基于高温高可靠性掺杂Ti3SiC2连接铬酸镧陶瓷的界面调控及稳定机制研究

Lanthanum chromite (LaCrO3) has potential application in heating element and fuel cell as a kind of high temperature structure - functional ceramic material. however, it has some drawbacks such as high strength decentralization, poor formability and poor processability, resulting in its limited development and application. Therefore, it is necessary to develop the joining technology of LaCrO3 materials. In order to meet the industrial application demands, developing novel interlayer materials and joining technology, which has low joining temperature and easy operability, are highly appreciated for the LaCrO3 ceramic joints. In this project, LaCrO3 ceramic will be joined by molten salt-SPS in-situ technology together, using modified Ti3SiC2 nano material as an interlayer material. The controllable preparation of modified Ti3SiC2 and the control mechanism of joining technology and microstructures of LaCrO3 joining will be studied. The mechanical and electrical properties will be revealed for the LaCrO3 joint with modified Ti3SiC2 as an interlayer. The design method and criterion of LaCrO3 joint with modified Ti3SiC2 by molten salt and in-situ SPS technology will be established.

铬酸镧陶瓷作为一种高温结构-功能陶瓷材料，在加热元件、燃料电池等方面有应用潜力，但其强度分散性大，成型性差，加工性差等限制了它的发展和应用，因此利用连接技术对铬酸镧陶瓷元器件进行制作和修复对拓展材料的应用显得极为必要。本项目旨在开发连接温度低、容易操作且能使陶瓷连接件在高温下保持高性能的纳米中间层以及连接工艺。以铬酸镧陶瓷连接件高温下的优良性能为目标，采用掺杂Ti3SiC2纳米材料作为中间层通过熔盐-SPS原位技术连接铬酸镧陶瓷，研究掺杂Ti3SiC2纳米中间层的可控制备，铬酸镧陶瓷连接工艺及微观结构的调控机制，揭示掺杂Ti3SiC2纳米中间层微观结构与连接件力学性能、电性能的内在关联机制。建立掺杂Ti3SiC2纳米材料作为连接中间层连接铬酸镧陶瓷的设计方法与准则。

铬酸镧陶瓷作为一种高温结构-功能陶瓷材料，在加热元件、燃料电池等方面有应用潜力，但其强度分散性大，成型性差，加工性差等限制了它的发展和应用，因此利用连接技术对铬酸镧陶瓷元器件进行制作和修复对拓展材料的应用显得极为必要。本项目选用了掺杂Ti3SiC2及其复合材料和ZrB2复合材料等四种材料作为中间层通过SPS技术进行了铬酸镧陶瓷的连接，通过XRD、SEM、TEM和EDS等对中间层及连接件进行了表征，系统研究了中间层材料及其铬酸镧连接件的物相组成、显微结构、力学性能等。对四种中间层材料进行了可控制备研究，结果表明，通过可控制备均可获得与铬酸镧材料热膨胀性能接近的中间层。进一步采用四种中间层进行了铬酸镧陶瓷的连接研究，分析了中间层材料连接铬酸镧陶瓷的连接工艺及微观结构的调控机制，揭示了中间层物相组成、微观结构与连接件力学性能、电性能的内在关联机制。项目的研究结果对拓展铬酸镧材料的应用具有一定的指导意义。