Investigation of atmospheric plasma spraying coated aluminum oxide on MS C40

Abstract

Thermal Barrier Coatings (TBCs) have advantages such as improved thermal efficiency and combustion, reduction in weight by eliminating cooling system. The problem presently faced in implementing of TBC as turbine blades is thermal mismatch which mainly occurs due to improper adhesion and difference in thermal expansion coefficients between bond coat and turbine material. In this work Atmospheric Plasma Spraying (APS) method is selected for the fabrication of the work piece. In the present work, Mild Steel C-40 is selected as substrate material. Commercially available Nickel Chromium (Ni-Cr) is selected as bond coat. For top coat Aluminium Oxide (Al2O3) is selected. Bond coat is done for 75μm. Top coat thickness is varied between 100-300 μm. APS ceramic coating is selected as it gives more importance to obtain the uniform thickness on the substrate. In this work the surface roughness is measured by using Handy Surf E-35A type portable surface measuring instrument, Morphology of the above TBC system are studied with the help of scanning electron microscope, Coating thickness is done by using image analysis technique, X-Ray Diffraction for phase analysis for sample with the help of D8 Advanced (Bruker AXS), The porosity measured by using image analysis software and Microhardness of each layer of coating is measured by using Clemex CMT.HD Microhardness tester with a Vickers’s diamond indentation. In this work, the wear test has been performed on Pin-on-disc at, room temperature. From the results and discussion, it can be stated that coating shows good wear and heat resistance.