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New anodizing process for magnesium alloys

  • Luo Sheng-lian 
  • Dai Lei 
  • Zhou Hai-hui 
  • Chai Li-yuan 
  • Kuang Ya-fei Email author
Article

Abstract

Compact anodic films with high hardness and good corrosion resistance on magnesium alloys were prepared by a new constant voltage and arc-free anodizing process. The effects of anodizing parameters such as applied voltage and electrolyte temperature on the peak current density and the thickness of films were investigated. In addition, the morphologies and corrosion resistance of films were investigated by scanning electron microscopy and potentiodynamic polarization, respectively. The results show that the higher the applied voltage, the higher the peak intense sparking which may deteriorate the properties of the anodic films and bring about unsafety. The new anodizing process can be applied in a wide range of temperature. The new anodic films have numbers of pores with the diameter of 0.5–5.0 µm which do not transverse the entire film.

Key words

magnesium alloys anodizing film arc-free corrosion resistance 

CLC number

TG174. 451 

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Copyright information

© Central South University 2006

Authors and Affiliations

  • Luo Sheng-lian 
    • 1
    • 2
  • Dai Lei 
    • 2
  • Zhou Hai-hui 
    • 2
  • Chai Li-yuan 
    • 1
  • Kuang Ya-fei 
    • 2
    Email author
  1. 1.School of Metallurgical Science and EngineeringCentral South UniversityChangshaChina
  2. 2.School of Chemistry and Chemical EngineeringHunan UniversityChangshaChina

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