| 摘要: |
| 采用多弧离子镀技术在Ti-6Al-4V合金基底表面依次沉积Al层和NiCrAlY涂层，对比研究Ti-6Al-4V合金和NiCrAlY/Al复合涂层在高温腐蚀 (500 ℃, 30 h) 过程中微观组织结构变化及其抗高温腐蚀性能。经测定，NiCrAlY/Al复合涂层中Al层的厚度约为270 nm，NiCrAlY涂层的厚度约为3.8 μm。高温腐蚀测试结果显示，Ti-6Al-4V合金表面出现点蚀，腐蚀区域出现大量裂纹，表明合金发生严重的高温腐蚀。表面沉积NiCrAlY/Al复合涂层的Ti-6Al-4V合金经高温腐蚀后表面依然完整，未产生明显裂纹和涂层脱落。经分析，NiCrAlY/Al复合涂层在高温腐蚀过程中表面可自形成厚度约为43 nm的Al2O3和Cr2O3，连续且致密的薄氧化膜可在高温下阻隔氧气向钛合金内部的侵蚀，从而显著提高基底合金的抗高温腐蚀性能。 |
| 关键词: 多弧离子镀 NiCrAlY/Al复合涂层 微结构 抗热腐蚀性能 |
| DOI：10.11933/j.issn.1007-9289.20190402001 |
| 分类号:TG174.44 |
| 基金项目:国家重大科技专项(2017-VII-0012-0107)；宁波市科技创新重大专项(2018B10019，2015B11055) |
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| High Temperature Corrosion Resistance of NiCrAlY/Al Composite Coatings on Surface of Ti-6Al-4V Alloy |
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REN Xueru1,2, SHI Lei2, MAO Jinming3, LI Jinlong1
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1.Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China;2.Nano Science and Technology Institute, University of Science and Technology of China, Suzhou 215123, China;3.Zhejiang Fashion Institute of Technology, Ningbo 315201, China
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| Abstract: |
| Al layer and NiCrAlY coating were sequentially deposited on the surface of Ti-6Al-4V alloy substrate by multi-arc ion plating. The microstructure variation and high temperature corrosion resistance of Ti-6Al-4V alloy and NiCrAlY/Al composite coating were also comparatively investigated during the high temperature corrosion (500 ℃, 30 h). NiCrAlY/Al composite coating was composed of the inner layer of Al and the NiCrAlY with the thickness of about 270 nm and 3.8 μm, respectively. Results of high temperature corrosion test show that the surface of the Ti-6Al-4V alloy exhibits cracks around pitting corrosion areas, exhibiting the severe high temperature corrosion. Conversely, NiCrAlY/Al composite coating is intact and no obvious cracks and coating peeling are observed. In the process of high temperature corrosion, NiCrAlY/Al composite coating can self-form Al2O3 and Cr2O3 film with thickness of about 43 nm, which can inhibit the penetration of oxygen and thereby avoid substrate corrosion. Thus, the high temperature corrosion resistance of Ti-6Al-4V alloy is significantly improved by NiCrAlY/Al composite coating. |
| Key words: multi-arc ion plating NiCrAlY/Al composite coating microstructure hot corrosion resistance |
