Microstructure and shear strength of a Cu–Ta interface

Molecular dynamics simulations with an embedded atom potential are used to study the energy and microstructure of several low-index copper–tantalum interfaces. Existing embedded atom method (EAM) potentials for copper and tantalum are used with minor modifications, and the potential describing copper–tantalum interaction is found by parameter optimization. Shear strength of these systems is studied with a constant shear strain rate loading simulation. Yield stress of the system is correlated with the energy of the interface. A large positive correlation is found indicating that interfaces with small energy are weak. Reasons and consequences are discussed.