Power law scaled hardness of Mn strengthened nanocrystalline Al-Mn non-equilibrium solid solutions

In this work, the effects of Mn on lattice parameter, electron work function (EWF), bonding charge density, and hardness of nanocrystalline Al-Mn non-equilibrium solid solutions are investigated. We show how the enhancement of the EWF contributes to the observed improvement of the hardness of Al-Mn solid solutions. It is understood that the physical mechanisms responsible in our model, using the EWF coupled with a power law scaled hardness, are attributed to the redistribution of electrons caused by the presence of Mn solute atoms, supporting an atomic and electronic basis for the coupling of solid solution and grain refinement strengthening mechanisms.