The Chemistry of the Corrosion of Electrodeposited Tin Finishes

Within this thesis the chemistry of the corrosion of electrodeposited tin finishes under high-temperature and high-humidity conditions (80 °C / 80 % relative humidity) was investigated.

The first section covers the differences in the corrosion propensity of electrodeposited tin finishes in dependence on their manufacturing process and the development of a structural model utilizing the surface energies of ß-tin in order to minimize the corrosion and the tin whisker propensity.

The second section examines the chemical processes on the tin surface during the exposure to high-temperature and high-humidity conditions avoiding a direct contact of the metal surface to an electrolyte solution. In dependence on the contaminant (sodium halides) the corrosion sequence was clarified utilizing in situ Raman spectroscopy.