Low‐Fire Processing (Ca 1− x Nd 2 x /3 )TiO 3 Microwave Ceramics

Effects of 3ZnO·2B 2 O 3 (3Z2B) glass addition on densification and microwave properties of (Ca 1− x Nd 2 x /3 )TiO 3 (CNT‐X) have been investigated. With the 3Z2B glass content greater than 20 vol%, the densification temperature can be greatly reduced from 1400°C for pure CNT‐X to 850°–900°C for CNT‐X + 3Z2B microwave ceramics. The above result is attributed to a chemical reaction taking place at the interface of 3Z2B/CNT‐X during firing. The Ca in CNT‐X dissolves into 3Z2B, forming a new glass of CaO‐ZnO‐B 2 O 3 at 870°–880°C which enhances the densification kinetics of 3Z2B + CNT‐X microwave ceramics. For the samples with 20–40 vol% 3Z2B, the resulting 3Z2B + CNT‐X microwave ceramics have a dielectric constant ( k ) of 30–60 and a quality factor ( Q ) of 200–550 at 1–10 GHz, and a temperature coefficient of resonant frequency of 20–60 ppm/K in the temperature range of 20°–80°C.