Improving the Chemical and Physical Properties of Ceramic Non-conductive Coatings

Commercially available plasma-sprayed ceramic non-conductive coatings (NCC) are utilized in numerous applications including, aviation, industrial, structural and electronics. The research being presented in this study focuses on how ceramic NCC can be used to prevent cathodic delamination on underwater platforms. This technology was not originally developed for that purpose; thus many of its chemical and physical parameters have not been optimized for defeating cathodic debonding. Issues being studied include the need for, and chemical composition of, the metal interface layer between the ceramic and the substrate, the effect of plasma-spray techniques and materials on porosity within the ceramic layer; methods for ensuring full adhesion between multiple ceramic layers; optimized chemical compositions for the seal-coat; and the effects of long-term storage on NCC bondability. The end result of the effort will be a more-reliable coating that will impart the maximum level of protection to polymer-metal interfaces subject to cathodic delamination. This work is part of a multi-year effort and this paper will focus on the work done associated with seal coat optimization and improvement.