陶瓷材料微波加工用高均匀度多模谐振腔的研究

微波能作为一种新型能源，用于陶瓷材料的加工具有广阔的应用前景。如何改善微波加热时的均匀性，是实现微波加工陶瓷的关键技术之一。基于旋转场天线原理，建立了一种新型的多模谐振腔。采用了３ｄＢ桥及相互垂直的耦合孔，从而在谐振腔内形成旋转的电磁场，大大改善了加热均匀性。与频率２４５０ＭＨｚ、输出功率５ｋＷ的微波源相配合，建立的加热系统结构简单，加热特性优良，尤其适合于大尺寸陶瓷材料的微波加工。对Ａｌ２Ｏ３，ＺｒＯ２，Ｓｉ３Ｎ４等先进陶瓷成功地进行了烧结。

Study on the multimode cavity with high uniformity used for microwave processing of ceramics

The use of microwave power as an alternative energy source for processing ceramic materials offers great potential for future application. It is one of the key points how to improve the heating uniformity for microwave processing of ceramics. A new type of multimode cavity with a 3dB bridge and two coupling apertures perpendicular to each other has been established based on the principle of rotating field. A rotating electromagnetic field is formed inside the cavity, so it greatly improves the heating uniformity. The heating system which consists of the cavity and a 5 kW variable power microwave source operating at 2450 MHz is characterized by simple construction, high efficiency and good performance, so it is suitable for microwave processing of large sized ceramic workpieces. Advanced ceramic materials, such as Al 2O 3, ZrO 2, Si 3N 4, etc, have been sintered successfully using the new system.