High performance surface engineering from plasma spraying

Abstract

The continuing trends in engineering are to increase component productility, reliability and lifetime. For example, the emphasis in turbine engine technology is to raise engine ratings, reduce fuel consumption and generally higher efficiency levels. In addition to advances in mechanical engineering and materials technologies, these increases are being gained by the use of a coating technology based on the concept that the substrate provides the mechanical strength and the coating sufficient protection to inhibit the environment. Plasma spraying is a coating technology producing surface layers from materials in powder form. Machine tooling for the production of plasma sprayed coatings onto engineering components in an economic and consistent manner requires proper equipment selection in connection with both the surface preparation (grit blast) and the subsequent deposition process of coating. This paper reports on the status of plasma spraying for a variety of industries and in particular on the types of machine tooling required together with the level of sophistication for the preparation and deposition of plasma sprayed coatings.