Twin Rotation Induced Detwinning in Nanotwinned Al Tensioned Perpendicular to Twin Boundary by Atomistic Simulation

Abstract

Nanotwinned Al can be used as interconnects in flexible electronic components due to its excellent strength and toughness, which can be further improved. The key is to fully understand the precise physical nature of detwinning in nanocrystalline metals at extremely small twin boundary spacings. Molecular dynamics simulations were performed to investigate the uniaxial tensile deformation of nanotwinned single-crystal Al at room temperature, with tensile stress applied perpendicular to twin boundaries. Simulation results indicate that detwinning does not occur immediately after yield but rather after twin rotation. Intensive detwinning occurs immediately after yield, and the intensity gradually decreases with strain. Detwinning is observed in all models with twin boundary spacings up to 420.89 Å, with the overall intensity of detwinning decreasing as twin boundary spacing increases. The research results of this article further promote the application and development of nanotwinned Al in the field of micro and nano electronics.

Keywords: Detwinning, Twin rotation, Dislocations, Nanotwinned singlecrystal Al, Atomistic simulation