The light aging performance of nano-SiO2 particle composited polyurea coatings were tested by ultraviolet accelerated aging and surface morphology observations. The corrosion resistance to seawater of the coatings was measured by soaking in a 3.5％ NaC1 solution. Field emission scanning electron microscopy, corrosion potential measurements and electrochemical impedance spectroscopy (EIS) were used to analyze the corrosion resistance of different coatings. The results indicate that the corrosion resistance of aromatic polyurea coatings increases significantly by compositing the nano-SiO2 powder. After the compositing, the corrosion potential improves from -40 mV to 60 mV, the EIS modulus increases approximately one magnitude, the accelerated aging stage delays about 120 h, and the life of the coatings in the 3.5％ NaC1 solution increases by 600 h roughly.%采用紫外光暴露+冷凝的紫外加速老化试验,结合表面形貌观察测试了纳米SiO2粉体复合聚脲涂层的光老化性能,采用3.5%NaCl溶液浸泡试验测试了涂层的耐海水浸泡腐蚀性能,通过场发射扫描电子显微镜、自腐蚀电位和交流阻抗图谱等分析了不同涂层的耐蚀性能.结果表明:纳米SiO2粉体显著提高了芳香族聚脲涂层的耐蚀性能,自腐蚀电位由-40mV升高至60mV,电化学阻抗模值增加了约一个数量级,涂层进入迅速老化阶段的时间延长了约120 h,在3.5%NaCl溶液中的浸泡寿命提高了约600 h.
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