Effect of borate glass additives on the sintering behaviour and dielectric properties of BaTi4O9 ceramics

Effect of B2O3 and BaB2O4 addition on microwave dielectric characteristics and sintering behaviours of BaTi4O9 ceramics were investigated. When B2O3 was added, bulk density of the sintered sample decreased as the content of B2O3 increased. B2O3 addition induced complex reaction with BaTi4O9 and resulted in the development of second phases such as Ba2Ti9O20, BaTi(BO3)2 and TiO2. When BaB2O4 was added, however, relative density increased and the second phases of Ba2Ti9O20 and BaTi(BO3)2 were produced. Dielectric characteristics of BaTi4O9 were also discussed from the viewpoint of bulk density, microstructure and second phases.