目的 提高涂层耐腐蚀性能，并研究封孔剂中铝硅溶胶与硅氧烷的比例对封孔性能的影响。方法 以铝硅复合溶胶和甲基三甲氧基硅氧烷（MTMS）为主要原料，通过溶胶-凝胶法制备无机-有机复合封孔剂，并对Cr3C2-NiCr热喷涂涂层进行封孔，探究不同比例的复合封孔剂对涂层耐腐蚀性能的影响。采用X射线衍射（XRD）、热重-差热（TG-DTA）、扫描电子显微镜（SEM）检测研究封孔层物相组成、热稳定性和微观形貌。通过极化曲线和电化学阻抗谱测试研究封孔前后涂层的耐腐蚀性能，并以全浸泡腐蚀试验对其耐腐蚀性能进一步探究。结果 铝硅复合硅氧烷封孔剂的固化温度在120 ℃左右，固化后，涂层表面光滑致密，封孔剂的耐热温度在300 ℃左右。该封孔剂对涂层孔隙具有良好的填充作用。当铝硅复合溶胶和硅氧烷质量比为3︰2时，涂层的耐腐蚀性最好，其自腐蚀电流密度和阻抗分别为8.671×10–6 A/cm2和4593 Ω?cm2，全浸泡腐蚀速率为4.17×10－3 g/(m2?h)。随着封孔剂中MTMS比例增加，固化过程中不断有裂纹产生，导致涂层的耐腐蚀性能不断降低。结论 制备的封孔剂显著提高了涂层的耐腐蚀性能，并且在MTMS质量分数为40%时，其耐腐蚀性能最优。

The work aims to improve the corrosion resistance of the coating and study the effect of the ratio of aluminum silica sol and siloxane in the sealing agent on the sealing performance. Aluminum-silicon composite sol and methyltrimethoxysilane (MTMS) were used as the main raw materials to prepare inorganic-organic mixed sealing agent by sol-gel method, and seal the Cr3C2-NiCr thermal spray coating To explore the effect of different proportions of aluminum silica sol and siloxane in composite sealing agent on the corrosion resistance of the coatings. The phases, thermal stability and microstructure of sealed coatings were analyzed by X-ray diffraction (XRD), thermogravimetry-differential thermal analysis (TG-DTA) and scanning electron microscopy (SEM). The corrosion resistance of the coating before and after sealing was studied by polarization curve and electrochemical impedance spectroscopy. The corrosion performance of the coating was further explored by full immersion corrosion test. The curing temperature of Al-Si composite sol was about 120 ℃, and the surface of the coating was smooth and dense after curing. The heat-resistance temperature of the sealing agent was around 300 ℃. The sealing agent had a good effect on pores of the sprayed coating. When the mass ratio of the Al-Si composite sol and the siloxane was 3:2, the coating had the best corrosion resistance. The self-corrosion current density and impedance were 8.671×10-6 A?cm-2 and 4593 Ω?cm2, respectively and the full immersion corrosion rate of the coating was 4.17×10-3 g/(m2?h). However, with the increase of the proportion of MTMS in the sealing agent, cracks appeared during the curing process, which decreased the corrosion resistance of the coating. Therefore, the prepared sealing agent has improved the corrosion resistance of the coating significantly, and the coating gets the best corrosion resistance at an MTMS content of 40%.