|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||2023 Technical Division Student Poster Contest
||SPG-51: Experimental Observation of Heteroepitaxial Recrystallization (HeRX) outside of Low Lattice Misfit Ni-based Superalloys
||Yonguk Lee, Eitan Hershokovitz, Honggyu Kim, Eric Payton, Victoria M Miller
|On-Site Speaker (Planned)
Heteroepitaxial recrystallization (HeRX) is a promising mechanism for grain size control, but has only been reported in Ni-based superalloys with low lattice misfits that have negligible interfacial energy for epitaxial templating. In this study, HeRX is induced in LSHR—a polycrystalline Ni-based superalloy with misfit greater than the conventional limit for HeRX—and scanning TEM and EDS is performed at the γ-γ' interface of grain that had undergone HeRX. Atomic resolution STEM performed along the  zone axis reveals strong coherency across the γ-γ’ interface, demonstrating HeRX in an intermediate lattice misfit Ni-based superalloy for the first time. This finding infers that the small lattice misfit is not a strong prerequisite for the onset of HeRX, and therefore, suggests that there is a much wider range than initially believed of processing conditions under which HeRX can be used as a tool for microstructural control in Ni-based superalloys.
||High-Temperature Materials, Characterization, Other