Reaction behavior of shock compressed aluminum and iron-oxide powder mixtures

Fine and coarse morphology powders of Al-Fe2O3 and Al-Fe3O4 mixed in an equivolumetric distribution were shock compressed at different packing densities and loading conditions. Compacts of powders packed at 53% TMD and shock-compressed using Momma Bear A fixture and Baratol explosive (P∼16 GPa) underwent complete reaction, while no reaction was observed when the same powders were shock compressed at lower pressures (P∼5GPa) using Poppa Bear fixture and Baratol explosive. The Al-Fe2O3 mixtures were also shock-compressed using a higher 70% TMD packing density. No reactions were observed for MBA-B (P∼16 GPa) while MBA-CB (P∼22 GPa) showed complete reaction. The microstructure of the cross-section of the fully reacted samples showed features of melting and solidification, with an Al-Fe intermetallic core and an aluminum oxide layer surrounding it. The unreacted compacts consisted of heavily deformed aluminum particles and iron oxide particles that were fractured (with cracks oriented along the shock direction...