Influence of alloyed magnesium on the microstructure and long-term corrosion behavior of hot-dip Al–Zn–Si coating in NaCl solution. (March 2016)

• Record Type: Journal Article
• Authors: Liu, Wei; Li, Mou-Cheng; Luo, Qun; Fan, Hong-Qiang; Zhang, Jie-Yu; Lu, Hu-Sheng; Chou, Kuo-Chih; Wang, Xun-Li; Li, Qian
• Is Part Of: Corrosion science. Volume 104(2016)
• Page Start: 217
• Page End: 226
• Publication Date: 2016-03
• Subjects: A. Metal coatings -- A. Magnesium -- B. Weight loss -- B. EIS; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.12.014
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: Equilateral triangle Mg2 Si phases appear on the surface of Al–Zn–Si– x Mg coatings. Mg-rich phase can obviously improve the corrosion resistance of Al–Zn–Si– x Mg coatings. Zn–Al LDH more easily precipitates on the Al–Zn–Si– x Mg coatings with Mg 2+ . Mg2 Si has better anti-corrosion effects than MgZn2. De-alloying stage of Mg2 Si contributes to prolong the cathodic protection effect. Abstract: The effects of alloyed magnesium on the corrosion behavior of hot-dip Al–Zn–Si– x Mg ( x = 0, 1.25, 3 and 4 wt.%) coatings were investigated by analysis of the phase composition, long-term immersion test and electrochemical measurements. Mg2 Si phase appeared in the Al–Zn–Si–1.25Mg and Al–Zn–Si–3Mg coatings but only MgZn2 phase existed on the surface of Al–Zn–Si–4Mg coating. The alloyed magnesium improves the corrosion resistance of the Mg-containing coatings and the Al–Zn–Si–3Mg coating shows the highest protective properties in the investigation.