Characterization of the WC coatings deposited by plasma spraying

Tungsten monocarbide (WC) is deposited using a plasma jet on the martensitic noncorrosive steel support (Z12CNDV12), in three different thicknesses. The characteristics of the coatings are determined by: its chemical composition, optical microscopy, RX analysis, tensile adhesion strength, Vickers hardness, the nature and the processing degree of the substrate and the deposition conditions. The method used for determining the behaviour in a corrosive environment of the WC coatings deposited by plasma spraying consists in measuring the electrochemical potential difference between the coating and the substrate, which are immersed in a solution containing NaCl as a corrosive agent. The experimental results are then mathematically processed in order to determine a law and the mechanisms involved.