Effects of the High Temperature Annealing on Structure of the High Velocity Oxygen Fuel Deposited WC-Co Coatings


  • Šarūnas MEŠKINIS∗, Judita. PUIŠO, Algis JURAITIS, Viktoras GRIGALIŪNAS, Sigitas TAMULEVIČIUS, Romualdas JAKUTIS, Arūnas BABILIUS Kaunas University of Technology


WC-Co; HVOF deposition, protective coatings, high temperature air annealing, XRD, SEM.


In this study tungsten carbide/cobalt (WC-Co) coatings sprayed by high velocity oxygen fuel (HVOF) deposition were
investigated. For the comparative purposes the bulk WC-Co sample cutted from the WC-Co hot roller was studied as
well. It was found, that WC-Co bulk sample cutted from the WC-Co hot roller was coated by WO2 layer as a result of
the 900 °C temperature air annealing. No connection between the WC-Co coating oxidation and its peeling as a result of
the air annealing was found. The most stable coating in terms of peeling was the most oxidized one. According to XRD
analysis, formation of the surface oxide layer inhibits further oxidation of the deeper layer of the coating. Change of the
coating morphology was observed as a result of the air annealing starting at 500 °C temperature.