Microwave dielectric properties of new SrLa4−xNdxTi5O17 ceramics

New microwave dielectric ceramics in the SrLa4−xNdxTi5O17 (0 ≤ x ≤ 4) composition series were prepared through a solid state mixed oxide route. All the compositions formed highly dense (∼95%) single phase ceramics upon sintering at 1500–1580 °C. The molar volume and theoretical density decreased due to the substitution of small (1.27 Å) Nd ions for large (1.36 Å) La ions. This decrease was associated with a decrease in the dielectric constant (ɛr), temperature coefficient of resonant frequency (τf) and quality factor (Qufo). An analysis of properties achieved in the present study indicated that ceramics exhibiting nearly zero τf corresponding to ɛr ∼ 54 could be fabricated in the SrLa4−xNdxTi5O17 composition series at x ∼ 1.6; however, further work is required to improve Qufo (∼6000 GHz) for possible practical applications.

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► New microwave dielectric SrLa4−xNdxTi5O17 (0 ≤ x ≤ 4) ceramics were processed.
► All the compositions sintered to 95% dense single phase ceramics at 1500–1580 °C.
► τf ∼ 0 corresponded to ɛr ∼ 54 for SrLa4−xNdxTi5O17 (x ∼ 1.6) with Qufo ∼ 6000 GHz.
► Further work is required to improve Qufo for practical applications.