Zaki Ahmad, Abdul Aleem B. Aleem, Mohammad Abbas
DOI: 10.4236/msa.2011.24031   PDF    HTML     5,748 Downloads   9,898 Views   Citations

Abstract

Scandium addition significantly alters the corrosion resistance and mechanical strength of Al-3 Mg alloys. The addition of 0.3% - 0.4% scandium with 0.14% zirconium has a beneficial effect on the corrosion resistance of the alloy under smoothly stirred condition. Addition of 0.3% Sc significantly suppresses corrosion under dynamic flow conditions. It also creates an optimal strengthening effect on the alloys. The corrosion resistance is attributed to the strong passive layer of Sc₂O₃ formed on the ultrafine coherent precipitates of Al₃Sc. A strong evidence of the pinning of grain bounda-ries by coherent nano Al3Sc precipitates is responsible for the strengthening effect.

Keywords

Corrosion, Polarization, Passive, Pitting, Strengthening Effect, Pinning, Grain Boundaries, Precipitates, Films, Passive Layers

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Conflicts of Interest

The authors declare no conflicts of interest.

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