The electropolishing of copper

Abstract

An optical technique was used to study the anodic surface films produced during the electropolishing of copper. An 'in situ' experiment had to be devised as these films are destroyed when the anode is removed from the electrolyte. White light was reflected from the anode surface through the surface films and the reflected light analysed. The spectrographs recorded whilst the anode was being electropolished were compared with those obtained whilst the anode was being etched, to try and detect any excess absorption during electropolishing. The differences in the spectrographs are discussed in detail. However the results are inconclusive since it could not be ascertained that the differences were due solely to the anodic surface films.