| 摘要 |
Fine-grain semiconducting internal boundary layer ceramic compositions are prepared by mixing a finely divided alkaline earth metal titanate powder, which has been made semiconducting by doping with an n-type semiconductor forming material, with a minor amount of a liquid phase sintering agent selected from (1) boric oxide (B2O3) or (2) a mixture of boric oxide with one or more oxides of copper, bismuth, silicon, iron, lead, potassium, sodium and phosphorous, and firing at a temperature of about 900-1300 DEG C for 1-100 minutes. The resulting composition is a fine-grain, two-phase ceramic having a discrete or discontinuous phase consisting of the semiconducting alkaline earth metal titanate surrounded by a continuous intergranular phase forming a boundary layer which insulates the grains of the titanate. |
