- 學位論文
反應燒結法製備Ba5Nb4O15與Sr5Nb4O15微波介電陶瓷及摻雜Mg之研究
Reaction-Sintering Process for Ba5Nb4O15 and Sr5Nb4O15 Microwave Dielectric Ceramics and the Effect of Mg Addition
摘要
在本研究中使用反應燒結法製備Ba5Nb4O15與Sr5Nb4O15微波介電陶瓷，並摻雜不同量的Mg及添加CuO來分析其微結構及微波介電特性。製程中，把原料粉末混合及成型後未經過任何煆燒的步驟而直接燒結。藉由反應燒結法可以獲得純的Ba5Nb4O15與Sr5Nb4O15相。摻雜Mg時，可降低燒結溫度50~100℃，添加CuO時，則可再降低100~200℃。Ba5Nb4O15燒結在1450℃持溫4小時可達到理論密度值97.3%，Sr5Nb4O15添加CuO燒結在1430℃持溫4小時可達到理論密度值96.0%，摻雜Mg及添加CuO也可達到不錯的密度值。Ba5Nb4O15陶瓷系列其微波介電特性為： εr = 36.69~45.18、Q×f = 16,086~43,878 GHz、τf = 37.6~63.2 ppm/℃。Sr5Nb4O15陶瓷系列其微波介電特性為： εr = 38.08~41.69、Q×f = 8,476~13,426 GHz、τf = 25.6~50.9 ppm/℃。
並列摘要
Ba5Nb4O15 (BN) and Sr5Nb4O15 (SN) microwave dielectric ceramics prepared by a reaction-sintering process were investigated. The effect of Mg doping and CuO addition was also studied. In this process, the mixture of raw materials was pressed and sintered directly without any calcination involved. Single phase BN and SN could be obtained. The sintering temperature was 50~100℃ lowered by Mg doping and 100~200℃ further lowered with CuO addition. With CuO addition, 97.3% and 96% of theoretic density were found in BN for 1450℃/4h sintering and SN fore 1430℃/4h sintering, respectively. Properties εr = 36.69~45.18, Q×f = 16,086~43,878 GHz, τf = 37.6~63.2 ppm/℃ for BN based and εr = 38.08~41.69, Q×f = 8,476~13,426 GHz, τf = 25.6~50.9 ppm/℃ for SN based ceramics were obtained.