HVOF喷涂用于提高锅炉换热面耐磨损耐腐蚀性能综述

火力发电是我国的主要发电方式，在燃用煤、生物质等固体燃料时会面临锅炉换热面的冲蚀磨损或腐蚀问题，导致管道失效停炉，严重影响了电厂的安全稳定运行。超声速火焰（HVOF）喷涂作为热喷涂工艺的一种，可以通过在换热管道表面添加防护涂层来缓解磨损或腐蚀问题。因其制备的涂层具有与基体结合强度高、孔隙率低等优异的特点，在锅炉换热面的耐磨损耐腐蚀方面研究及应用前景广阔。综述了HVOF喷涂的发展、工艺流程以及涂层的特性，并重点总结了用于提升锅炉换热面耐磨损耐腐蚀性能的HVOF涂层材料，以及不同材料应用时需要考虑的环境因素。最后从工艺优化、材料进步以及实验方法创新三个方面对HVOF工艺在锅炉换热面上的应用做出展望。

Summary of improving erosion and corrosion resistance of heat exchange surfaces in boilers through HVOF technology

Thermal power generation is main power generation method in China. When burning solid fuels such as coal and biomass, it will face erosion and wear or corrosion problems on the heating exchange surface of the boiler, causing pipeline failure and shutdown of the boiler, seriously affecting the safe and stable operation of the power plant. As one kind of thermal spraying technology, high velocity oxy-fuel (HVOF) spraying can alleviate the erosion and corrosion problem by adding protective coatings on the surface of the heat exchange tubes. Coatings prepared by HVOF spraying have good applicability under erosion and corrosion environment in boilers since their excellent characteristics such as high bonding strength and low porosity. The development of HVOF technology, the spraying process and coating characteristics were reviewed in this article, and common anti-erosion/anti-corrosion coatings and environmental factors needed to be considered when applying different coating materials were summarized. According to various literatures, the adopted anti-erosion HVOF coatings are mainly NiCr alloys, stellite alloys, WC-Co, Cr₃C₂-NiCr and other metal or cermet coatings. Comprehensive consideration of fly ash composition, erosion angle, and erosion temperature is needed when selecting coating materials in boilers. The adopted anti-corrosion coating materials are mainly Ni-based or Fe-based alloys, of which Ni-based materials are particularly dominant. The tube wall temperature and corrosive substances are the main environmental factors affecting the application of anti-corrosion coatings. Different from various options in literatures, coating materials used in actual boilers are quite simple, mainly Cr₃C₂-NiCr and Inconel 625 for erosion and corrosion protection respectively. Moreover, HVOF is not a common coating preparation technology mainly due to its high cost. To bridge the gap between researches and practical applications of HVOF coatings, spraying process optimization, progress in coating materials and experimental method innovation is prospected in this article.