TiO_2晶型对0.65CaTiO_3-0.35LaAlO_3陶瓷介电性能的影响

Influence of TiO_2 Crystalline Phases on the Microwave Dielectric Properties of 0. 65CaTiO_3-0. 35LaAlO_3 Ceramic

采用两种晶型不同的TiO2微粉为原料,通过传统的固相反应工艺分别制备了0.65CaTiO3-0.35LaAlO3陶瓷,系统地研究了这两种TiO2原料对陶瓷的晶体结构、微观结构和微波介电性能的影响。实验结果表明,TiO2原料晶型的不同显著影响了0.65CaTiO3-0.35LaAlO3陶瓷的微波介电性能。对于金红石型TiO2原料,所制备陶瓷的最佳烧结温度为1440℃,其微波介电性能为εr=43.8、Q×f=38216GHz、τf=-10.5ppm/℃。而采用锐钛矿型TiO2原料制备的陶瓷的最佳烧结温度为1580℃,陶瓷的微波介电性能为εr=37.5、Q×f=45200GHz、τf=5.3ppm/℃。该研究结果有助于选择合适的TiO2原料以制备出性能良好的CaTiO3-LaAlO3陶瓷,也为进一步研制和开发新组分的CaTiO3-LaAlO3系微波介质陶瓷材料奠定了基础。

Two different crystalline phases of Ti O2 raw materials were deliberately chosen to prepare 0.65 Ca Ti O3-0. 35 La Al O3 ceramics through the conventional solid-state reaction method. Systematic investigation on the microstructures, crystalline structures, and microwave dielectric properties was carried out. It was observed that 0. 65 Ca Ti O3-0. 35 La Al O3 ceramics prepared with different crystal types of Ti O2 raw materials show quite different microwave dielectric properties. The optimum property of εr=43. 8,Q · f = 38216 GHz and τf=-10. 5 ppm / ℃ was obtained for the ceramic prepared with rutile titanium dioxide sintered at 1440 ℃ concerning the ceramic prepared with anatase titanium dioxide,it possessed the properties of εr= 37. 5,Q·f = 43200 GHz and τf= 5. 3 ppm / ℃ sintered at 1580 ℃. The study results should be useful for practical applications and instructive for further compositional designs of Ca Ti O3-La Al O3-based ceramics.