High Temperature Mechanical Behavior of Aluminum- Cu50Zr50Metallic Glass Interface

Abstract

Molecular dynamics (MD) simulations are carried out to determine interface strength between aluminum (metal) and Cu50Zr50 (metallic glass) at temperature of 500 K and at strain rate of 108 s-1. Simulation box of size 100 Å (x) × 110 Å (y) × 50 Å (z) is used for the above studies. At first Al-Cu50Zr50 crystalline interface model is built with the base layer-Al of 50 A and the top layer-Cu50Zr50 of 55 Å along y-direction. Later Cu50Zr50 metallic glass is obtained by quenching at a cooling rate of 4 x 1012 Ks-1. NPT ensemble is used in metallic glass preparation simulation. The interface model is then equilibrated at 300 K for 500 ps to relieve the internal stresses. EAM (Embedded Atom Method) potential is used for modelling the interaction between Al-Cu-Zr atoms. The interface strength of Al-Cu50Zr50 model interface is determined by applying load in the directions normal (mode-I) and parallel (mode-II) to the interface. NVT ensemble is used for the deformation studies. In mode-I for perfect and cracked interface, the interface fractures in the Al-region via necking. Sticking of the Al-atoms to the metallic glass is observed in both the loading conditions. Also, multiple voids are nucleated at the interface.