Abstract
Thermal spraying is a widely used technology in a range of industrial applications to provide coatings improving the surface characteristics. According to the thermal and kinetic specificities of processes (APS, VPS, flame, electric arc), any kind of material can be sprayed. Among materials, ceramic coatings present several interesting aspects for wear resistance, corrosion protection as well as for thermal or electrical insulation; particularly alumina coatings which appear as the most commonly used. Many techniques can be used to spray such kind of materials. From all of them, atmospheric plasma spraying (APS) is a rather well-established process but some other processes can also be used with a lower economical impact as the flame technology. The aim of this study was to analyse the alumina coating properties according to the technology employed such as atmospheric plasma spraying or wire flame spraying using the Rokide and the Master Jet guns. After usual micrographic analyses by SEM, physical and mechanical properties were measured considering the thermal conductivity and the hardness.
