新型的Sol-gel法制备Ba0．6Sr0．4TiO3铁电陶瓷

Characterization of Barium Strontium Titanate Bulk Ceramics Fabricated Using a New Sol-gel Based Process

采用新型的Sol-gel工艺制备了Ba0．6Sr0．4TiO3（BST）超细粉体，将BST粉体进行压制和烧结，获得了晶粒尺寸在1μm以内的BST陶瓷块体。观察了BST陶瓷块体的结晶情况并测定了其电学性能。在Sol—gel工艺中，加入了有机大分子量聚乙烯吡咯烷酮（polyvinyl pyrrolidone，PVP）制备BST前驱体。实验结果表明：PVP的加入可有效增加前驱体的稳定性和分散性，降低BST陶瓷的预烧温度约250℃，并在1200℃获得晶粒细小、致密的BST陶瓷。BST陶瓷，显示弥散相变特征。

The ultra-fine powder of Ba0.6 Sr0.4TiO2 （BST）is fabricated by a new Sol-gel method and sintering. The BST ceramic with fine grains（-1μm）can be obtained. Their crystallization and electrical properties are investigated. In this new Sol-gel method, higher-molecular-weight PVP is more effective in increasing the stability and dispersivity of the BST procedure. The experimental results show that the calcining temperature of Sol-gel derived powder could be lowered about 250℃ ,dense ceramic with homogeneous grain size is obstained at 1200℃, good electric properties and obvious characteristics of diffused phase transition.