Role of Nano‐ and Micron‐Sized Particles of TiO ₂ Additive on Microwave Dielectric Properties of Li ₂ ZnTi ₃ O ₈ – 4 wt% TiO ₂ Ceramics

Abstract

Microwave dielectric ceramics with the composition of Li 2 ZnTi 3 O 8 – 4 wt% TiO 2 were synthesized by the conventional solid‐state reaction. 4 wt% TiO 2 powders with different particles size were added to the Li 2 ZnTi 3 O 8 ceramic. Then the ceramic samples were sintered at temperatures 1075°C, 1050°C, 1000°C, and 950°C for 4 h. The effect of the particles size of TiO 2 additive on the microwave dielectric properties of the ceramics has been investigated. In the study two categories of particles size of TiO 2 additive have been used; (i) Nanoparticle (50 nm), (ii) Micron sized (40, 5, 1 μm) powder. X‐ray showed that the TiO 2 additive has not solved in the LZT structure and has not almost undergone chemical reaction with the LZT ceramic. The results showed that the addition of TiO 2 nanoparticles to the LZT ceramics significantly improved the density and a dense and uniform microstructure and also abnormal grain growth were observed by SEM . The use of TiO 2 nanoparticle reduces porosity and leads to an increase in green density. The maximum density was found to be 98.5% of the theoretical density and the best relative permittivity of 28, quality factor of 68000 GHz and τ f value of −2 ppm/°C were obtained for the samples added with 4 wt% of the TiO 2 nanoparticles, sintered at 1050°C for 4 h.