There has been a need for suitable coatings to provide protection for a sufficient length of time to match the outstanding high temperature strength capabilities of Mechanically Alloyed (MA) ODS superalloys. The quest for such coatings has instigated many research studies. The findings reported here evolved from studies on substrate composition effects and coating application types and structures that are necessary in order to develop viable substrate-coating systems. The systems were evaluated using cyclic and isothermal oxidation tests and Burner Rig hot corrosion (sulfidation) tests. The results indicate, inter alia, beneficial substrate compositional effects from Al in high Al/γ′ phase superalloys. Compatible overlay coatings of, for example, NiCoCrAlY(Ta) for INCONEL* alloy MA 6000 and advanced industrial ODS superalloys, such as INCONEL alloy MA 760, were identified that are commercially available. These conclusions are supported by initial results from a much broader coatability program currently in progress. This program also includes several combinations of duplex coatings, utilizing a compatible inter-layer coating, that have enhanced both coatability and corrosion resistance performance of these Ni-based ODS superalloys.

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