Surface modification of plasma-sprayed alumina deposits by high-energy ionbeams

This paper reports on characteristics of alumina-type coatings deposited on steel substrates and treated with pulsed plasma streams containing high-en ergy ion beams (N, Ar, and Ti+N). Originally matted surfaces of the ceramic layers, which were created by plasma spraying of gray alumina, were change d 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 mum. A higher content of Ti was found on the surfaces of the Ti- and N-trea ted samples only.