| 引用本文: | 刘思思,杨正航,武云文,廖君慧,刘金刚.超音速火焰喷涂Ni-CeO2复合涂层的数值模拟及耐磨耐腐蚀性能*[J].中国表面工程,2023,36(3):180~192 |
| LIU Sisi,YANG Zhenghang,WU Yunwen,LIAO Junhui,LIU Jingang.Numerical Simulation and Abrasion and Corrosion Resistance Properties of HVOF Ni-CeO2 Composite Coatings[J].China Surface Engineering,2023,36(3):180~192 |
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| 摘要: |
| 超音速火焰喷涂因其制备的涂层具有优异性能而被航空航天、石油化工等领域广泛使用，其工艺参数较为复杂且对涂层质量具有重要影响，但对其制备 Ni 基涂层的工艺参数选择及涂层性能研究相对较少。采用数值模拟的方法对超音速火焰喷涂 Ni 基涂层进行模拟，并对焰流与粒子特性进行分析；利用模拟指导试验，在 316L 不锈钢基体上成功制备 Ni-CeO2复合涂层；对复合涂层组织形貌及耐磨耐腐蚀性能做进一步研究。研究结果表明：当氧气煤油比等于 3，注入颗粒粒径在 20~80 μm 时，喷涂工艺最优；在添加 CeO2 后，复合涂层的耐磨性能耐腐蚀性能均得到提升，且当 CeO2 含量为 1 wt.%时，涂层硬度最大，摩擦因数最低，其摩擦因数相较于基体降低了 39.8 %，相较于 Ni 基涂层降低了 22.2 %，其耐磨性能相较于 Ni 基涂层提升了 62.5%。探究了超音速火焰喷涂工艺参数对喷涂系统状态的影响，分析了添加 CeO2在复合涂层中的作用，对超音速火焰喷涂 Ni-CeO2复合涂层具有引领与推动作用。 |
| 关键词: 超音速火焰喷涂 复合涂层 CeO2 数值模拟 耐磨性能 |
| DOI：10.11933/j.issn.1007?9289.20220729001 |
| 分类号:TH117;TG174 |
| 基金项目: |
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| Numerical Simulation and Abrasion and Corrosion Resistance Properties of HVOF Ni-CeO2 Composite Coatings |
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LIU Sisi1,2, YANG Zhenghang1, WU Yunwen1, LIAO Junhui3, LIU Jingang1,2
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1.School of Mechanical Engineering and Mechanics, Xiangtan University, Xiangtan 411105 , China;2.Hunan Provincial Key Laboratory of Vehicle Power and Transmission System, Xiangtan 411105 , China;3.Hunan Jiangbin Machinery (Group) Co.Ltd, Xiangtan 411105 , China
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| Abstract: |
| Stainless steel materials are extensively used in aerospace, petrochemical, nuclear, medical, and health fields because of their strong corrosion resistance, high heat resistance, and excellent plasticity. However, extremely high frictional wear is a main form of failure of stainless steel materials. High-velocity oxygen-fuel(HVOF), as a common surface treatment technology, has obvious advantages in strengthening the wear resistance of metal surfaces. However, HVOF parameters are complex and have a great influence on the coating quality. Numerical simulations of HVOF Ni coatings were performed by ANSYS software to simulate the trajectory of different particle size powder particles in the spraying process and the effect of different oxygen–fuel ratio (O / F) on the flame flow and particle state in the spraying process was investigated to obtain the spraying parameters with the best particle deposition state in the spraying process. Ni-CeO2 composite coatings with different CeO2 contents were successfully prepared on a 316L stainless steel substrate using the JP8000 HVOF system with the spraying parameters obtained from the simulation. The surface and cross-sectional morphology, tissue phase, and microhardness of Ni-CeO2 composite coatings were investigated by SEM, XRD, and microhardness tester. The composite coating was further analyzed for wear resistance and corrosion resistance. The results show that powder particles of different particle sizes have different degrees of deflection during the flight. Small size particles are far away from the center axis of the flame flow and poorly heated, while oversized particles can collide with the barrel and contaminate the gun. In addition, the temperature and velocity of the powder particles are influenced by the flame flow. When O / F is 3, the temperature and velocity in the center axis of the flame flow reach the maximum. The powder particles are heated by impact under this flame flow and strike the substrate. To enable the powder to reach the substrate at a temperature higher than the nickel deposition temperature while ensuring the powder does not collide with the nozzle, the particle size should be maintained between 20 μm and 80 μm. After adding CeO2, the microhardness, wear resistance, and corrosion resistance of the composite coating improved, and the surface morphology of the composite coating became flatter and more uniform. However, this improvement reaches its limit when the CeO2 content is 1 wt.%, and the coating has the highest hardness and lowest friction coefficient at this moment. Moreover, its friction coefficient reduced by 39.8 % and 22.2 % compared with the substrate and Ni coating, respectively. At this time, the wear resistance of the composite coating is also 62.5 % higher than that of the Ni coating. When the CeO2 content exceeds this value, the coating is not homogeneous owing to the large number of intercalated phases, and the particle dispersion strengthening effect reduces. Therefore, the coating quality cannot improve. The trajectory of powder particles during HVOF and the influence of coating process parameters on flame flow and particle state were investigated. Furthermore, the effect of adding CeO2 to the composite coating was analyzed and the effect of CeO2 content on the quality of the composite coating was investigated. This study provides guidance on the selection of HVOF Ni coating process parameters and contribute to the study of the mechanism and performance of adding rare earth oxides to the coating. |
| Key words: high-velocity oxygen-fuel(HVOF) composite coatings CeO2 numerical simulation abrasion resistance property |
