Corrosion and wear analysis of HVOLF sprayed WC-10CO-4Cr coating on geothermal turbine blade

Abstract

Purpose The purpose of this paper is to develop the high pressure high-velocity oxy-liquid fuel sprayed WC-10Co-4Cr coatings on geothermal turbine 9Cr-1Mo steel for protection against wear and corrosion. Design/methodology/approach The microstructural characterization of as-deposited and corroded coating was done and presented using X-ray diffraction and scanning electron microscope/energy dispersive spectroscopy analysis. Findings The developed coating offered 50 per cent enhanced microhardness (1,200 HV) and 100 per cent enhanced wear resistance, in comparison to bare geothermal turbine steel, respectively. The coating has shown enhanced life in the simulated working conditions (fog test and dip test). This may be because of the high microhardness of the developed coating as per the proven tribological theories. Originality/value Coating offered excellent corrosion resistance in the harsher simulated environments to geothermal turbines.