Effect of aluminum nanoparticle size on phase transitions: a molecular dynamics study

Isothermal molecular dynamics simulations were carried out with the embedded-atom method as a potential to predict the melting and crystallization temperatures of nanometric sized aluminum particles in the range of $$2$$ 2 – 4 nm 4 nm . Simulated data predicted a decrease in the melting point Tₘ T m of aluminum nanoparticles with an increase in their inverse radius r⁻¹ r - 1 according to an almost linear law. The data obtained predicted a higher value of melting temperature compared to crystallization by Δ T=272 K Δ T = 272 K for a size of 4 nm 4 nm and, Δ T=193 K Δ T = 193 K for 2 nm 2 nm . The Tₘ T m of the nanoparticles augmented with increasing size, from $$720 K$$ 720 K for 2 nm 2 nm to 827 K 827 K for 4 nm 4 nm . Furthermore, a linear extrapolation of the Tₘ T m as a function of the inverse of the cubic root of the number of atoms yielded a melting temperature of aluminum of 947 ± 8 K 947 ± 8 K , which is similar to previous estimations. Finally, when the number of atoms increased the number of face-centered cubic (FCC) structural units also increased, and the amorphous structure decreased.