OPTICAL DETERMINATION OF CUPROUS-OXIDE AT ZINC-OXIDE METAL INTERFACE OF AN OXIDIZED ALPHA-BRASS

During brass oxidation, a copper diffusion is observed at the zinc oxide/metal interface, in the case of high temperature oxidation (T > 400-degrees-C). Optical methods like FTIR and photoluminescence are used to characterize the oxidized form of copper located at metal-oxide interface. Detection of the vibrational transverse mode at 610 cm-1 and luminescence emissions attributed to copper and oxygen vacancies allow the characterization of copper oxidized form (copper I oxides) located at metal/oxide interface in agreement with SIMS results. But, the displacement reaction (Cu2O + Zn --> 2 Cu + ZnO) could also occur according to thermodynamic data; so, the copper is in the oxidized form and eventually metallic.