Study of the Corrosion and Surface Film Growth on AZ63 Magnesium Alloy in MgSO4 Solution. Issue 6 (1st January 2017)

• Record Type: Journal Article
• Authors: Yang, Qiaoling; Chen, Lin; Xu, Jing; Gong, Youlai; Deng, Ling; Chen, Changguo
• Is Part Of: Journal of the Electrochemical Society. Volume 164:Issue 6(2017)
• Page Start: C324
• Page End: C329
• Publication Date: 2017-01-01
• Subjects: AZ63 magnesium alloy -- corrosion film -- growth model -- Mg/MnO2 battery -- voltage delay; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.1651706jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Comprehending the mechanism of corrosion film growth on the anode in electrolytes is a foundation in the tailoring of a desirable delayed action in magnesium–manganese dioxide (Mg/MnO2 ) primary batteries. The formation and growth evolution of the corrosion film on AZ63 magnesium alloys in 2 mol L −1 MgSO4 aqueous solution was investigated by scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Results indicate that corrosion preferentially occurred on the α phase adjacent to the β phase of the alloy before spreading to the area away from the β phase. The β phase acted as a micro cathode that accelerates the corrosion dissolution. The film consisted of a base film and mosaic particles with amorphous mixed compositions of MgO, Mg(OH)2, (MgCO3 )4 ·Mg(OH)2 ·4H2 O, and Mg(OH)2 ·2MgSO4 . The formation and growth of the film on the AZ63 magnesium can be divided into three stages: film formation, film composition transformation, and film structure breakdown. A film growth model was also proposed for interpreting the corrosion evolution of the AZ63 alloy.