Phase structure and microwave dielectric properties of 0.85(0.74CaTiO3–0.26SmAlO3)–0.15Ca1.15Sm0.85Al0.85Ti0.15O4 composite ceramics prepared by reaction-sintering process.

0.85(0.74CaTiO₃–0.26SmAlO₃)–0.15Ca_1.15Sm_0.85Al_0.85Ti_0.15O₄ (CSC) composite ceramics were prepared by a reaction-sintering method. The phase structure, sintering behavior and microwave dielectric properties of CSC ceramics were investigated. The preparation process of reaction-sintering route (RS) is simple. XRD patterns show that Ca_0.74Ti_0.74Sm_0.26Al_0.26O₃ (similar to CaTiO₃), SmAlO₃ and Ca_1.15Sm_0.85Al_0.85Ti_0.15O₄ phases are formed in the CSC ceramics. The grain size and dielectric constant of CSC ceramics increase with rising the sintering temperature. As the sintering temperature increases, the quality factor (Q × f) and τ_f value of the CSC ceramics increase to the maximum values first and then decrease. The bulk density fluctuates up and down around a value, but little change. The ceramics sintered at 1500 °C got the best microwave dielectric performances with ε_r = 35.9, Q × f = 49,221 GHz, τ_f = − 0.53 ppm/°C. [ABSTRACT FROM AUTHOR]