|About this Abstract
||10th International Symposium on Superalloy 718 and Derivatives (2023)
||Superalloy 718 and Derivatives
||Chemical Mapping of Superalloys at the Nanoscale
||Pritesh Parikh, Darshan Jaware, Jiangtao Zhu, Karol Putyera, Rajiv S Soman
|On-Site Speaker (Planned)
Current Ni-based superalloys contain multiple alloying elements for enhanced thermal and corrosion resistance as well as improved mechanical strength at elevated operating temperatures. Segregation of alloying elements and impurities as well as formation of inclusions and precipitates because of processing conditions or during alloy life cycle can lead to decreased performance and early rupture or fracture in these alloys. A quantitative understanding of segregating/precipitant elements and the influence of microstructure on bulk mechanical properties has been carried out with TEM and APT (atom probe tomography) [1-4]. APT provides 3D chemical information that is spatially resolved at the nanoscale and high detection sensitivity up to 10 ppmw. The 3D nature of the analysis allows quantitative estimates of elemental excess over the matrix on grain boundary segregation. Further estimates on composition, size and density of inclusions and precipitates can also be computed.
In order to better understand the effect of different elements on alloy performance, we systematically study various reference standards for evidence of microstructure with a focus on quantitative analysis using APT. Both inclusions and grain boundary segregation are seen in the samples indicating the continued need for APT to understand both current and future superalloy materials. Moreover, new processing methods including additive manufacturing and nanoparticle-based alloys will require the use of APT for detailed materials characterization in superalloys.
||Definite: At-meeting proceedings