采用溶胶-凝胶法制备Ca0.25(Li0.43Sm0.57)0.75TiO3(CLST)微波介质陶瓷纳米粉体,研究了ZnO掺杂量和烧结温度对CLST+xmol%ZnO陶瓷烧结性能和微波介电性能的影响。XRD分析结果表明：随着ZnO掺杂量x的增加,陶瓷的晶体结构从正交相变为伪立方相,并在x≥1.5的样品中出现了杂相。CLST+xmol%ZnO陶瓷的致密化烧结温度随x的增加而降低, x=1.0的样品的致密化烧结温度比x=0的降低了200℃。介电常数εr和频率品质因数Qf 随x增加和烧结温度的升高具有最优值,频率温度系数则单调降低。x=1.0的样品在1100℃烧结时具有优异的综合性能：ρ=4.85 g/cm3,εr=102.8, Qf=5424 GHz,τf=-8.2×10-6/℃。表明ZnO掺杂的CLST陶瓷是一种很有发展潜力的微波介质陶瓷。%The Ca0.25(Li0.43Sm0.57)0.75TiO3 (CLST) ceramic nano-powder was prepared by Sol-Gel method. The in-fluences of ZnO doping content and sintering temperature on sintering behavior and microwave dielectric properties of CLST ceramics were investigated. A phase transition from orthorhombic to pseudo cubic symmetry was identi-fied by XRD analysis, and a impure phase was found in the x≥1.5 samples. The densification sintering temperature of the CLST+xmol% ZnO ceramics decrease with increasing ZnO doping content, and it reduces from 1300℃ to 1100℃ when the amount of ZnO doping increase from x=0 to x=1.0. The results also reveal that both the dielectric constantεr and the quality factor Qf possess a peak value with increasing ZnO doping content or sintering tempera-ture, whereas the frequency temperature coefficientτf decrease monotonously. The x=1.0 sample sintered at 1100℃for 2 h has optimal microwave dielectric properties:ρ=4.85 g/cm3,εr=102.8, Qf=5424 GHz,τf=-8.2×10-6/℃, respectively, which indicates that the CLST ceramic doped with 1.0mol%ZnO is a promising microwave dielectric ceramic.
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