An insight into the temperature-dependent sintering mechanisms of metal nanoparticles through MD-based microstructural analysis

Carrying out molecular dynamics simulation, we have probed the final microstructure of sintered Cu-Ni nanopowders to introduce a route for finding out the optimal process parameters for metal nanoparticles. As such, a through microstructural analysis is conducted in each case to identify the atomic-scale evolutions in the interfacial region. Firstly, a reverse correlation is found between the solidification time and amorphous con-tent within the samples. It is revealed that in a temperature range of 600-1000 K, the process is controlled by the slip of dislocations. Meanwhile, beyond 1000 K, surface diffusion and thermal twinning are the main mecha-nisms. Finally, in the case of 100 ps sintering at 1000 K, the combination of dislocations slip and surface diffusion phenomena would result in creating a defectless structure, which introduces these values as the optimal param-eters. Moreover, by monitoring the temperature-dependent MSD diagrams, the sintering dynamics is deeply an-alyzed to complete the discussion. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study reveals a reverse correlation between solidification time and amorphous content, with the process controlled by dislocation slip at temperatures from 600-1000 K and by surface diffusion and thermal twinning beyond 1000 K. Optimal parameters are identified as a combination of dislocation slip and surface diffusion at 1000 K with 100 ps sintering. Temperature-dependent MSD diagrams are monitored for a detailed analysis of sintering dynamics.