M Tavakoli - Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
M Mahnama - Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
R Naghdabadi - Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran- Institute for nano science and technology, Sharif University of Technology, Tehran, Iran

Effect of temperature on the microstructural evolution in nickel nanoparticle during the sinteringprocess is investigated by molecular dynamics (MD) simulations. For this purpose, nickel nanoparticles are chosenat the size of 8.2 nm that is appropriate to get a variety of evolution mechanisms during the sintering process. Thesintering temperature is varied within the range of 600 to 1500 K that is below the melting temperature of nickelnanoparticles in this size. The simulation results emphasize on the difference in the driving force of the sinteringprocess under different temperatures. It is concluded that while in micron-sized particle sintering the diffusioneffect takes the main role in the process, in nano-sintering some other mechanisms are also triggered. It is shownthat depending on the material energy level, both diffusion and dislocation motion mechanisms are activated inthe nanosintering; at low temperatures the main mechanism is the motion of dislocations, however at highertemperatures the main mechanism switches to the surface diffusion.

Sintering; Mechanism; Nickel; Nanoparticle; Molecular Dynamics