Investigation of Cold Sprayed MCrAlY as a Bondcoat Candidate for Thermal Barrier Coating

As an emerging technique, cold gas dynamic spray is one of the latest tools for dimensional repair and coating applications. One of critical coating applications is thermal barrier coatings (TBC) for high efficiency turbine engine components. Many studies revealed that oxidation behavior and formation of thermally grown oxide (TGO) on MCrAlY bondcoat plays a paramount role in failure modes and lifetimes of TBCs. In this work, we will investigate the feasibility of cold sprayed MCrAlY as a bondcoat candidate for TBC by comparing with those deposited by thermal (APS and HVOF) spray. The characterization of coatings were performed on test specimens fabricated by cold spray (CS), air plasma spray (APS) or high velocity oxygen fuel spray (HVOF). The characterization and anlyses include microstructures, morphologies, roughness and TGO layer and growth kinetics. Test results exhibit a potential of cold spray process for the improvement of engineered TBCs.