((1. 上海交通大学 金属基复合材料国家重点实验室,上海 200240;2. 北京科技大学 北京市腐蚀、磨蚀与表面技术重点实验室,北京 100083;3. 河北科技大学 材料学院,石家庄 050054))
摘 要:
关键字: 铝化物涂层;Q235钢;电脉冲沉积;微晶化涂层;高温腐蚀
((1. State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China; 2. Beijing Key Laboratory for Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China;3. School of material, Hebei University of Science and Technology, Shijiazhuang 050054, China))
Abstract:Vibrating electro-spark deposition equipment is developed to prepare metal coatings with high deposition efficiency. An Fe-Al intermetallic compound layer is formed by the high temperature plasma during the instant discharge between Al electrode and specimen. The coatings formed on Q235 steel possess microcrystalline structure, with a thickness about 100 m. The micro-crystal line structure is achieved due to the high cooling rate during deposition. The quality of the coatings is enhanced by using Ar to protect samples from oxidation. The coatings are metallurgically bonded to the substrate without obvious interface. The samples with aluminide coatings for oxidation were put in air at 600 ℃ for 200 h, and those for sulfuration were put in flowing 99.98% SO2 at 600℃ for 50 h, and then SEM, EDS and XRD analyses were performed to understand the oxidation and sulfuration mechanisms of the coatings. The results show that the high temperature oxidation and sulfuration resistance of samples with aluminide coatings are improved remarkably.
Key words: iron aluminide coating; Q235 steel; electro-pulse deposition; microcrystalline structure; high temperature corrosion