织构化无铅压电陶瓷体系及制备工艺研究进展

Research Progress of Textured Lead-Free Piezoelectric Ceramics Systems and Preparation Technology

随着环境友好型材料的提出和可持续发展的要求,各个领域对于无铅压电材料的需求越来越大,高性能无铅压电陶瓷的研究与开发成为国内外压电材料研究的热点。研究表明,在某一极化方向拥有高度晶粒取向（高织构度）的压电陶瓷表现出的压电性能大幅优于非织构化陶瓷,如何将无规则排列的陶瓷晶粒定向排列形成织构陶瓷,是近些年的研究热点与难点。该综述主要介绍了目前研究广泛的几种主要的无铅压电陶瓷体系：铌酸钠钾（KNN）基陶瓷、钛酸钡（BT）基陶瓷、钛酸铋钠（BNT）基陶瓷、铋层状陶瓷以及钨青铜结构陶瓷,并综述了无铅压电陶瓷的主要制备技术,着重介绍了晶粒定向技术的相关进展：热处理技术、定向凝固技术、磁场定向技术、模板晶粒生长（TGG）技术、反应模板晶粒生长（RTGG）技术以及多层晶粒生长（MLGG）技术。同时,综述了多种织构化成型工艺：干压成型、丝网成型、轧膜成型、挤出成型、热锻成型以及流延成型。

With the development of sustainable development and environmental friendly material requirements, the demand for lead-free piezoelectric materials is more and more widely, the research and development of high performance lead-free piezoelectric ceramics has become a hot research topic on piezoelectric materials at home and abroad. Researches show that the high degree of grain orientation in a polarization direction （high texture） piezoelectric ceramics exhibit piezoelectric properties significantly better than non textured ceramics, it is a hot spot and difficulty in recent years that how to arrange the randomly arranged ceramic grains to form the texture ceramics. This review mainly introduces several widely studied main lead-free piezoelectric ceramics system： KNN ceramics, BT ceramics, BNT ceramics, bismuth layered ceramics, tungsten bronze structure ceramics, and summarizes the main lead-free piezoelectric ceramics preparation process, emphatically introduces the related progress of grain orientation techniques： heat treatment technology, directional solidification technology, field oriented technology, templated grain growth （TGG） technology, reactive templated grain growth （RTGG） technology, multi-layer grain growth （MLGG） technology. At the same time, a variety of texturing technologies are reviewed including dry pressing, screen printing method, roll method, extrusion method, hot-forging method and tape-casting method.