Purpose: In this paper the results of high temperature cyclic oxidation tests of the protective diffusion coatings were presented. One of the main purposes of this work was to produce three different types of protective coatings by three different methods, i.e. slurry method, vapour phase aluminizing (VPA) and chemical vapour deposition (CVD), applied on nickel based Rene 80 superalloy substrate. Design/methodology/approach: The high temperature cyclic oxidation tests were carried out in 23h cycles at constant temperature 1100°C using Carbolite CWF 1300 chamber furnace. The samples were removed outside and were weighted after each cycle. The microstructure investigations of all kinds of the coatings were conducted by the use of light microscope (Nikon Epiphot 300) and a scanning electron microscope (Hitachi S-3400N). In the analysis influence of each method have been taken into consideration, i.e. especially influence of the kind of process on microstructure, coating thickness, chemical composition, first of all aluminium content (in outer β-NiAl layer so-called additive layer, diffusion layer and substrate). For the chemical composition examination x-ray energy dispersive (EDS) method was applied using Thermo equipment. Findings: It was found that the best high cyclic oxidation resistance of coating was obtained using CVD method (the maximal increase of samples weight after 28th cycle was observed, whereas in case of the slurry sample after 3rd and VPA after 5th). Research limitations/implications: The research results will be used in the future in order to increase coating thickness, aluminium content and to produce Pt, Pd, Zr, Hf and Si modified aluminide coatings. Practical implications: The CVD method will be used to coat internal passages of turbine blades, for example to produce modified aluminide bond coats on single crystal nickel based superalloys. Originality/value: Chemical vapour deposition is an unique method which is a “pure method” and allows to coat hardly accessible locations/areas.
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