中文摘要：

利用电弧离子镀技术在DSM11合金基体上制备含或不含扩散阻挡层（diffusion barrier,DB）的Ni Cr Al YSi涂层,对比研究2种涂层在900℃恒温热腐蚀行为和从900℃到室温的循环热腐蚀行为（表面混合盐质量分数为75%Na2SO4＋25%K2SO4）。研究结果表明：在恒温热腐蚀条件下,含或不含扩散阻挡层的Ni Cr Al YSi涂层表面主要生成了α-Al2O3和γ/γ′相;腐蚀100 h后,Ni Cr Al YSi涂层出现了较多的Kirkendall孔洞,基体与涂层元素的互扩散明显。Ni Cr Al YSi/DB涂层的扩散阻挡层可有效地抑止基体与涂层的元素互扩散,防护效果比单一Ni Cr Al YSi涂层的效果好。在循环热腐蚀条件下,含或不含扩散阻挡层的Ni Cr Al YSi涂层表面主要生成α-Al2O3、尖晶石、Ti O2和γ/γ′相;腐蚀100 h后,Ni Cr Al YSi涂层内氧化和内硫化现象严重,Ni Cr Al YSi/DB涂层的扩散阻挡层界面易开裂,影响扩散阻挡层的效力,导致涂层体系比单一Ni Cr Al YSi涂层更快失效。

英文摘要：

The Ni Cr Al YSi coatings with or without a diffusion barrier（DB） were prepared on a Ni-based superalloy DSM11 by arc ion plating technique. The hot corrosion behaviors of two kinds of the coatings under different conditions in molten 75% Na2SO4＋25% K2SO4（mass fraction） at 900 ℃ or 900 ℃ to room temperature were investigated and compared. The results show that during the isothermal hot corrosion, α-Al2O3 and γ/γ′ phases are formed on the Ni Cr Al YSi coating with or without a DB. After 100 h, Ni Cr Al YSi coating shows Kirkendall voids and the interdiffusion between the coating and substrate is obvious. Ni Cr Al YSi coating with a DB significantly suppresses the interdiffusion between the coating and substrate, and the defending effect is better than that of Ni Cr Al YSi coating without a DB. During the cyclic hot corrosion, the Ni Cr Al YSi coating with or without a DB consists of α-Al2O3, spinels,Ti O2 and γ/γ′ phases. After 100 h, Ni Cr Al YSi coating presents the severe internal oxidation and sulfidation. The interface of barrier layer is prone to cleavage and will reduce its efficiency, which causes the Ni Cr Al YSi coating with a DB to display the earlier failure than the Ni Cr Al YSi coating without a DB.