Atomistic simulations of the tensile strength of a disclinated bicrystalline nanofilm

Abstract

The tensile strength of a metallic bicrystalline nanofilm containing a wedge disclination in the middle of a grain boundary (GB) terminating at the film surfaces was studied via atomistic simulations. The results show that an increase in the disclination power strengthens the film, which is contrary to intuition, if a crack initiates at one end of the terminated GB, whereas it weakens the film if a crack initiates at the disclination core. Both the strengthening and weakening demonstrate a size effect for film thickness in the range 10–20 nm, and are also significantly influenced by the GB misorientation. It is further shown that the strength can be increased to ∼80% of the theoretical strength of a defect-free film by introducing a disclination of moderate power in the GB.

Keywords:

• nanoflim
• disclination
• tensile strength
• atomistic simulation

Acknowledgement

This work is supported by the Agency for Science, Technology and Research, Singapore (Grant No: 032 101 0019).