An XPS and AES study of the free corrosion of Cu-, Ni- and Zn-based alloys in synthetic sweat

Abstract This paper deals with the investigations into the behaviour during free corrosion of Cu/Zn/Ni, Cu/Ni/Zn and Ni/Cu alloys in a synthetic sweat medium by means of surface analyses. For the three alloys studied, our experimental results indicate the presence of a corrosion layer, the thickness of which increases with the increase of the copper content of the alloy. The corrosion layers are composed of Cu- and Ni-based compounds. For the alloys with a high Cu content, the latter is mainly composed of copper (I) oxide in which chloride anions are included. For the alloys with a high Ni content, Cu 2 (OH) 3 Cl and Ni-compounds like Ni (OH) 2 and NiO are detected in the corrosion layer.