Wear and corrosion performance of Stellite 6® coatings applied by HVOF spraying and GTAW hotwire cladding

Abstract

Abstract Different coating technologies imply a large variation in the properties of the deposited material. This work compares, for the first time, the wear and corrosion performance of Stellite 6® coatings applied onto substrates of low carbon steel by the Gas Tungsten Arc Welding hot-wire cladding and by High Velocity Oxygen Fuel spraying technologies. The impact of the microstructure and mechanical properties in the wear and corrosion results are also discussed. Slurry erosion tests are performed at two solid particles impact angles, 30° and 90°, and impact velocities of 3.61 and 9.33 m/s. Abrasive wear performance of the coatings was determined following the ASTM G-65-04 standard. Electrochemical impedance spectroscopy is applied for corrosion evaluation. HVOF sprayed coatings have performed better in abrasive wear while GTAW hotwire cladding coatings have shown higher resistance to erosive wear and better performance in corrosion tests.