Structural evaluation and deformation features of interface of joint between nano-crystalline Fe–Ni–Cr alloy and nano-crystalline Ni during creep process

Abstract

A molecular dynamic (MD) simulation has been performed to study the creep behavior and structural evaluation during creep process of nano-joint of nano-crystalline (NC) Ni and Fe–Ni–Cr alloy (18at.% Cr, 8at.% Ni and rest Fe) using EAM potential. A simulation box of 14.4×14.4×14.4nm dimension having 254,407 atoms is taken for performing MD simulation. MD simulation of creep of this nano-joint has been performed for different temperatures and different applied load. Centro-symmetry parameter (CSP) analysis, common neighbor analysis (CNA), radial distribution function (RDF), Wigner–Seitz defect analysis, and Voronoi cluster analysis (VCs) have been performed to study structural evolution during creep process. Dislocation also plays a role along with the grain boundary diffusion at least for primary and secondary regime of creep process of this nano-joint between NC Ni and Fe–Ni–Cr alloy. The average displacement of the atoms in the regions (±1nm, ±2nm, and ±3nm) adjacent to the interface during creep process is calculated using traction and separation method to study the atomic movement near the interface. The atoms are observed to be displaced more which are nearer to the interface during creep of this nano-joint system.