Aqueous corrosion behavior of creep resistant Mg-Al-Ba-Ca alloys in sodium chloride solutions
AbstractThe corrosion performance of creep resistant HPDC and PDC (permanent mould direct chill casting) Mg-Al-Ba-Ca alloys was investigated in three aqueous sodium chloride solutions. These ABaX materials were compared to HPDC AZ91D and PDC AZ91D and creep resistant HPDC AE42. Electrochemical measurements and SEM/EDX analysis of original material and corroded cross-sections were conducted, in order to draw a correlation between corrosion behavior and microstructure. The major factor determining the corrosion in ABaX alloys was found to be the shape and distribution of second phases, prompting the formation of microgalvanic corrosion instead of serving as a barrier.