摘要
通过机械合金化及冷喷涂在镍基高温合金(IN738)基体上制备Ni/Al复合涂层。在保护气氛Ar中热扩散制备NiAl金属间化合物涂层。为了研究致密化对NiAl涂层的抗氧化性能的影响,对NiAl金属间化合物涂层及经过喷丸工艺和在1080℃下10h的热处理获得的NiAl致密化涂层进行了等温氧化试验。将试样在1020℃下分别进行1h、10h和200h的氧化,采用X射线衍射仪和扫描电子显微镜分析了高温氧化后涂层的组织结构。结果表明,NiAl涂层高温氧化过程中涂层表面氧化膜剥落情况比较严重,1020℃高温氧化10h时有明显的氧化膜剥落现象,但涂层内部氧化随高温氧化的时间变化不大。致密化处理后NiAl涂层没有发生明显的氧化,并表现出了很好的抗氧化性能,在1020℃高温氧化200h后,涂层内部仍然没有发生明显的氧化。
The Ni/Al coatings were prepared by cold spraying of ball-milled Ni/Al alloy powders. The NiAl/ ZrC coating was prepared by heat diffusion using Ar as protection gas and the oxidation resistance of the coating was determined by the isothermal oxidation at 1020 ℃ for 1 h, 10 h and 200 h. The microstructure of the NiAl coating af- ter high temperature oxidation was characterized by scanning electron microscopy and X-ray diffraction analysis. The results showed that the oxide film was discovered at 1020 ℃ for 10 h. The oxidation of NiAl coating could not be found. The NiAl coating had good oxidation resistance. There was no obvious oxidation in coating under 1020 ℃ for 200 h.
基金
国家重点基础研究计划(2007CB707702)
关键词
冷喷涂
NIAL涂层
高温氧化
致密化
cold spraying
NiAl coating
high temperature oxidation
desification
