High Energy Pulsed Plasma Arc Synthesis and Material Characteristics of Nanosized Aluminum Powder

Abstract

Using a modified concept of an electrothermal gun powered by a high energy electrical pulse, aluminum nanopowder, whose average particle size ranges from 40 to I 10 nm, has been synthesized by discharging and quenching aluminum plasma arc vapor in the argon gas. The characterization of produced aluminum nanopowder has been performed by using SEM, TEM, BET, XRD, and SAXS, and the results show the spherical aluminum nanoparticles with an amorphous oxide layer of passivation whose thickness is 2 rim to 3 nm. Thermal analysis of 44 nm and 80 nm aluminum nanopowders using TG and DSC shows that the aluminum nanopowder with a smaller particle size has increased reactivity during oxidation, such as a lower oxidation onset temperature. However, as the average particle size becomes smaller, the active aluminum content decreases rapidly, so 80 nm to 120 nm-sized aluminum nanopowder might be useful as an energetic material.