Thermal stabilities of iron nanoparticles under hydrostatic pressure

Abstract

The present study aimed to apply molecular dynamics simulation to study the thermal stability and melting behavior of bcc iron nanoclusters under the pressure of up to 40 GP. Several factors were calculated, including the bulk modulus, melting temperature, melting enthalpy changes, melting volume changes and radial distribution function. In addition, size effects were investigated in the melting process. The bulk modulus was observed to raise a thigh external pressure and decrease in enlarged sizes. Pressure and size were significant determinants of the melting temperature. In the melting process, rate of enthalpy changes increased with greater pressure and size, while the volume changes reduced at higher pressure and size. On the other hand, small nanocluster size augmented the ΔVm slope. Finally, g(r) values of the first shell declined with greater nanocluster sizes, and iron atoms appeared closer in the nanocluster structure at high pressure.