Dislocation mechanism of void growth at twin boundary of nanotwinned nickel based on molecular dynamics simulation

• Dislocation mechanism of void growth at TB of nanotwinned nickel is investigated.
• Deformation of the nanotwinned nickel is dominated by leading and trailing partials.
• Growth of void at TB is caused by successive emission and escape of these partials.

Molecular dynamics simulation was performed to investigate dislocation mechanism of void growth at twin boundary (TB) of nanotwinned nickel. Simulation results show that the deformation of nanotwinned nickel containing a void at TB is dominated by the slip involving both leading and trailing partials, where the trailing partials are the dissociation products of stair-rod dislocations formed by the leading partials. The growth of a void at TB is attributed to the successive emission of the leading partials followed by trailing partials as well as the escape of these partial dislocations from the void surface.