Additive manufacturing, or 3D Printing, offers tremendous opportunity for efficient, custom manufacturing of critical parts. This processing approach can be applied to Nickel-based superalloys, which are specialized materials that have excellent high-temperature strength and good oxidation resistance, and hence are used in a wide range of technologies and applications. This award supports research to understand the fundamental relationships between processing and performance which will allow development of optimal additive manufacturing processes to fabricate nickel-based superalloy parts. An optimal process will enable the additively manufactured nickel-based superalloys to have excellent resistance to surface damage by high temperature oxidation while also retaining superior strength. Additively manufactured alloys have potential application in aerospace, automotive, biomedical, energy, and chemical industries. The results from this research therefore have the potential to benefit the U.S. economy and enhance manufacturing capabilities. Moreover, the research results will be incorporated into curriculum enhancement, student training, industrial collaboration, and an educational outreach program. Activities supported under this award will contribute to recruiting students from underrepresented groups to participate in research, and will positively impact higher education in science and engineering disciplines.
The combination of high strength and superior oxidation resistance of nickel-based superalloys make these materials good candidates for high-temperature applications. Additively manufactured nickel-based superalloys can possess mechanical properties comparable to those produced by conventional manufacturing techniques, but their resistance to high temperature oxidation is not comparable to conventionally manufactured components. To enable the application of additive manufacturing for high-temperature alloy fabrication, this research aims to understand and predict the processing-microstructure-oxidation relationships for additive manufactured nickel-based superalloys. The research team will fabricate nickel-based superalloys in layered forms using the laser engineered net shaping additive manufacturing technique, perform microstructural analysis on the alloys using electron microscopy, predict the solidification microstructure of the additive manufactured Ni alloys using numerical modeling techniques, and measure the high-temperature oxidation performance of additive manufactured Ni alloys via thermogravimetric analysis. This research will provide knowledge for determination of a critical cooling rate below which the superior high-temperature corrosion properties can be maintained in the additive manufactured nickel-based superalloys.
