Simplified monitoring of atmosphere by FT-IR measurements of corroded copper plates

Copper plates were exposed to the ambient atmosphere at different locations in the Chugoku district in order to compare metal corrosion in the three distinct regions of the Tsuyama basin, San-in (Tottori), and San-yo (Okayama). The samples were analyzedat regular intervals by FT-IR reflection absorption spectroscopy. Some species of Cu2O, CuO, hydroxy and sulfato complexes were found on the surfaces of copper plates. Thesamples exposed from December of 1992 to April of 1993 in the Tottori district were more corroded than those in Okayama City. Most of the copper plates exposed in the Tsuyama basin were noncorroded except for a couple of samples from the east part of the basin. The results of the FT-IR spectra also revealed that there were some points in the eastern part of the Tsuyama basin where corrosion of copper plates was similar to that in the Tottori district. This might be attributed to a temporary lull in seasonal westerlies around the eastern part of the Tsuyama basin.