Influence of Stress on Creep Behavior of Ni60Zr40 Glass-Reinforced Ni Nanocomposite Investigated by Atomistic Simulations

摘要

In this present study, molecular dynamics simulations of creep deformation at 1200 K temperature and different stresses have been performed to study the influence of stress on the creep behavior of Ni60Zr40 glass-reinforced nanocrystalline (NC) Ni nanocomposite using embedded atom method potential. Adaptive common neighbor analysis, centro-symmetry parameter estimation, Voronoi polyhedra, atomic trajectory and radial distribution functions are implemented to present structural evolution during creep process, thereby providing an insight into the underlying mechanism. The specimen is observed to undergo substantial amorphization with the progress of creep deformation owing to stress-induced diffusion of Zr atoms to NC Ni through the Ni60Zr40 glass-NC Ni interface and thickening of grain boundaries, which eventually causes a negative creep phenomenon at the later stage of tertiary creep regime. Calculated stress exponent for Ni60Zr40 glass-reinforced nanocrystalline (NC) Ni nanocomposite is equal to 0.64.