Investigation of solid particle erosive wear behaviors of WC-Co and NiCr coatings produced with HVOF

Today, the interest in the production of high-performance materials in terms of their chemical, physical, and mechanical properties is increasing day by day. With the utilization of thermal spray coating technology in the field of surface engineering, the service life of parts in industrial use against damages such as wear, oxidation, corrosion, and thermal shock can be significantly increased. Thermal spray coatings have a wide range of uses, from automotive to aviation, from the chemical industry to aerospace and defense technologies. Like other mechanical and tribological factors, solid particle erosive wear (SPE) causes damage to parts and components used in industry as a result of plastic deformation, starting from the material surface. Given the wear-related conditions to which the parts used in the machinery industry are subjected, it is critical that the parts remain operational without being damaged during short cycle periods. Wear and abrasion resistant coatings are carried out using thermal spray coating methods, especially the high velocity oxy-fuel (HVOF) spray technique. This method allows the production of coatings with less oxide, lower porosity content, and high hardness values. In the study, which constitutes the main content of the master's thesis, coatings with WC-Co and NiCr content on 316L stainless steel substrates were produced using the HVOF technique. The SPE behavior of the produced coatings was examined in detail, and SPE experiments were carried out using different impact angles and alumina (Al2O3) abrasives with different particle sizes. Studies conducted in the literature and the findings obtained were evaluated comparatively, and inferences were drawn. As a result of the studies, it was observed that the materials with the WC-Co coating exhibit brittle surface properties against solid particle erosion, while the materials with the NiCr coating exhibit ductile surface properties. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy distribution spectrometry (EDS) and 3D profilometer analysis measurements were taken from advanced characterization techniques in order to detect and make detailed evaluations of the coated and eroded surfaces after the experiments. With the findings obtained, a positive contribution has been made to the current literature in terms of production, SPE behavior, and damage formation in systems with different coatings.