|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Magnesium Technology 2017
||I-31: First-principles Model of Alloy-dependent Magnesium Corrosion
||Krista Limmer, Joseph Labukas, Michael Garvey, Santanu Chaudhuri, Jan Andzelm
|On-Site Speaker (Planned)
The rapid corrosion of magnesium is one of the primary limitations for using magnesium in lightweight structural applications. Recent experimental work has suggested that As poisons the cathodic reaction on magnesium, preventing hydrogen recombination and evolution. In this study the mechanism of cathodic poisoning from metalloid alloying was investigated from first principles using density functional theory. The effect of metalloids was investigated by examining the cathodic reaction on multiple surface configurations within the alloy system including: 1) dilute metalloid concentrations in magnesium solid solution, 2) second phase precipitates, and 3) metalloid adatoms. The effect on corrosion was determined by considering the kinetic barriers associated with hydrogen diffusion, recombination, and evolution. This mechanistic understanding of how metalloids contribute to the poisoning of magnesium corrosion may be used to develop magnesium alloy systems with reduced corrosion kinetics.