Remelting of Thermal Spraying Coatings - Technologies, Properties and Applications

Abstract

The most popular spraying technologies include: flame spraying, arc spraying and plasma spraying. Spraying technologies allow for the formation of coatings with a desired chemical composition and thickness. However, such coatings characterize by numerous imperfections associated with the nature of the process itself. It is obvious that some of imperfections in thermal spraying coatings can be eliminated by choosing the right parameters of the process. However, in order to improve the properties and eliminate material discontinuous, it is necessary to conduct the remelting process. Research in most cases, showed that the reduction of porosity and simultaneous increase in hardness are possible only by remelting the coating using different heat sources. By adjusting the technological parameters and remelting speed, it is possible to precisely control the depth of the remelted material and thus the properties of final coatings. The paper presents the remelting processes of thermal spraying coatings in relation to technologies, properties and applications.