水基凝胶注模成型工艺制备0.9Al2O3-0.1TiO2陶瓷的微波介电性能

摘要

The aqueous gelcasting was used to prepare 0.9Al2O3-0.1TiO2 ceramics.The microstructures,phase compositions and microwave dielectric properties of sintered 0.9Al2O3-0.1TiO2 ceramics were investigated.With the help of proper calcination temperature (1200℃) and continuous and slow cooling process as annealing treatment,the Al2TiO5 secondary phase was successfully eliminated.Compared with conventional dry pressing method,bigger grains,less pores and more uniform microstructures are observed in the 0.9Al2O3-0.1TiO2 ceramics prepared by aqueous gelcasting.Therefore,much better microwave dielectric properties are obtained in the ceramics prepared by aqueous gelcasting with εr= 10.71,Q × f= 20421GHz,τf= 1.3×10-6/℃,whereas that of ceramics prepared by dry pressing are εr = 10.89,Q × f= 11938GHz,τf= 1.4 × 10-6/℃.%采用水基凝胶注模成型工艺制备了0.9Al2O3-0.1TiO2陶瓷.研究了烧结后的0.9Al2O3-0.1TiO2陶瓷的微结构、相组成以及微波介电性能.通过采用合适的预烧温度(1200℃)和连续、缓慢的降温工艺来退火,成功消除了Al2TiO5第二相.和传统干压法相比,用水基凝胶注模成型工艺制备的0.9Al2O3-0.1 TiO2陶瓷具有较大的晶粒,较少的气孔和更加均匀的微结构.因此,用水基凝胶注模成型工艺制备的0.9Al2O3-0.1TiO2陶瓷拥有更好的微波介电性能:εr=10.71,Q×f=20421GHz,τf=1.3×10-6/℃,而用传统干压法制备的0.9Al2O3-0.1TiO2陶瓷的微波介电性能为εr=10.89,Q×f=11938GHz,τf=1.4×10-6/℃.