Oxidation Behaviour of a Newly Developed Superalloy

I.V.S. Yashwanth, I. Gurrappa, H. Murakami

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DOI: 10.4236/jsemat.2011.13020                

Abstract

The current paper explains the oxidation behaviour of a newly developed nickel-based superalloy in simulating aero gas turbine engine conditions. The results showed that the new superalloy is highly susceptible to high temperature oxidation. Within three of hours of oxidation, extensive oxide scales were formed. The formed oxide scales were ana-lysed with electron dispersive spectroscopy (EDS) and morphology was studied with scanning electron microscope (SEM) for varied oxidation times. The oxidation products were determined with XRD and cross sections of all the oxi-dised superalloys were also studied. The elemental distribution of all the superalloys after oxidation was also studied with a view to understand and compare the characteristics of the new superalloy with other superalloys. Finally, an oxidation mechanism that is responsible for its faster degradation under elevated temperatures was established based on the results obtained with different techniques and presented in detail.

Keywords

Gas Turbine Engine Components, Superalloys, High Temperature Oxidation

Conflicts of Interest

The authors declare no conflicts of interest.

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