Structural, elastic and electronic properties of typical NdMgT 4 (T = Co, Ni, Cu) alloys from ab initio calculation

Abstract The crystal structure, elastic and magnetic properties of important ternary Mg-based alloys NdMgT 4 (T = Co, Ni, Cu) have been studied using reliable ab initio calculations. Both cohesive energy and charge density difference suggest that three alloys have good structural stability with the order: NdMgCo 4  > NdMgNi 4  > NdMgCu 4 . It shows that NdMgCo 4 alloy has magnetic moments with the Co atoms being the main contribution, which is also in agreement with the calculated electronic structures. We find that NdMgT 4 (T = Co, Ni, Cu) alloys are all ductile materials with bulk-to-shear modulus (B/G) values higher than 1.75. The trends of calculated values for the shear moduli C s and C 44 are consistent with that of shear modulus G and young's modulus E, proving that NdMgT 4 (T = Co, Ni, Cu) alloys exhibit good plasticity with the trend: NdMgNi 4  > NdMgCu 4  > NdMgCo 4 . These calculated results give the basis guidance for the design of rare earth-magnesium-transition metal (R-Mg-T) alloys with improved mechanical properties.