[P1-30] The atomic study of tensile property for nickel nanowires with helium bubble
Tensile deformation behavior of nickel nanowires with helium bubble has been investigated using molecular dynamics (MD) simulation. MD simulations were performed at 1K to 300K employing a strain rate of 2×109s-1 and 2×1010s-1 for the nanowires with cross section width(S)ranging from 8a0 to 12a0(a0=3.5157Å). The diameters were set from 1.2 nm to 1.6nm for helium bubbles, and the ratio of helium-to-vacancy inside bubble for 1:1, 2:1, 4:1 and 1:0. With the strain rate increasing, the elastic modulus and yield stress are also increased. However, they present the declined trend at the high temperature. As the helium bubble size increases or the cross section of nanowires decreases, the elastic modulus and yield stress increases, while the yield strain become smaller. In addition, the mechanism of yielding is discussed in details based on the snapshots of defects evolution. As the radio of helium-vacancy increases, the elastic modulus and yield stress also decrease. The helium bubble could accelerate the fracture to some extent. This study on the plastic properties of metal nanowires will be helpful to further understanding of the mechanical properties of nanomaterials.