Effect of Surface Roughness on Corrosion Resistance of Sol-Gel Coatings on AA2024-T3 Alloy. Issue 14 (2nd October 2015)

• Record Type: Journal Article
• Authors: Zhao, Hao; Yu, Mei; Liu, Jianhua; Li, Songmei; Xue, Bing; Liang, Min
• Is Part Of: Journal of the Electrochemical Society. Volume 162:Issue 14(2015)
• Page Start: C718
• Page End: C724
• Publication Date: 2015-10-02
• Subjects: corrosion resistance -- sol-gel coatings -- surface roughness; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0271514jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The effect of surface roughness on the corrosion resistance of sol-gel coatings on 2024-T3 aluminum alloy was studied. Mechanical abrasion with various grit size papers was used to produce different micro roughness on the alloy, and then the hybrid sol-gel coatings were formed. Scanning electron microscopy (SEM) and surface texture measurements were used to characterize the surface morphology. Pull-off tests were used to measure the adhesive strength of the sol-gel coatings. The corrosion protective performance of the coatings was evaluated by using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The adhesion strength of the sol-gel coatings on substrates with different roughness presented the similar value. The results show that the roughness of the metallic surface has significant influence on the corrosion resistance of sol-gel coating on AA2024 alloys. It indicates that the Al alloy with high roughness reduces the corrosion protection of sol-gel coatings.