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

The corrosion products Cu₂(OH)₃Cl, 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 Cu₂(OH)₃Cl and CuCl₂ was not identified. The sample developed after treating of the cooper surface in the sodium/magnesium chloride solution contains Cu₂(OH)₃Cl and CuCl₂ prevailing over the Cu₂O, while the sample developed after treatment of copper in sodium/calcium chloride solution contains Cu₂(OH)₃Cl prevailing over CuCl₂ and Cu₂O was not identified.