Investigation on wear behaviour of SS 316L, atmospheric plasma and high velocity oxy-fuel sprayed WC-Cr3C2-Ni coatings for fracturing tools

The application of WC based coatings could minimise the failure of fracturing tools during downhole drilling and hydraulic fracturing. The oil and gas industries are experiencing maintenance challenges due to excessive wear caused by fracturing fluid containing a high concentration of proppants. The tribo-behaviour of atmospheric plasma spray (APS) and high-velocity oxy-fuel (HVOF) deposited WC-Cr3C2-Ni coatings on SS 316L substrate were investigated. The uncoated and coated specimens comparatively studied in dry sliding and oil-based fracturing fluid conditions. The characterisation of coatings for surface morphology, porosity, and nano-hardness was carried out. The ball-on-disc tribometer (ASTM G99) used for tribo-tests with Al2O3 balls as a counter body against uncoated and coated specimens. The experimental analysis suggested that both coatings revealed higher hardness and improved anti-wear characteristics compared with uncoated specimens. Moreover, for detailed information about wear mechanisms, the worn-out surfaces of uncoated and coated specimens were studied. Consequently, the outcomes show the potential use of WC-Cr3C2-Ni coatings to enhance the performance and lifespan of fracturing tools operating in hostile conditions, which is essential in economic savings during maintenance and replacement of components.