Linear Potentiodynamic Characterization of ECAPed Biocompatible AZ91 Magnesium Alloy

Abstract:

Mechanical properties and corrosion resistance of Mg alloys basically depend on their chemical composition. Both the mentioned can be influenced by mechanical or heat treatment. In this work was studied the effect of production technology and resulting microstructure on the corrosion resistance of AZ91 alloy. Corrosion resistance of the alloy (AZ91) was analyzed for material after casting and after treatment by ECAP. Result of ECAP treatment is fine grained microstructure of AZ91 alloy and uniform distributed of present intermetallic phases. Corrosion resistance of the experimental material was analyzed in 0.1 molar solution of NaCl through potentiodynamic tests. The ultra-fine grained microstructure after ECAP results in movement of thermodynamic curves to more positive values of corrosion potential (E_corr). From thermodynamic point of view, this means, that AZ91 alloy after ECAP has slightly higher corrosion resistance, as AZ91 alloy after casting; however the improvement of corrosion resistance is only minor due to the high reactivity of the magnesium in the corrosion environment.

• Periodical: Materials Science Forum (Volume 891)
• Pages: 404-408
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.891.404
• Online since: March 2017
• Authors: Kamil Borko*, Stanislava Fintová, Branislav Hadzima
• Keywords: AZ91 Magnesium Alloy, Equal Channel Angular Pressing (ECAP), Potentiodynamic Test

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