In this study, the effect of the coating process and heat-treatment cycles on the microstructural, mechanical, and tribological properties of NiCrBSi coatings deposited by High-Velocity Oxygen Fuel (HVOF) and High-Pressure High-Velocity Oxygen Fuel (HP-HVOF) techniques were investigated. The metallographic assessments, Energy Dispersive x-ray Spectroscopy (EDS), x-ray Diffraction (XRD), microhardness measurements, and nano-indenter tests were run on the as-sprayed and heat-treated coatings. The tribological properties were assessed using ball-on-disk wear test. The worn surfaces were observed using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The results of the nano-indentation test indicated that the Young\\\\\\\'s modulus of the coatings increased through the heat-treatment up to 20%. The tribological measurements indicated that the wear resistance of the as-sprayed HP-HVOF coating was 60% greater than that of the HVOF due to improved metallurgical properties and optimal hardness to Young\\\\\\\'s modulus ratio. Moreover, heat-treatment of the HVOF coatings at 950 °C for 1 h increased the wear resistance up to 50%, while increasing temperature up to 1000 °C caused a decrease in the wear resistance because of the considerable reduction in the microhardness. The worn surface studies revealed the existence of tribo-oxidation and abrasion as the main wear mechanisms involved in all samples.

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