EFFECT OF HVOF DEPOSITION PROCESS IN POWDERS OF TUNGSTEN CARBIDE WITH DIFFERENT BINDERS

摘要

The production of hardened surfaces on components to increase the wear resistance is a persistent technological challenge in the field of Surface Engineering. HVOF (High Velocity Oxygen Fuel) thermal spray process is used to produce coatings with high resistance to the wear and/or to the corrosion. Tungsten carbide with a metallic binder is often used for this purpose. In this work, coatings of tungsten carbide with cobalt binder or nickel binder were produced by HVOF process and characterized by optical and electronic microscopy tests, hardness and density tests and X-ray diffraction analysis. The HVOF process produced dense coatings with low porosity levels and high average hardness, about 1100 HV. The HVOF deposition process did not significantly deteriorate the powders used.