Coatings Probed by Positrons

Thin film coatings such as TiN and polymers (paint) have been studied using positrons. Positrons provide information on defect structure. It is shown how the positron response is related to properties of the coatings such as stoichiometry. Further positrons provide a measure of the uniformity of the coating. Preliminary results on the effect of weathering (ultraviolet exposure) of polymer protective coatings are very encouraging