多孔陶瓷的直写成型工艺研究进展

多孔陶瓷内部含有大量三维孔隙，具有轻质、高强、高比表面积、低导热系数等特性，但是多孔陶瓷的传统制备工艺对结构和性能的可控性较低，很难满足先进能源、航空航天、电子信息等领域的发展对多功能高性能材料的需求。直写成型工艺是一种制造成本低、材料使用性广、技术可拓展性高的3D打印工艺，不仅可以直接制备具有轻量化特点的多孔陶瓷，而且结合其他工艺可以实现多孔陶瓷的层级结构和多功能化，有望实现设计与制造、材料与器件、结构与功能的一体化。介绍了直写成型法3D打印多孔陶瓷的工艺原理，综述了直写成型法直接制备多孔陶瓷、直写成型结合乳液/泡沫法和冷冻干燥法制备层级多孔陶瓷的研究进展。由于工艺柔性高，直写成型法能够与其他方法良好融合，以制备具有特殊结构和性能的多孔材料，尤其是兼顾高强度、高孔隙率和形状可控性的层级多孔陶瓷。最后，总结了目前直写成型工艺制备多孔陶瓷的优势和不足，并对打印材料性能、打印设备和主要应用领域的发展进行了展望。

Research Progress in Direct Ink Writing Process of Porous Ceramics

Due to a large number of three-dimensional pores inside, porous ceramics is characterized by lightweight, high-strength, high specific surface area, and low thermal conductivity. However, the traditional preparation processes of porous ceramics have a low controllability of structures and properties, which is difficult to meet the requirements of the development of advanced energy, aerospace, electronic information and other fields for multi-functional high-performance materials. Direct ink writing (DIW) is a 3D printing process with low cost, wide application of materials, and high expansibility. DIW process can not only directly prepare lightweight porous ceramic, but also realize the hierarchical structure and multi-function of porous ceramics in combination with other processes. It is expected to realize the integration of design and manufacturing, material and device, structure and function. The principle of 3D printing of porous ceramics by DIW was introduced. The research progress of DIW methods for porous ceramics, DIW combined emulsion/foam or freezing drying methods for hierarchical porous ceramics was reviewed. Due to the high flexibility of the process, DIW process could be well integrated with other methods to prepare porous materials with special structure and properties, especially the hierarchical porous ceramics with high strength, high porosity and shape controllability. At last, the advantages and disadvantages of the preparation of porous ceramics by DIW process were summarized, and the development of printing materials, printing equipment and main application fields were prospected.