抄録
Many lead-free materials, such as Bi-based compounds, BaTiO3 or alkaline niobate compound, have been intensively studied. The microstructure and characteristics of BaTiO3 ceramic are significantly influenced by addition of 4PbO-B2O3. Under low sintering temperatures, the grain growth of BaTiO3 ceramic is enhanced by capillary action, rearrangement and solution-reprecipitation of the liquid phase. At high sintering temperatures, exaggerated grain growth of BaTiO3 ceramic is restrained by the presence of a liquid phase. The glass frit also has significant effect on the dielectric and piezoelectric properties of BaTiO3 ceramic. The measured density of BaTiO3 ceramic with suitable addition of 4PbO-B2O3 glass frit and sintering temperature can get 95.7-98.8% dense. The peak value of the KT33 was 2500 with addition of 0.2 mol% glass frit at the sintering of 1250°C for 4 h. The maximum value of the kp was 0.36 with addition of 0.2 mol% glass frit at the sintering of 1350°C for 4 h. With suitable amounts of glass frit and an optimized sintering temperature, the density is enhanced and the values of the dielectric and piezoelectric properties are improved.
