Corrosion behavior of AZ31 magnesium alloy with calcium addition. (1st May 2022)

• Record Type: Journal Article
• Authors: Chaudry, Umer Masood; Farooq, Ameeq; Tayyab, Kaab bin; Malik, Abdul; Kamran, Muhammad; Kim, Jung-Gu; Li, Chuan; Hamad, Kotiba; Jun, Tea-Sung
• Is Part Of: Corrosion science. Volume 199(2022)
• Publication Date: 2022-05-01
• Subjects: Magnesium -- AZ31–0.5Ca -- Electron back-scattered diffraction -- Potentiodynamic polarization -- Electrochemical impedance spectroscopy; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2022.110205
• Languages: English
• ISSNs: 0010-938X

Abstract

Abstract: The effect of calcium on microstructure and corrosion characteristics of AZ31 was investigated. Electron probe microanalysis, scanning electron microscopy and electron back-scattered diffraction were employed for microstructural analysis. Corrosion behavior was characterized by open circuit potential, potentiodynamic polarization and electrochemical impedance spectroscopy in NaCl at different pH levels. Microstructural observations confirmed the formation of (Mg, Al)2 Ca in AZ31–0.5Ca. The corrosion rates were 84.21 mpy/ 31.71 mpy and 23.42 mpy/ 9.40 mpy for AZ31 and AZ31–0.5Ca at pH 6 and pH 11, respectively. Improved corrosion resistance was attributed to segregation of aluminum with calcium to form (Mg, Al)2 Ca which reduced β-Mg17 -Al12 area fraction. Graphical Abstract: ga1 Highlights: The effect of Ca on the microstructure and corrosion behavior of AZ31 was studied. Microstructure analysis revealed the presence of intermetallic particles in AZ31-0.5Ca. Ca-added AZ31 showed a remarkable improvement in corrosion resistance.