锆盐封孔对建筑铝合金阳极氧化膜耐蚀性能的影响

Effect of Zirconium Salt Sealing on Corrosion Resistance of Anodic Ox‐ide Film on Aluminium Alloy Used in Construction

为了改善建筑常用6463铝合金的耐蚀性能,在其表面制备阳极氧化膜,然后采用氟锆酸钾溶液对阳极氧化膜进行封孔处理。研究了锆盐封孔对阳极氧化膜的微观形貌、表面成分和耐蚀性能的影响,并与沸水封孔和镍盐封孔进行了对比。结果表明:锆盐封孔对阳极氧化膜微观形貌的改善效果明显好于沸水封孔,阳极氧化膜中引入Zr元素,质量分数约为19.35%。锆盐封孔阳极氧化膜表面较平整致密,粗糙度为0.296μm,其耐蚀性能与镍盐封孔阳极氧化膜接近,明显好于沸水封孔阳极氧化膜。锆盐封孔具有双重封孔效果,可以有效抑制腐蚀过程,使阳极氧化膜的腐蚀电位正移约103 mV,腐蚀电流密度降低了超过一个数量级,腐蚀失重降低到0.48 g/m^(2)。

In order to improve the corrosion resistance of 6463 aluminum alloy which is commonly used in construction,an anodic oxide film was prepared on its surface,and then the anodic oxide film was sealed with potassium fluorozirconate solution.The effects of zirconium salt sealing on the microstructure,surface composition and corrosion resistance of anodic oxide film were studied,and compared with boiling water sealing and nickel salt sealing.The results showed that zirconium salt sealing has a better effect on the improvement of the microstructure of the anodic oxide film than that of boiling water sealing,and Zr element was introduced into the anodic oxide film,its mass fraction was about 19.35%.The surface of zirconium salt sealed anodic oxide film is flat and compact,and the roughness is 0.296μm.Its corrosion resistance is close to that of nickel salt sealed anodic oxide film,which is obviously better than that of boiling water sealed anodic oxide film.Zirconium salt sealing has double sealing effect,which can effectively inhibit the corrosion process,move the corrosion potential of anodic oxide film forward by about 103 mV,reduce the corrosion current density by more than one order of magnitude,and reduce the corrosion weight loss to 0.48 g/m^(2).