Screening corrosion-resistant binary magnesium alloys through high-throughput computations

Magnesium (Mg) alloys have shown great potential as both structural and biomedical materials due to their high strength-to-weight ratio and good biocompatibility. However, poor corrosion resistance limits their further application, while alloying is believed to be one of the most effective strategies to develop corrosion-resistant Mg alloys. Recently, high-throughput computational method has become a useful tool to screen promising materials for various applications. In this work, we first collected 27919 (including repeated) Mg intermetallics structures from online databases, from which 332 stable candidates were selected. Then, the equilibrium potential based on Nernst equation were calculated and 50 Mg intermetallics with smallest equilibrium potential difference from that of Mg matrix and hence the lowest thermodynamic driving force of galvanic corrosion were reserved. From the idea of small cathodic exchange current density and thermodynamic driving force of galvanic corrosion, several intermetallics were selected to be the promising phases for corrosion-resistant binary alloys. Our work provides a high-throughput screening strategy for corrosion-resistant alloy design, which can also be extended to screen ternary intermetallics or other alloy systems.