Corrosion resistance of Mg-Al-Zn magnesium alloy concrete formwork in Portland cement paste
By Wang, Danqian; Wang, Ye; Wang, Jinxing; Ma, Kai; Dai, Chaoneng; Wang, Jingfeng; Pan, Fusheng
Published in Construction and Building Materials
2022
Abstract
Corrosion resistance of Mg-Al-Zn magnesium alloy (AZ41) embedded in PC paste was investigated with 6061 aluminium alloy (AA6061) as s control. Electrochemical methods were adopted to assess the corrosion resistance of AZ41 and AA6061 and surface characterizations were carried out to obtain the morphology and composition of oxide films formed. Results show that the corrosion resistance of AZ41 is obviously higher than that of AA6061 in PC paste due to the formation of a much more compact and thinner oxide film on AZ41. The oxide films on AZ41 and AA6061 are both n-type semiconductors. The oxide film formed on AZ41 mainly consists of uniform Mg(OH)2 layer and Mg(OH)2 + Ca2SiO5 particles on AZ41 substrate as well as manganese oxide on Al-Mn second phase, while the oxide film formed on AA6061 is mainly composed of AlOOH, Ca2Al2O4 and Ca2SiO5.