采用固相反应法制备了xSrTiO3-（1-x）LaAlO3（x=0．4～0．7）介电陶瓷，分析了不同x值陶瓷的结构和介电性能。结果表明：该陶瓷主相为钙钛矿固溶体，x=0．4～0．5时，为正交钙钛矿结构，在x=0．55-0．7时，为赝立方钙钛矿结构；赝立方结构的陶瓷具有较高的介电常数（ε〉50）和低介电损耗（10^-3～10^-4）及近零的温度系数；陶瓷从赝立方结构转变成正交结构时，介电常数明显下降（ε=34-45），介电损耗迅速增大（约101）；x=0．6，0．7的陶瓷具有优良的介电性能，ε〉55，tanδ在10^-3～10^-4之间（f=1MHz）；x=0．4时陶瓷具有优异的微波介电性能，ε=30．5，Qf=40177GHz，rf=-22．9×10^-6℃-1。。%xSrTiO3-（1-x）LaAlO3（x=0.4-0.7 dielectric ceramics were prepared by solid state reaction method, the structure and properties of ceramics with different x value were discussed. The results show that perovskite solid solution was the main phase of this ceramics. The perovskite were orthogonal structure and constrain cubic structure when x were 0. 4--0. 5 and 0. 55--0. 7 respectively. The ceramics with the pseudocubic structure exhibited the higher dielectric constant （ε〉 50）, lower dielectric loss （10 3_ 10-4）and near-zero temperature coefficient. The dielectric constant decreased obviously （ε= 35--45） and dielectric loss increased rapidly （about 10.2） when the ceramics transformed from orthogonai structure to the constrain cubic structure. Good dielectric properties （ε）55, tan 3 of the ceramics was about 10 -3- 10-4 at 1 MHz）were achieved when x was 0.6 and 0. 7. Excellent microwave dielectric properties of ceramic （x=0. 4） were achieved as following： ε=30.5,Qf=40177GHz,rf=-22.9×10^-6℃-1.
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