Phase evolution and microwave dielectric characteristics of Ti-substituted Mg2SiO4 forsterite ceramics

Abstract In the present paper, the phase evolution and microstructures of Ti-substituted Mg 2 SiO 4 forsterite ceramics with nominal composition Mg 2 (Si 1 − x Ti x )O 4 were investigated together with their microwave dielectric characteristics. MgSiO 3 secondary phase was observed in Mg 2 SiO 4 ceramics, and it could be suppressed by Ti-substitution. However, Mg 2 TiO 4 and MgTi 2 O 5 appeared gradually with increasing Ti-substitution amount. The dielectric constant slightly increased from 6.8 to 8.1 with Ti-substitution, and the Qf value was improved significantly and reached the maximum at x = 0.1 where the optimum combination of microwave dielectric characteristics were achieved: e r = 7.4, Qf = 73,760 GHz at 15 GHz, τ f = − 60 ppm/°C.