X-ray diffraction phase analysis of crystalline copper corrosion products after treatment in different chloride solutions

The corrosion products Cu-2(OH)(3)Cl, Cu2O, and CuCl2 were identified on the surface of copper plates after their four days treating in three different sodium chloride, sodium/magnesium, and sodium/calcium chloride solutions using X-ray diffraction powder analysis. However, the quantitative proportions of individual corrosion products differ and depend on the type of chloride solution used. Treating of copper plates only in the sodium chloride solution produced the mixture of corrosion products where Cu2O is prevailing over the Cu-2(OH)(3)Cl and CuCl2 was not identified. The sample developed after treating of the cooper surface in the sodium/magnesium chloride solution contains Cu-2(OH)(3)Cl and CuCl2 prevailing over the Cu2O, while the sample developed after treatment of copper in sodium/calcium chloride solution contains Cu-2(OH)(3)Cl prevailing over CuCl2 and Cu2O was not identified. (C) 2002 Elsevier Science Ltd. All rights reserved.