Mechanical behavior of Cu-W interface systems upon tensile loading from molecular dynamics simulations

Molecular dynamics simulations reveal that compared with Cu, the Cu/W interface with the Kurdjumov-Sachs relationship possesses higher critical strength in the [1 1 (2) over bar](Cu) or [(1) over bar 1 0](Cu) direction and much lower strength in the [1 1 1](Cu) direction, while its ductility is smaller, mainly due to constraints of the interface and W lattice. The evolution of Shockley partial dislocations of Cu/W interface has a strong correlation with the direction of tensile loading, and three edge dislocations appear in the [1 1 1](Cu) direction, while two and one mixed dislocations in the [1 1 (2) over bar](Cu) and [(1) over bar 1 0](Cu) directions, respectively. The obtained results are discussed and compared to provide a deep understanding of the stress-strain behavior and dislocation evolution of the Cu/W interface.