|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||Localized Phase Transformation at Stacking Faults and Mechanism-based Alloy Design
||Longsheng Feng, Timothy Smith, Ashton Egan, Fan Zhang, Michael J. Mills, Yunzhi Wang
|On-Site Speaker (Planned)
A new phenomenon was observed in some Ni-based superalloys where phase transformations occur at and are confined to stacking faults, which we refer to as localized phase transformations (LPTs). Alloys with different types of LPTs such as ordering and disordering are found to have drastically different creep properties. It is thus of great importance to understand the underlying physics behind this localized phase transformation. A thermodynamic model is proposed to understand the foundation of LPT and to address fundamental questions why LPT occurs, why LPT is confined at stacking faults, what types of LPT are expected at stacking faults and how LPT impacts mechanical properties. The proposed LPT mechanism is used to establish a new design strategy for the next-generation LPT-strengthened superalloys. This work is supported by NSF under DMREF program.