| 摘要: |
| 高温耐磨涂层是航空发动机关键摩擦副可靠使用的重要保障，鉴于其服役环境日益严苛复杂，进一步提高涂层的高温耐磨性能是十分必要的。利用激光辅助热喷涂技术制备 NiCoCrAlYTa / ZrO2 / BaF2·CaF2 高温耐磨涂层，利用 SEM、EDS 分析高温耐磨涂层的横截面微观组织及化学成分，研究 ZrO2 / BaF2·CaF2质量分数、激光功率及扫描速度对耐磨涂层微观组织、力学性能及高温耐磨性能的影响。结果表明：激光辅助处理可以诱导耐磨涂层表面形成具有树枝状结构的 ZrO2陶瓷层； 当激光功率为 80 W，扫描速度为 8 mm / s，喷涂粉末为 75 wt.% NiCoCrAlYTa+25 wt.% ZrO2 / BaF2·CaF2时，制备涂层的微观组织、综合力学性能及高温耐磨性能达到最好；在此工艺参数下，涂层顶部的 ZrO2 陶瓷层最为致密均匀，其平均纳米硬度为 13.6 GPa，平均弹性模量为 182.5 GPa，800 ℃时的磨损率为 2.7×10-5 mm3 ·N-1 ·m-1 。将高温耐磨涂层的组分设计与激光辅助热喷涂工艺相结合，可为提高涂层综合性能的提供解决途径。 |
| 关键词: 激光辅助热喷涂 NiCoCrAlYTa / ZrO2 / BaF2·CaF2涂层 力学性能 高温磨损 |
| DOI：10.11933/j.issn.1007-9289.20211031002 |
| 分类号:TG156;TB114 |
| 基金项目:国家科技重大专项资助项目(2017- VII -0013-0110) |
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| Microstructure and Properties of Laser-assisted Thermal Spraying NiCoCrAlYTa / ZrO2 / BaF2·CaF2 Coating |
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WANG Changiang1, CHEN Haohui2, ZHANG Mei3, YANG Jiaoxi4, ZHANG Ang1, LIANG Shuaishuai5
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1.Aviation Key Laboratory of Science and Technology on Advanced Corrosion and Protection forAviation Materials, AECC Beijing Institute of Aeronautical Materials, Beijing 100095 , China;2.Unit 3238 2.of PLA, Beijing 100072 , China;3.School of Materials Science and Engineering, Beihang University, Beijing 100191 , China;4.Institute of Laser Engineering, Faculty of Material and Manufacturing, Beijing University of Technology,Beijing 100124 , China;5.School of Mecharical Engineering, University of Science and Technology Beijing, Beijing 100083 , China
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| Abstract: |
| High-temperature wear-resistant coatings are reliable guarantees of key friction pairs of aeroengines, and it is urgent to further improve wear resistance of the coatings under increasingly harsh service conditions. Therefore, the NiCoCrAlYTa / ZrO2 / BaF2·CaF2 high-temperature wear-resistant coatings are prepared by laser-assisted thermal spraying technology and the microstructure evolution with the chemical composition analysis are studied by SEM coupled with EDS techniques. Moreover, the effects of the mass fraction of ZrO2 / BaF2·CaF2, laser power and scanning speed on the microstructure,mechanical properties as well as high-temperature wear behaviors of the NiCoCrAlYTa / ZrO2 / BaF2·CaF2 coatings are investigated. Results show that the laser-treated coatings exhibit ZrO2 ceramic layers with dendritic microstructure on the top of the coatings. Particularly, the coating containing 25 wt.% ZrO2 / BaF2·CaF2, prepared by laser power of 80 W and scanning speed of 8 mm / s, exhibits optimum performance. And with the optimized parameters, the coating exhibits dense and uniform microstructure, the average value of hardness and elastic modulus could reach 13.6 GPa and 182.5 GPa, respectively, and wear rate could reach 2.7×10-5 mm3 ·N-1·m-1 after sliding under 800 ℃. Also, the methodology of combining the component design and preparation process of high-temperature wear-resistant coatings provides a reference for properties of coatings. |
| Key words: laser-assisted thermal spraying technology NiCoCrAlYTa / ZrO2 / BaF2 · CaF2 coating mechanical properties high-temperature wear |
