Properties of HVOF Coating of Ni Based Alloy for MSWI Boilers Protection

摘要

Steel tubes oxidation causes an important problem inMunicipal Solid Waste Incinerator plants (MSWI). This workshows a possible solution for this problem through HighVelocity Oxygen Fuel (HVOF) thermal spray coatings. Acomparison between powder and wire thermal spray coatings(with the same composition) has been done. These optimisedcoatings have been compared through their microstructure,wear properties (ASTM G99-90, ASTM G65-91), anderosion-corrosion (E-C) resistance. Results of the different ECtests designed in the Thermal Spray Centre, have beenevaluated by X Ray Diffraction (XRD), Scanning ElectronMicroscopy (SEM) and Energy Disperse Spectroscopy (EDS).Commercial bulk material with similar composition of NiBased coatings has also been tested. The protectionmechanisms of these materials have been assessed afterstudying the results obtained by HVOF coatings and bulkmaterial. Ni based HVOF coatings are a promising alternativeto the MSWI conventional protection against chlorineenvironments.