화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.86, No.1, 93-98, 2003
Low-fire processing (Ca1-xNd2x/3)TiO3 microwave ceramics
Effects of 3ZnO.2B(2)O(3) (3Z2B) glass addition on densification and microwave properties of (Ca1-xNd2x/3)TiO3 (CNT-X) have been investigated. With the 3Z2B glass content greater than 20 vol%, the densification temperature can be greatly reduced from 1400degreesC for pure CNT-X to 850degrees-900degreesC 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-B2O3 at 870degrees-880degreesC 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 20degrees-80degreesC.