【摘要】 在SiC/SiC陶瓷基复合材料（CMC）上制备了具有3层结构（Si/Mullite/Yb₂SiO₅）的环境障涂层（EBCs）。提出了一种新的等离子喷涂-物理气相沉积（PS-PVD）方法制备EBCs以减少Si C/Si C CMC在水氧腐蚀下的降解。在制备EBCs之前,用喷雾干燥塔制备了团聚的Yb₂SiO₅粉末。然后通过PS-PVD技术制备了致密的EBCs,得到了具有层状和柱状复合结构的Yb₂SiO₅涂层,并给出了这种特殊结构的沉积示意图。此外,测试了PS-PVD制备的EBCs在1300℃到室温水中的热循环性能。在30次热循环实验后未出现明显的散裂现象,表明EBCs具有良好的抗热震性能。更多还原

【Abstract】 Environmental barrier coatings（EBCs） consisting of a tri-layer structure（Si/mullite/Yb₂SiO₅） were prepared on Si C/Si C ceramic matrix composite（CMC）. For decreasing the degradation of water-oxygen corrosion of Si C/Si C CMC, a novel EBCs fabrication method of plasma spray-physical vapor deposition（PS-PVD） was proposed in this work. Prior to EBCs preparation, agglomerated Yb₂SiO₅ powders was fabricated by spray dryer. After that, dense EBCs were fabricated by PS-PVD technique, where the Yb₂SiO₅ coating with laminar and columnar composited structure was achieved. And the deposition diagram of this special structure was presented. Besides, the thermal cycle performance of PS-PVD EBCs was tested from 1300 ℃ to room temperature in water. Results show that no apparent spallation appears after 30 cycles, indicating that the EBCs have a good thermal shock performance.更多还原