Molecular dynamics simulation of nano-sized single crystal Iridium deformation behavior

Due to the good physical and chemical properties, single crystal Iridium has a wide range of applications. However, the existing study about the deformation behavior of nano-sized single crystal Iridium is little. In the present paper, the nano-sized single crystal Iridium under uniaxial tension and different strain rate is simulated by using the molecular dynamics. The calculated results indicate that the variation of strain rate has influence not only on the elastic stage but also on the plastic stage, and has more influence on the plastic stage. Different strain rate leads to different deformation mechanism. When the strain rate is below 0.0003 ps^-1, the variation of strain rate has no significant effect on the mechanical properties of the crystal and it exhibits brittle fracture. While the strain rate is greater than 0.0004 ps^-1, the deformation mechanism changes from brittle fracture to low plastic fracture. When the strain rate exceeds 0.001 ps^-1, nano-sized single crystal Iridium slips along (1̄10) plane, and there is some necking near the fracture.