Low-Temperature Firing and Microwave Dielectric Properties of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− Ceramics with ZnB2O4 Glass Addition
Abstract:Low-temperature sintered Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− microwave dielectric ceramics with ZnB2O4 glass (ZBG) addition were prepared by the conventional solid state reaction method. The sintering behavior, microstructure, and microwave dielectric properties of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− ceramics with ZBG addition were investigated. The ZBG addition lowered the densified temperature of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− ceramics from 1150°C to 940°C. The dielectric constants of Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− ceramics decreased from 40 to 34 and the temperature coefficient of resonant frequency (f) changed gradually from +12.7 to −25.7 ppm/°C as ZBG addition increased from 0 to 8 wt%. The Qf values increased greatly from 20,500 GHz of pure Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− to 26,900 GHz when 5 wt% ZBG was added. Ca[(Li1/3Nb2/3)0.8Ti0.2]O3− ceramics with 8 wt% ZBG addition sintered at 940°C show good microwave dielectric properties with r∼32.5, Qf∼20,600 GHz, and f∼−25.7 ppm/°C. The relationship between dielectric properties and microstructure was also discussed.
Document Type: Research Article
Affiliations: Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049, China
Publication date: July 1, 2008