Designing for Optimum Use of Plasma Coatings

Abstract

Plasma coatinhs are primarily designed to protect materials from wear, heat corrosion (with sealer), and abrasion. Over the past few years, efforts to develop plasma sprayed coatings have been extensive. Because the properties of coatings vary considerably from those of conventional wrought and cast materials, coatings can be successful only if they are properly chosen, controlled, and tested. This paper shows how the judicious selection of plasma coatings is based on knowledge of coating characteristics, advantages, and limitations and on field experience. Strict control of the powder, the process, and the end product is essential. The best coating results depend on the composition, microstructure, shape, and size distribution of the initial powders. The plasma parameters and spraying techniques also contribute significantly to the quality of the coatings.