抄録
The effects of particle size on the sintering of PbTiO3 containing a small amount of PbO-TiO2-Al2O3-SiO2 glass were investigated under various atmospheres.
The PbTiO3 powders with the average particle sizes of 0.27, 0.18 and 0.11 μm containing 0.01 wt% glass powder were pressed into pellets at 3 ton/cm2 and sintered at 1100-1200°C for 0.5-7 hrs in various atmospheres. All the sintered compacts had a grain size of 0.8-7.2 μm and a bulk density of 7.02-7.74 g/ cm3. The order of the sinterability in various atmospheres of PhTiOa was O2>PbO> air> N2. The green and sintered densities and the microstructures of compacts in the sintering process were affected by the particle size distribution of the PbTiO3 powder. The dielectric constant of the compacts depended on the sintered density, grain size and the variation of the composition with the evaporation of PbO in the sintering process. The best PbTiO3 compact having a density of 7.74 g/cm3 and a grain size of 1.8 μm was obtained from the 2.7 fsm powder by sintering at 1120°C for 1 hr in oxygen, and the dielectric constant at 1 MHz of this compact was 268 at room temperature.
