Surface modification of plasma sprayed alumina deposits by high-energy ion beams

This paper reports on characteristics of alumina-type coatings deposited on steel substrates and treated with pulsed plasma streams containing high-energy ion beams (N, Ar, and Ti+N). Originally matted surfaces of the ceramic layers, which were created by plasma spraying of gray alumina, were changed into shiny ones, and splat boundaries disappeared due to the melting of a thin surface layer. The thickness of this modified layer did not exceed 1 μm. A higher content of Ti was found on the surfaces of the Ti- and N-treated samples only. (author)