High-throughput screening of the potential alloying elements for high-strength Mg alloys based on solid-solution strengthening

Abstract 49 types of alloy atomic dopants and their effects on the doping stability and micro-mechanical behaviour of magnesium matrix were investigated using density functional theory and high throughput first-principles calculations. Geometry optimization was performed for each doping system, and the ability of atom doping into the magnesium matrix was assessed based on the doping energy and atomic radius. Results show that the transition metal elements have negative or near negative doping energy, especially for the elements with a radius that similar to Mg. The micro-mechanical properties of the doping system were evaluated by computing the fracture energy and theoretical tensile stress. Through a screening on the doping stability and strengthening effect of 49 types of alloy atoms, a set of elements (Re, Os, Ir, Tc and W, etc) are screened out that could strengthen the magnesium matrix with a good doping stability. The high throughput screen results serve as a theoretical guide for the selection of appropriate alloy elements for designing the high-strength magnesium alloys in the regime of solid solution strengthening effects.