Abstract:

Thermal barrier coatings (TBCs) are a type of coating used to provide thermal insulation in critical zone parts exposed to high temperatures, such as combustion chambers and turbine blades of gas turbine engines in the aviation industry. With the use of TBC systems, it is ensured that the surface temperature of metallic parts is increased and the efficiency of the turbine is increased, and the longer service life is achieved. The metallic material used as a substrate for a typical TBC system has a combination of metallic bond coating with MCrAlY content and yttria-stabilized zirconia coating (YSZ). In this study, metallic bond coatings with CoNiCrAlY content on Inconel 718 superalloy substrate were produced using atmospheric plasma spray (APS) coating method with a thickness of approximately 100 μm. CaO stabilized zirconia (CSZ) and MgO stabilized zirconia (MSZ) top ceramic coatings of TBC systems were produced using the APS method with a thickness of approximately 300 μm. Post-production microstructural and mechanical properties of different TBC systems produced were comparatively investigated and evaluated. Microstructural properties, and phase structures of the coatings were determined using scanning electron microscopy (SEM), elemental mapping, and X-Ray Diffractometry (XRD) analysis. Also, apart from microstructure and phase structures, porosity, hardness, and surface roughness properties were measured. The obtained analysis results, findings, and TBC systems were evaluated comparatively in the light of other relevant studies in the literature.

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