Open AccessEffects of Nd 2 O 3 and TiO 2 Addition on the Microstructures and Microwave Dielectric Properties of BaO‐Nd 2 O3‐TiO 2 System
Author(s) -
Kim TaeHong,
Park JungRae,
Lee SukJin,
Sung HeeKyung,
Lee SangSeok,
Choy TaeGoo
Publication year - 1996
Publication title -
etri journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.295
H-Index - 46
eISSN - 2233-7326
pISSN - 1225-6463
DOI - 10.4218/etrij.96.0196.0012
Subject(s) - microstructure , dielectric , materials science , sintering , temperature coefficient , ceramic , microwave , mineralogy , analytical chemistry (journal) , composite material , chemistry , chromatography , physics , optoelectronics , quantum mechanics
The effects of Nd 2 O 3 and TiO 2 addition on the microstructures and microwave dielectic properties of BaO‐Nd 2 O 3 ‐TiO 2 system were investigated. BaNd 2 Ti 4 O 12 or BaNd 2 Ti 5 O 14 phases were observed for compositions based on BaO/Nd 2 O 3 = 1 ratio. The compositions deviated from BaO/Nd 2 O 3 = 1 ratio were composed of major phases of BaNd 2 Ti 4 O 12 or BaNd 2 Ti 5 O 14 , and the compound of Nd 2 O 3 and TiO 2 (Nd 2 Ti 2 O 7 ) or that of BaO and TiO 2 (BaTi 4 O 9 ). The microstructure of ceramic with BaO·Nd 2 O 3 ·4TiO 2 composition varied from spherical grains to needlelike grains with increasing sintering temperature. With increasing Nd 2 O 3 , the optimum sintering temperature with maximum density increased, and the dielectric constant( · r ) and quality factor(Q) decreased due to the formation of secondary phases. With increasing TiO 2/ the optimum sintering temperature and the dielectric constant decreased with increased Q value. And the temperature coefficient of resonant frequency, · f shifted toward positive direction. The dielectric ceramics with BaO/Nd 2 O 3 = 1 showed Q values of above 2000 and dielectric constants of above 80 at 3GHz.