等离子喷涂-物理气相沉积制备纳米复合结构环境障涂层及热循环性能研究

Nano-composite Structured Environmental Barrier Coatings Prepared by Plasma Spray-Physical Vapor Deposition and Its Thermal Cycle Performance

摘要:

在SiC/SiC陶瓷基复合材料(CMC)上制备了具有三层结构(Si/Mulltite/Yb2SiO5)的环境障涂(EBCs)。提出了一种新的等离子喷涂-物理气相沉积(PS-PVD)制备EBCs的方法来减少SiC/SiC 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，还测试了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。

关键词:环境障涂层,等离子喷涂-物理气相沉积,热循环,Yb2SiO5

Abstract:

Environmental barrier coatings (EBCs) consisting of a tri-layer structure (Si/Mulltite/ Yb₂SiO₅) were prepared on SiC/SiC ceramic matrix composite (CMC). For decreasing degradation of water-oxygen corrosion for SiC/SiC 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 were 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 water. No apparent spallation appeared after 30 cycles, which showed the EBCs had a good thermal shock performance.

Key words:EBCs, PS-PVD,Thermal cycle,Yb2SiO5