A first-principles study on the doping stability and micromechanical properties of alloying atoms in aluminum matrix

Abstract

In this paper, the effects of a series of alloying atoms on the stability and micromechanical properties of aluminum alloy was studied by the first-principles calculations of density functional theory. Each alloy atom doping system is optimized, and the difficulty of alloying atom doping in the aluminum matrix is judged by the doping energy of the alloy atom doping system. On the basis of the stable structure, the fracture energy and theoretical tensile stress of different alloy atomic systems were calculated. The fracture energy and theoretical stress of the doped system were used to evaluate the micromechanical properties of the alloy doped system. The density of states, layout analysis, charge density and differential charge density are well explained for the solid solution strengthening effect of alloying atoms in aluminum matrix. The research results show that K, Na, Y, Tl and other alloy atoms are not easily doped into the aluminum alloy, and the alloy atoms Sc, Cu, B, Zr, Ni, Ti, Nb, V, Cr, Mn, Mo, and W have a strengthening effect. The theoretical study on the solid solution and strengthening effect of different alloy atoms in aluminum matrix can provide theoretical guidance for further selection of appropriate alloy elements. The theoretical study of alloy atoms in aluminum matrix reveals the essence of solution strengthening effect, and will greatly shorten the period of developing new aluminum alloys.