Investigation on the interface properties of Be-Al alloys via first-principles calculation

Abstract

In this paper, the Be/Al pure interface is constructed using First-principles calculation. Among the six interface structures, the interface adhesion work calculation results show that the Be (001)/Al (100) interface has the largest adhesion work (2.48 J/m2), which proves that the Be (001)/Al (100) interface is the most stable interface structure. Also, the Be (001)/Al (100) composite interface structure doping elements of Ni, Ag, Co and Ge was constructed. The results of segregation heat and interface adhesion work calculation showed that the addition of Ni, Ag and Co was beneficial to the improvement of the Be (001)/Al (100) interface strength. The doping effect of Ag and Co is similar, followed by Ni, and the doping of Ge leads to the degradation of interface properties. The calculation results of the partial density of states (PDOS) and the charge density difference show that in the pure Be (001)/Al (100) interface structure, a metallic bond is formed between Be and Al atoms near the interface. With the introduction of doping elements, the charge between Be and Al atoms is redistributed. A stronger new metal bond of Be-X or Al-X (X=Ni, Ag, Co) is formed, but the doping of Ge elements forms a weaker Be-Ge metal bond, which is not conducive to the performance improvement of Be-Al alloys.