TY - JOUR

T1 - Corrosion behaviour of magnesium alloys with RE additions in sodium chloride solutions

AU - Morales, E. D.

AU - Ghali, E.

AU - Hort, Norbert

AU - Dietzel, W.

AU - Kainer, K. U.

N1 - Conference code: 2

PY - 2003/3/15

Y1 - 2003/3/15

N2 - The corrosion performance of new creep resistant magnesium-rare earth alloys was studied and related to its microstructure and chemical composition. The commercial alloy MEZ™ was used as reference. The alloys were produced by the Squeeze Cast Technique. Corrosion was studied in two media: ASTM Water (mild medium) and in 3.5% NaCl at pH 11 (strong medium) by measuring electrochemical polarization curves and by examination of the pitting morphology. Mg-Al-RE alloys had the best corrosion resistance in mild medium. In the aggressive medium, the reference alloy with high RE-content was the best, followed by the Mg-Al-RE alloys. High ratios of Fe/Mn were found detrimental for the corrosion properties of the alloys, especially in strong media. The microstructure played an important role: the eutectic phases of the alloys were cathodic to the matrix and acted as barriers against the propagation of the pitting corrosion. Filiform corrosion was observed additionally in the Mg-Al-RE alloys.

AB - The corrosion performance of new creep resistant magnesium-rare earth alloys was studied and related to its microstructure and chemical composition. The commercial alloy MEZ™ was used as reference. The alloys were produced by the Squeeze Cast Technique. Corrosion was studied in two media: ASTM Water (mild medium) and in 3.5% NaCl at pH 11 (strong medium) by measuring electrochemical polarization curves and by examination of the pitting morphology. Mg-Al-RE alloys had the best corrosion resistance in mild medium. In the aggressive medium, the reference alloy with high RE-content was the best, followed by the Mg-Al-RE alloys. High ratios of Fe/Mn were found detrimental for the corrosion properties of the alloys, especially in strong media. The microstructure played an important role: the eutectic phases of the alloys were cathodic to the matrix and acted as barriers against the propagation of the pitting corrosion. Filiform corrosion was observed additionally in the Mg-Al-RE alloys.

KW - 3.5% NaCl

KW - ASTM Water

KW - Filiform corrosion

KW - Magnesium

KW - Microstructures

KW - Pitting corrosion

KW - Polarization curves

KW - Rare earths

KW - Squeeze cast

KW - Engineering

UR - http://www.scopus.com/inward/record.url?scp=19244372196&partnerID=8YFLogxK

U2 - 10.4028/www.scientific.net/msf.419-422.867

DO - 10.4028/www.scientific.net/msf.419-422.867

M3 - Conference article in journal

AN - SCOPUS:19244372196

VL - 419-422

SP - 867

EP - 872

JO - Materials Science Forum

JF - Materials Science Forum

SN - 0255-5476

IS - II

T2 - Second Osaka International Conference on Platform Science and Technology for Advanced Magnesium Alloys 2003

Y2 - 26 January 2003 through 30 January 2003

ER -