帶冷噴Al/Al2O3涂層的20號碳鋼管道在保溫層下的腐蝕行為帶冷噴Al/Al2O3涂層的20號碳鋼管道在保溫層下的腐蝕行為Corrosion Behavior of 20# Carbon Steel with Cold Sprayed Al-Al2O3 Coatings under Insulation 采用浸泡試驗模擬涂層管道在保溫層下的腐蝕，并通過腐蝕失重法、宏觀腐蝕形貌和顯微結構觀察以及微區成分分析，研究了80℃時，在0.01%（質量分數，下同）NaCl、0.1% NaCl以及1% NaCl溶液中，三種涂層（噴涂粉末分別為100% Al、70% Al+30% Al2O3和50% Al+50% Al2O3）對20號碳鋼管道的防護作用。結果表明：當碳鋼管道表面冷噴Al/Al2O3涂層后，管道具有較好的抗保溫層下腐蝕性能。且當噴涂粉末為純鋁粉時，涂層的耐蝕性最好，加入陶瓷相Al2O3后，涂層的沉積厚度與強度均提高，但腐蝕保護效率存在一定程度的下降。綜合考慮涂層的耐蝕性和強度，噴涂粉末為70% Al+30% Al2O3時所得到涂層最適于工程上使用。 Immersion tests were conducted to simulate the corrosion under insulation (CUI) in 0.01%, 0.1% and 1% NaCl solution at 80℃. Corrosion protection performance of three different coatings (initial spray powder were 100% Al, 70% Al+30% Al2O3 and 50% Al+50% Al2O3 respectively) on 20# carbon steel pipe was analyzed by weight loss, macro-appearance, microstructure and chemical component analysis.The results showed that cold sprayed Al/Al2O3 coating could protect the pipe substance from corrosion under insulation effectively. When Al2O3 was added into spray powder, the deposition efficiency and hardness increased, but the corrosion resistance decreased. Overall, considering both corrosion resistance and strength, the coating sprayed with 70% Al+30% Al2O3was most suitable for using in engineering.
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