In situ TM-AFM investigations of the influence of zinc and tin as alloy constituents of copper to the early stages of corrosion

To obtain information about the changes in the topography of sample surfaces during weathering, in situ tapping mode atomic force microscopy (TM-AFM) was used for the investigation of the early stages of corrosion of binary copper/zinc (brass) and copper/tin (bronze) alloys. The emphasis of these investigations is to state the shape and lateral distribution of the corrosion products grown within the first 1300 min of weathering. Investigations were carried out in synthetic air with 80% relative humidity (RH) and 80% RH with 250 ppb SO 2. While brass shows a homogeneous growth of features forming a surface film during weathering in 80% RH, the features on the bronze surface reveal a higher growth rate of a few sparsely distributed features.