Eucryptite Ceramics in Molten Steels

为了提高氧化铝陶瓷的抗热震性,将具有负膨胀系数的锂霞石加入到Al2O3中,通过无压烧结工艺,制备出了氧化铝-锂霞石复合抗热震陶瓷。结果表明,锂霞石加入量w(锂霞石)=20%,烧结温度为1500℃时,陶瓷样品能够承受钢水中1500℃温差(空冷)的热震破坏。采用SEM对陶瓷进行组织结构分析,发现在基体内部形成片状组织,这样的显微组织对提高陶瓷的抗热震性具有重要作用。

In order to improve the thermal shock resistance of alumina ceramics,eucryptite with negative coefficient of thermal expansion was added into Al2O3 powder, and the alumina-eucryptite ceramics with the good properties of thermal shock resistance was made by means of pressureless sintering technology. The results show that when the mount of additive eucryptite reaching 20% and the sintering temperature is 1500℃,the ceramics can endure the thermal shock with a temperature difference of 1500℃（cooling in air）. The microstructure of ceramics was observed in SEM. It was founded that the flake microstructure has formed in the matrix,and it is one important reason that the thermal shock resistance of the ceramics can be improved effectively.