Overview of mechanical, microstructural, oxidation properties and high temperature applications of superalloys
Abstract This review paper examined the mechanical, microstructural, corrosion properties, high temperature applications (HTAs) and protective measures that have been applied for optimal performance of superalloys. The quest for materials with excellent characteristics necessitated the development of superalloys over the years. Superalloys are class of nickel (Ni) cobalt (Co) and iron (Fe) based alloys used in jet and marine turbine engines due to their outstanding dimensional stability at a much higher temperature compared to most structural and high temperature materials. Superalloys can use a high fraction of their melting point, and this positioned them in the category of high temperature application materials. They are also reported to exhibit reasonable corrosion resistance and good mechanical properties even at elevated temperature, which facilitates their suitability for high stress manufacturing and advance applications, such as in the production of turbine engines for the marine and aerospace industries. The surface of superalloys can be protected using diffusion, overlaying and thermal barrier coatings (TBCs) which act as a barrier against oxidation, corrosion, depletion in microstructure and thermal deformation.