Thermo-mechanical characteristics of oxide-coated aluminum nano-powder

Abstract

This paper presents a comprehensive study on the thermo-mechanical characteristics of oxide-coated aluminum nano-powder, which is a crucial property for their application in powder metallurgy, particularly in warm compaction process. A representative volume element (RVE) of oxide-coated aluminum nano-powder is analyzed under the hydrostatic compression test at different temperatures using the Reactive Molecular Dynamics (RMD) method that can predict the thermal conductivity of nano-powders by incorporating the interaction effects of density and temperature. The thermal conductivity is evaluated based on the Müller-Plathe's reverse non-equilibrium molecular dynamics (rNEMD) method, and the size dependence of the method is investigated. The computational model is validated with the experimental data. The results illustrate that the thermal conductivity of oxide-coated aluminum nano-powder is significantly lower than that of the bulk aluminum due to restricted surface contact between individual aluminum particles. Moreover, it is observed that increasing the density and temperature leads to an increase in the thermal conductivity of oxide-coated aluminum nano-powder.