Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 2 of 2
Full-Text Articles in Mechanical Engineering
Mechanochemical Mechanism For Fast Reaction Of Metastable Intermolecular Composites Based On Dispersion Of Liquid Metal, Valery I. Levitas, Blaine W. Asay, Steven F. Son, Michelle Pantoya
Mechanochemical Mechanism For Fast Reaction Of Metastable Intermolecular Composites Based On Dispersion Of Liquid Metal, Valery I. Levitas, Blaine W. Asay, Steven F. Son, Michelle Pantoya
Steven F. Son
An unexpected mechanism for fast reaction of Alnanoparticles covered by a thin oxide shell during fast heating is proposed and justified theoretically and experimentally. For nanoparticles, the melting of Al occurs before the oxide fracture. The volume change due to melting induces pressures of 1–2 GPa and causes dynamic spallation of the shell. The unbalanced pressure between the Al core and the exposed surface creates an unloading wave with high tensile pressures resulting in dispersion of atomic scale liquid Al clusters. These clusters fly at high velocity and their reaction is not limited by diffusion (this is the opposite of …
Melt Dispersion Mechanism For Fast Reaction Of Nanothermites, Valery I. Levitas, Blaine W. Asay, Steven F. Son, Michelle Pantoya
Melt Dispersion Mechanism For Fast Reaction Of Nanothermites, Valery I. Levitas, Blaine W. Asay, Steven F. Son, Michelle Pantoya
Steven F. Son
An unexpected mechanism for fast oxidation of Alnanoparticles covered by a thin oxide shell (OS) is proposed. The volume change due to melting of Al induces pressures of 0.1–4GPa and causes spallation of the OS. A subsequent unloading wave creates high tensile pressures resulting in dispersion of liquid Al clusters, oxidation of which is not limited by diffusion (in contrast to traditional mechanisms). Physical parameters controlling this process are determined. Methods to promote this melt dispersion mechanism, and consequently, improve efficiency of energetic nanothermites are discussed.