The interfacial tensile yield strengths of Cu/Nb layered materials containing
helium bubbles are investigated via molecular dynamics simulations. Specifically, the effects
of helium bubble internal pressure, bubble size, and layer thickness on the interface tensile yield strength and deformation mechanism of Cu/Nb layered materials are investigated.
Results show that interface helium bubbles can induce interface dislocation nucleation,
change the microstructural evolution, and significantly reduce the interface tensile yield
strength of Cu/Nb layered materials. The effect of helium bubbles on the interface tensile
yield strength weakens as the helium bubble size increases resulting in apparent size effect.
Compared with the case without helium bubbles, the interface tensile yield strength reduced
by approximately 12% and 33% for the models containing 3 and 6 nm helium bubbles,
respectively. Additionally, the layer thickness minimally affects the upper yield stress of
the Cu/Nb-layered materials, whereas it significantly affects the lower yield stress. The
former is attributed to the structure symmetry of the Cu/Nb interface and the loading
symmetry, which render the interface stress and dislocation nucleation stress insensitive to
the layer thickness. The latter is due to the increased layer thickness, which provides more
space for dislocation motion and evolution, thus resulting in rapid stress reduction during
the yield period.
ZHANG Yaning1, 2, 3 , LU-CHEN Yangtao ¨ 1, 2, 3 , CHU Haijian1, 2, 3
. Atomistic simulation of the effect of helium bubbles
on interface tensile yield strength of Cu/Nb
layered material[J]. Journal of Shanghai University, 2024
, 30(5)
: 904
-912
.
DOI: 10.12066/j.issn.1007-2861.2523