Effect of Ar pressure on the wettability of copper droplet on graphite substrate by molecular dynamics simulation

Understanding the wetting behavior of copper droplet on graphite substrate has important engineering significance for guiding the preparation of Cu/graphite (Cu–C) composite materials. This paper used the molecular dynamics simulation method to analyze the wetting behavior of Cu droplet on the graphite substrate with different Ar pressures at the atomic scale, which ranged from 0 to 3 atm. The molecular dynamics simulation results indicated that for temperatures below 1300 K, Ar pressure hindered the wetting of droplet, while for temperatures above 1300 K, Ar pressure promoted the wetting process of droplet on the graphite substrate. However, in systems with Ar pressure higher than 1.2 atm, the improvement of wetting by Ar pressure no longer increases. In addition, Ar pressures increased the potential of mean force of Cu droplets leaving the graphite substrates, making it more difficult for droplets to detach from the substrates.