Corrosion behaviour of bronze protected by organosilane coatings: Influence of alloying elements and phase composition

In this study the corrosion behaviour of bronze has been compared to that of both the alloying elements and the alloys reproducing the composition of the dendritic and interdendritic phases. The results show that in bronze selective dissolution of Pb globules occurs. Moreover, bronze is affected by the galvanic corrosion of copper-rich dendritic regions stimulated by the nobler tin-rich interdendritic phase. When 3-mercaptopropyl-trimetoxy silane (PropS-SH) is applied on bronze the practical nobili-ty of the interdendritic zones remains higher than that of the dendrite cores, but the galvanic activity of both regions is greatly reduced.