Ab-Initio Studies of the Micromechanics and Interfacial Behavior of Al₃Y|fcc-Al

Abstract

In this paper, an Ab-initio study was employed to study the properties of interfaces of Al3Y|Al. The interface strength, shear strength, structural stability, electronic density, bonding characteristics, stacking fault energy, and plasticity were all investigated. The interface with the stacking style of ABab or CBAcba has the greatest interface strength. The Al3Y(111)|Al(111) interface has the highest tensile stress of 13.39 GPa for rigid stretching; and 9.39 GPa for relaxation stretching. In the stretching process, the Al3Y(111)|Al(111) interface is prone to break on the Al3Y side. However, the Al3Y(010)|Al(010) and Al3Y(110)|Al(110) interface systems tend to fracture at the interface and Al side, respectively. Moreover, the differential charge density, electron localization function, and partial density of states (PDOS) demonstrate the newly formed chemical bonds at the interface, and the chemical bonds were formed by s-p or s-p-d hybrid orbitals. According to the Rice ratio and shear stress, these interfaces were found to be plastic and the Al3Y(111)|Al(111) interface has the best plasticity. This is significant because the formed interfaces are all advanced structure materials, which can be potentially used in automobile and aeronautical fields, even in some special industries.

Keywords

• interfacial strength
• unstable stacking fault energy
• plasticity
• interfacial energy