Molecular dynamics based study of high temperature deformation process of nanocrystalline Ni-Nb alloy under tensile loading condition

High temperature deformation behaviour of nanocrystalline (NC) Ni-Nb alloy having Nb segregated at grain boundary with various percentages (4, 8 and 10 at. % Nb) are studied using molecular dynamics (MD) simulations. All the simulated tensile tests for NC Ni-Nb alloy are carried out at 800 K temperature with 10(8) s(-1) strain rate. NC Ni-Nb alloy specimens having 14.04 nm x 14.04 nm x 14.04 nm simulation box dimension contains 16 numbers of grains and 254,348 atoms. Average grain size of NC Ni-Nb alloy specimen is taken as 6 nm. Centro-symmetry parameter, dislocation density, number of vacancy and Radial distribution function have been carried out to study structural changes under tensile loading condition. Strength of NC Ni-Nb specimens are found to be significantly enhanced with increasing percentage of Nb atoms. Flow stress of NC Ni-Nb specimens are found to be increased with increasing percentage of Nb atoms. (C) 2019 Elsevier Ltd. All rights reserved.