Corrosion Science and Technology

The Corrosion Science Society of Korea (한국부식방식학회)
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A Comparison of Corrosion Performance of Zirconium Grain Refined MEZ and AZ91 Alloys

  • Song, Guangling (CRC for Cast Metals Manufacturing (CAST) Department of Mining, Minerals and Materials Engineering, The University of Queensland) ;
  • StJohn, David (CRC for Cast Metals Manufacturing (CAST) Department of Mining, Minerals and Materials Engineering, The University of Queensland)
  • Published : 2003.02.01
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Abstract

In this study, sand cast AZ91E and zirconium grain refined MEZ are representative of two typical groups of magnesium alloys: those containing aluminium and those containing no aluminium but with zirconium as a grain refiner. The corrosion performance of these two alloys was evaluated and compared in 5%wt NaCI solution through measurements of weight loss and polarisation curves and examination of microstructure. Corrosion damage of AZ91E was deeper and more localised than that of MEZ, while MEZ had a lower rate of cathodic hydrogen evolution and a higher rate of anodic dissolution than AZ91E. These differences in behaviour can be related to the differences in microstructure and chemical composition between the two alloys.

Keywords

Acknowledgement

Supported by : University of Queensland

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