The aim of this study was to investigate the corrosion behavior of NiCrSi, NiCrTi, and NiCrMo coatings which were deposited by the HVOF process in an alkali chloride environment. The corrosion test was conducted at 600 °C for 100 h of exposure in an alkali salt vapor environment. The coating performance was characterized by field emission scanning electron microscopy equipped with electron-dispersive spectroscopy and X-ray diffraction. The results show that NiCr-based coatings can reduce the corrosion rate. NiCrSi coating has higher corrosion resistance compared to NiCrTi and NiCrMo coatings, which have a corrosion rate value of 0.42 mm/year. The addition of Si results in the dispersion of SiO₂ particles beneath the coating surface and the formation of SiO₂ layers on the coating surface, which causes a decrease in the growth rate of Cr₂O₃, resulting in a thin and continuous protective oxide formation. Meanwhile, TiO₂ dispersed in the NiCrTi coating could not act as a selective oxidation of the oxide scale. In addition, Mo dispersion plays a role in the formation of volatile MoO₃ and MoCl₄, resulting in the formation of spinel NiCr₂O₄.

本研究的目的是研究在碱金属氯化物环境中采用 HVOF 工艺沉积的 NiCrSi、NiCrTi 和 NiCrMo 涂层的腐蚀行为。腐蚀试验在600℃、碱盐蒸气环境中暴露100h进行。涂层性能通过配备电子色散光谱和X射线衍射的场发射扫描电子显微镜进行表征。结果表明，NiCr基涂层可以降低腐蚀速率。与腐蚀速率值为0.42毫米/年的NiCrTi和NiCrMo涂层相比，NiCrSi涂层具有更高的耐腐蚀性。Si的添加导致SiO ₂颗粒分散在镀层表面下方，并在镀层表面形成SiO _{2层，导致Cr 2} O ₃的生长速率降低，形成薄而连续的保护性氧化物形成。同时，分散在NiCrTi镀层中的TiO _{2不能对氧化皮起到选择性氧化作用。}此外，Mo分散体在挥发性MoO ₃和MoCl _{4的形成中发挥作用，从而导致尖晶石NiCr 2} O ₄的形成。