Density functional theory study of the interfacial properties of Ni/Ni3Si eutectic alloy

order to clarify the heterogeneous nucleation potential of alpha-Ni grains on Ni3Si particles in Ni-Ni3Si eutectic alloy, the work of adhesion (W-ad), fracture toughness (G), interfacial energy (gamma(i)), and electronic structure of the index (001), (110) and (111) Ni/Ni3Si interfaces with two different cohesive manners are investigated using first-principles method based on density functional theory. Results indicate that the center site stacking sequence (OM) is preferable to continue the natural stacking sequence of bulk Ni and Ni3Si. Since OM stacking interfaces have larger W-ad, G and gamma(i) than that of the top site stacking (OT) interfaces. The Ni/Ni3Si (110) interface with OM stacking has the best mechanical properties. Therefore, the formation of this interface can improve the stability, ductility and fracture toughness of Ni-Ni3Si eutectic alloy. The calculated interfacial energy of Ni/Ni3Si (001), (110) and (111) interfaces with OM stacking proves the excellent nucleation potency of Ni3Si particles for alpha-Ni phase from thermodynamic considerations. Besides, the electronic structure and chemical bonding of (110) interface with OM stacking are also discussed. (C) 2014 Elsevier B. V. All rights reserved.