Influence of Gd on the corrosion behavior of AM50 and AZ91D magnesium alloys
2012
Arrabal, R. | Pardo, A. | Merino, M. C. | Paucar, K. | Mohedano, M. | Casajús, P. | Garcés, Gerardo
The corrosion behavior of AM50 and AZ91D Mg alloys containing 0.2 wt% to 1.0 wt% Gd was evaluated in 3.5 wt% sodium chloride (NaCl) solution using electrochemical, gravimetric, and hydrogen evolution methods. Corrosion products were examined using scanning electron microscopy and low-angle x-ray diffraction. Gd addition reduced the volume fraction of β-Mg 17Al 12 phase because of the precipitation of Al 2Gd and Al-Mn-Gd intermetallic compounds, which revealed lower surface potential than Al-Mn inclusions in the unmodified alloys. The corrosion rate of AM50 and AZ91D alloys decreased with the addition of Gd by 85% to 93%. This effect was associated mainly with the decreased rate of cathodic reaction kinetics because of the suppression of microgalvanic corrosion between primary and secondary phases. © 2012, NACE International.
显示更多 [+] 显示较少 [-]The authors are grateful to the MCYT (Spain, Project MAT 2009-09845-C02-01), the Community of Madrid (Spain, S2009MAT-1585), and the MANOEQ of Departamento de Metalurgia Física of CENIM (CSIC) for supplying the test materials. R. Arrabal is grateful to the MICINN (Spain) for financial support via the Ramon y Cajal Programme (RYC-2008-02038). K. Paucar is grateful to the Fundación Carolina for funding a grant.
显示更多 [+] 显示较少 [-]Peer Reviewed
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