Density functional theory study of phase stability and electronic properties for L12 X3Ru and XRu3 alloys

Abstract This study employs first-principles density functional theory (DFT) to investigate the structural, mechanical, electronic, and phonon properties of L1 2 -phase X 3 Ru and XRu 3 alloys (X = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn). Our findings indicate that Sc 3 Ru, Ti 3 Ru, V 3 Ru, Mn 3 Ru, Zn 3 Ru as well as Ru 3 Ti, Ru 3 V, and Ru 3 Mn alloys are thermodynamically stable. All the X 3 Ru and XRu 3 alloys exhibit mechanical stability, except for Ti 3 Ru and Fe 3 Ru. The density of states results reveal metallic behavior across all the X 3 Ru and XRu 3 alloys, while charge density plots indicate metallic bonding between X and Ru, consistent with the electronic properties. Phonon dispersion curves confirm the dynamic stability in TiRu 3 , VRu 3 , CrRu 3 , MnRu 3 , FeRu 3 , CoRu 3 , CuRu 3 , ZnRu 3 as well as in Cr 3 Ru, Cu 3 Ru and Co 3 Ru alloys. Notably, TiRu 3 , VRu 3 , MnRu 3 also demonstrate thermodynamic and mechanical stability, along with higher melting temperatures compared to the widely used Ni 3 Al alloy. These findings lay a theoretical foundation for further experimental investigations of X 3 Ru and XRu 3 alloys, which may be promising candidates for high-temperature structural applications. Graphical abstract