铝稀土涂层制备及其防腐性能试验研究

Preparation of Al rare earth coating and experimental study on its corrosion resistance

制备铝粉和镧粉不同配比的铝稀土涂层,以不同厚度涂于Q235碳钢表面。采用盐雾试验、埋片试验、浸泡试验及电化学试验,确定铝稀土涂层中各成分的最佳配比及适宜厚度,分析埋片的腐蚀机理,研究铝稀土涂层的防腐过程和机理。试验结果表明:铝稀土涂层在镧粉质量分数为0.7%、铝粉质量分数为34.3%、涂层厚度为0.2 mm时,防腐性能最佳。在沿海土壤环境中,Q235碳钢的腐蚀速率随p H、含水率、含盐量的增大而增大。在海水环境中,铝稀土涂层对Q235碳钢起到了物理隔离作用,且在不同环境下,铝稀土涂层均表现出优异的防腐性能。

Al rare earth coating is prepared by varying ratios of aluminum and lanthanum powder and is applied on the surface of Q235 carbon steel samples in different thickness. Salt spray experiment,embed experiment,soaking experiment and electrochemical experiment were carried out to determine the optimal blending ratio of each component and the proper thickness of Al rare earth coating,analyze the corrosion mechanism of the embed,and study the corrosion prevention process and its mechanism of the Al rare earth coating. The results show that the best corrosion prevention performance occurs when the lanthanum powder mass fraction is 0. 7 %,the aluminum powder mass fraction is34. 3 % and the coating thickness is 0. 2 mm. In the offshore soils,the corrosion rate of Q235 carbon steel increases with the p H,water content rate and salt content. In the seawater,Al rare earth coating physically isolates the Q235 carbon steel. No matter what the circumstance is,the Al rare earth coating has outstanding corrosion prevention performance.