- 學位論文
反應燒結法製備(A6-xA’x)(B5-xB’x)O18微波介電陶瓷之研究
Reaction-Sintering Process for (A6-xA’x)(B5-xB’x)O18 Microwave Dielectric Ceramics
摘要
本研究以簡單有效的反應燒結法製備Ba3La3Ti4NbO18和Ba2La4Ti5O18微波陶瓷，把原料粉末混合及壓模後未經任何煆燒的步驟而直接燒結，並探討添加物CuO及B2O3對反應燒結法之影響。Ba3La3Ti4NbO18相能夠在1400oC~1500oC燒結4~8小時後生成，1500oC燒結6小時可得最大密度5.37g/cm3，添加1wt% B2O3在1330℃燒結6小時可提高至5.77g/cm3，添加2wt% CuO在1400℃燒結8小時最大密度可達6.23g/cm3。其微波介電特性為： εr = 31.98~45.45、Q×f = 2,221~15,122 GHz、τf = +30.68~+32.81 ppm/℃。Ba2La4Ti5O18相能夠在1400oC~1500oC燒結6~10小時後生成，1500oC燒結10小時可得最大密度5.62g/cm3，添加0.5wt% B2O3在1430℃燒結8小時可提高至5.88g/cm3，添加1wt% B2O3在1370℃燒結8小時降至5.71g/cm3，添加2wt% CuO在1490℃燒結10小時可獲得密度值5.89g/cm3。其微波介電特性為： εr = 34.31~60.72、Q×f = 3,018~22,181 GHz、τf = -43.21~+292 ppm/℃。
關鍵字
微波介電陶瓷並列摘要
Ba3La3Ti4NbO18 and Ba2La4Ti5O18 microwave dielectric ceramics prepared using a reaction-sintering process were investigated. The effect of CuO and B2O3 additions were also studied. In this process, the mixture of raw materials was pressed and sintered directly without any calcination involved. Ba3La3Ti4NbO18 phase could be obtained after 4-8 h sintered at 1400-1500oC. Density reached 5.37g/cm3 for 6 h sintering at 1500oC. It increased to 5.77g/cm3 for 6 h sintering at 1330oC with 1wt% B2O3 addition. With 2wt% CuO addition, 6.23g/cm3 was obtained for 8 h sintering at 1400oC. Properties εr = 31.98~45.45, Q×f = 2,221~15,122 GHz, and τf = +30.68~+32.81 ppm/℃ were found in Ba3La3Ti4NbO18. Ba2La4Ti5O18 phase could be obtained after 6-10 h sintered at 1400-1500oC. Density 5.62g/cm3 was obtained for 10 h sintering at 1500oC. It increased to 5.88g/cm3 for 8 h sintering at 1430oC with 0.5wt% B2O3 addition. Density 5.71g/cm3 was obtained for 8 h sintering at 1370oC with 1wt% B2O3 addition. With 2wt% CuO addition, 5.89g/cm3 was obtained for 10 h sintering at 1490oC. Properties εr = 34.31~60.72, Q×f = 3,018~22,181 GHz, and τf = -43.21~+292 ppm/℃ were found in Ba2La4Ti5O18.