UV-irradiation assisted corrosion protective oxides film on pure Sn solder substrate exposed to atmospheric environment

Although studies on UV-irradiation induced corrosion evolution of pure Sn or its alloys in electrolyte environments are available, the structural evolution of atmospheric corrosion-induced oxides film on Sn solder surface under the effect of UV-irradiation has rarely been reported. In this investigation, the UV-irradiation induced evolutions in corrosion resistance and structural changes in the surface oxides film on pure Sn solder substrates have been studied. The electrochemical tests show that more than 50 % increase in corrosion resistance of the surface oxides film, exposed to atmospheric environment under the effect of UV-irradiation, has been found. XPS characterization indicates that the UV-irradiated sample has a higher SnO2 content in the surface oxides film than the sample without UV-irradiation, and it is thus supposed that the accelerated oxidation of SnO to SnO2 caused by UV-irradiation is responsible for this. Such an interesting finding will pave a new way in surface treatment technologies for corrosion protection of Sn and its alloys.