Surface studies on the thermite mixture of Al/Cu/sub 2/O. I. Auger and x-ray photoelectron results using Si K/sub. cap alpha. /x-radiation

Abstract

Thermite is the name given to a mixture of powdered aluminum and a metallic oxide. When a thermite mixture is ignited the chemical reaction proceeds very rapidly with a great evolution of heat, the temperature rising to around 2000/sup 0/C. Uses for the thermite reaction have been found in metallurgy, in immobilizing radionuclides, and in military applications. The surface chemistry of the thermite materials, aluminum and copper powders, were examined with Auger and x-ray photoelectron spectroscopy also referred to as Electron Spectroscopy for Chemical Analysis (ESCA). This preliminary study was made to show the feasibility of ESCA in examining the surface chemistry of the thermite materials. The surface of the aluminum metal powder was found to be contaminated with an oxide. The oxide was characterized to be Al/sub 2/O/sub 3/, and the oxide layer was found to be approximately 20A. A zinc contamination layer, approximately 300A thick, was noted on the copper. The oxidized species on the copper powder was characterized to be Cu(OH)/sub 2/. The change in the binding energies and differences in the Auger parameter for aluminum and its oxide and copper and its oxides were substantial, making the ESCA technique useful in studying the Al/Cu/sub 2/O thermite.