Sintering behaviour and microwave dielectric properties of a new complex perovskite: (1 − x)(Sr0.3Ca0.427Nd0.182)TiO3−x SmAlO3 ceramics

Structural features and microwave dielectric properties of (1−x)(Sr0.3Ca0.427Nd0.182)TiO3−x SmAlO3 (0.05≤x≤ 0.4) ceramics were investigated. X-ray diffraction patterns illustrated that solid solutions with the orthorhombic perovskite were shown to be formed in the ranges of 0.05≤x≤ 0.4. Moreover, the dielectric constant (e r ) of sintered ceramics had a quasi-linear decrease with the increase in SmAlO 3 content. A certain amount of Sm and Al substitution for A- and B-sites could substantially improve the quality factor (Qf) of the ceramics. Increasing the oxygen octahedral distortion led to a decrease in the temperature coefficient of the resonant frequency (τ f) from 216.3 to −34.8 ppm°C−1. Additionally, optimized microwave dielectric properties can be achieved for the specimens using 0.75(Sr0.3Ca0.427Nd0.182)TiO3–0.25SmAlO3 ceramics [e r ∼ 58.3, Qf ∼18800 GHz (at 4.65 GHz) and τ f∼ 2.3 ppm°C−1] after being sintered at 1500°C for 4 h.