Effect of laser shock peening on corrosion behaviors of ultra-high strength Al-Zn-Mg-Cu alloys prepared by spray forming and ingot metallurgy. (15th August 2022)

• Record Type: Journal Article
• Authors: Wang, Weiyi; Pan, Qinglin; Wang, Xiangdong; Ye, Ji; Huang, Zhiqi; Xiang, Shengqian; Liu, Bing
• Is Part Of: Corrosion science. Volume 205(2022)
• Publication Date: 2022-08-15
• Subjects: Ultra-high strength Al-Zn-Mg-Cu alloys -- Pitting corrosion -- Intergranular corrosion -- Cyclic polarization -- Electrochemical impedance spectroscopy -- Microstructural evolution; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110458
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: In the present work, laser shock peening was applied to the ultra-high strength Al-Zn-Mg-Cu alloys prepared by ingot metallurgy and spray forming. The microstructural evolution, pitting corrosion, intergranular corrosion resistance and electrochemical analysis were systematically investigated. The depth and number of corrosion pits caused by Al matrix, Al7 Cu2 Fe and Al2 CuMg particles can be successfully reduced by laser shock peening. The depth of intergranular corrosion and the width of intergranular cracks also decreased. Cyclic polarization and electrochemical impedance spectroscopy tests also indicated the improved corrosion resistance caused by laser shock peening. The relationship between microstructural evolution and corrosion resistance was studied. Highlights: Corrosion resistance of ultra-high strength Al-Zn-Mg-Cu alloys is promoted by laser shock peening. Al2 CuMg and Al7 Cu2 Fe phases act as preferred sites for pitting corrosion. Al2 CuMg phase can cause deeper corrosion pits than Al7 Cu2 Fe phase. Depth of pitting and intergranular corrosion are ameliorated by laser shock peening. Residual compressive stress, line and surface defects is conducive to corrosion resistance.