| 摘要: |
| 在H2+Ar等离子刻蚀后的C/C复合材料表面进行等离子渗Co和CoNiCrAlTaHfY共渗复合处理，形成CoNiCrAlTaHfY/Co多元复合涂层，通过与刻蚀前后制备的CoNiCrAlTaHfY涂层对比分析，研究了刻蚀与Co过渡层对CoNiCrAlTaHfY/Co复合涂层组织、成分及结合强度的影响。结果表明，刻蚀前、后形成的CoNiCrAlTaHfY涂层厚度分别为10 μm和14 μm。刻蚀处理后，原棒状炭纤维与紧密包裹其的碳基体分别被刻蚀成针状和薄壁管，在炭纤维与基体碳之间形成孔隙，比表面积也相应增大，促进元素形核和扩散，使涂层与基体结合强度增加。在刻蚀表面与CoNiCrAlTaHfY多元涂层间增加Co过渡层，形成的CoNiCrAlTaHfY/Co复合涂层厚约30 μm，复合涂层成分连续，组织均匀致密，由CrCoTa，Al2Ta，Cr2Ta，AlxCry，AlCo2Ta，Co，AlxNiy组成，Co过渡层与CoCrAlTaHfYNi表层分别以三维岛状和柱状生长。CoNiCrAlTaHfY表层/Co过渡层/基体间的互扩散导致涂层与基体间的结合力明显提高。 |
| 关键词: C/C复合材料 等离子渗金属 等离子刻蚀 Co过渡层 CoNiCrAlTaHfY/Co复合涂层 |
| DOI：10.11933/j.issn.1007-9289.20171101002 |
| 分类号:TG156.8;TG174.445 |
| 基金项目:国家自然科学基金（51474154，51501125，51601124） |
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| Microstructure of CoNiCrAlTaHfY/Co Composite Coating Formed on C/C Composites |
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GUO Qi, MENG Tian-xu, XI Wen, DING Wen-qiang, YU Sheng-wang, LIU Xiao-ping
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School of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024
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| Abstract: |
| The CoNiCrAlTaHfY/Co composite coatings were prepared in H2+Ar etched surface of C/C composites by duplex plasma alloying of Co and CoNiCrAlTaHfY. Effects of etching and Co transition layer on the microstructure, composition and bonding strength of CoNiCrAlTaHfY/Co composite coatings were investigated by comparing with CoNiCrAlTaHfY coatings formed on C/C composites. The results show that the thickness of CoNiCrAlTaHfY coatings with and without etching is 10 μm and 14 μm respectively. After the etching process, the original rod-like carbon fibers and the carbon substrate tightly wrapped are respectively etched into needle-like manner and thin-walled tubes, forming pores between the carbon fibers and the substrate carbon. The increased specific surface area promotes the nucleation and diffusion of the elements, improving the bonding between the coating and the substrate. The CoNiCrAlTaHfY/Co composite coatings of 30 μm are formed on etched C/C composites after adding the Co transition layer. The compact composite coatings are composed of CrCoTa, Al2Ta, Cr2Ta, AlxCry, AlCo2Ta, Co and AlxNiy. The Co transition layer and the CoNiCrAlTaHfY top layer grow in a columnar manner and three-dimensional island respectively. The mutual diffusion among the CoNiCrAlTaHfY toplayer/Co transition layer/substrate results in a stronger adhesion between the coating and the substrate. |
| Key words: C/C composites plasma alloying plasma etching Co transition layer CoNiCrAlTaHfY/Co composite coating |
