红柱石基刚玉-莫来石复相陶瓷的显微结构及性能

MICROSTRUCTURE AND PROPERTY OF ANDALUSITE BASED CORUNDUM-MULLITE DUPLEX CERAMICS

以红柱石颗粒为主要骨料,辅以莫来石颗粒和刚玉颗粒,硅微粉、铝微粉为基质料,经混合、困料及成型后,经不同温度下烧成4h,制得莫来石基刚玉-莫来石复相陶瓷,分析了烧成温度对复相陶瓷的物相组成、显微结构、烧成性能、力学性能及热学性能。结果表明:红柱石在高温下转化成针状和柱状莫来石改善复相陶瓷的烧成性能和抗热震性能;在1480℃烧成时,红柱石刚玉-莫来石复相陶瓷具有优越性能,其抗折强度为15.4MPa,耐压强度为91.6MPa,热膨胀系数为5.5×10-6/K,1100℃下水冷的抗热震次数达到99次。

Using andalusite particles as the main aggregate,corundum and mullite particles as the auxiliary,Al2O3 and SiO2 powder as the matrix,corundum-mullite duplex ceramic was prepared after aging the mixture,molding it into forms and sintering it at different temperatures for 4 hours.Effects of sintering temperatures on phase composition,microstructure,sintering properties,mechanical and thermal properties of duplex ceramic were studied.The results showed that andalusite transformed into needle and cylindrical mullite at high temperature,which improved duplex ceramic＇s sintering property and thermal shock resistance.Corundum-mullite duplex ceramic had excellent comprehensive properties when the sintering temperature was 1480℃ ： the flexural strength was 15.4MPa,the compressive strength was 91.6MPa,the thermal expansion coefficient was 5.5 ×10-6/K,and the resistance number of thermal shock tests by water quenching after heating to 1100℃ reached 99.