| 【文章摘要】 Yttrium oxyfuoride (YOF) is known for exhibiting superior plasma-resistance properties compared to Y2O3, particularly in a fuorocarbon plasma environment. The formation of the YOF layer directly on the surface of Y2O3 via surface modification may be considered as a viable and cost-effective method. In this study, we employed ammonium fluoride (NH4F) salt for the surface modification of Y2O3. By using a 40 wt% NH4F aqueous salt solution, the YOF layer with a thickness of about 8.6 μm was effcaciously formed in-situ on the surface of Y2O3 based on the fuorination mechanism. The composition and microstructure of the modified Y2O3 surface was thoroughly characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis revealed the formation of distinct intermediate ammonium yttrium fluoride phases depending upon the heat treatment temperature (150 500 ℃) through the fuorination of Y2O3 with NH4F. A stable YOF phase was formed ultimately at 300 ℃. Plasma etching tests were performed using a mixture of CF4/Ar/O2 gases for 1 h. The microstructures of specimens are observed by SEM before and after plasma treatments. Plasma exposure tests demonstrated that specimens heat-treated at 500 ℃ for 2 h exhibit excellent plasma-resistance behavior with minimal surface damage, which is attributed to the presence of stable and dense YOF phase. |