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Improving the corrosion properties of magnesium AZ31 alloy GTA weld metal using microarc oxidation process

  • M. Siva Prasad
  • M. Ashfaq
  • N. Kishore Babu
  • A. Sreekanth
  • K. Sivaprasad
  • V. Muthupandi
Article

Abstract

In this work, the morphology, phase composition, and corrosion properties of microarc oxidized (MAO) gas tungsten arc (GTA) weldments of AZ31 alloy were investigated. Autogenous gas tungsten arc welds were made as full penetration bead-on-plate welding under the alternating-current mode. A uniform oxide layer was developed on the surface of the specimens with MAO treatment in silicate-based alkaline electrolytes for different oxidation times. The corrosion behavior of the samples was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy. The oxide film improved the corrosion resistance substantially compared to the uncoated specimens. The sample coated for 10 min exhibited better corrosion properties. The corrosion resistance of the coatings was concluded to strongly depend on the morphology, whereas the phase composition and thickness were concluded to only slightly affect the corrosion resistance.

Keywords

magnesium alloys weldments microarc oxidation corrosion resistance 

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Notes

Acknowledgments

The authors would like to acknowledge the Department of Metallurgical and Materials Engineering, National Institute of Technology, Tiruchirapalli for providing the funds and facilities to conduct this research work.

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Copyright information

© University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • M. Siva Prasad
    • 1
    • 2
  • M. Ashfaq
    • 3
  • N. Kishore Babu
    • 4
  • A. Sreekanth
    • 5
  • K. Sivaprasad
    • 2
  • V. Muthupandi
    • 2
  1. 1.Department of Advanced Materials EngineeringDong-Eui UniversityBusanSouth Korea
  2. 2.Advanced Materials Processing Laboratory, Department of Metallurgical and Materials EngineeringNational Institute of TechnologyTiruchirapalliIndia
  3. 3.FARCAMT, Advanced Manufacturing InstituteKing Saud UniversityRiyadhSaudi Arabia
  4. 4.Laboratory for Advanced Materials ProcessingEmpa, Swiss Federal Laboratories for Materials Science and TechnologyThunSwitzerland
  5. 5.Department of ChemistryNational Institute of TechnologyTiruchirappalliIndia

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