| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Microstructural Templates Consisting of Isostructural Ordered Precipitate / Disordered Matrix Combinations: Microstructural Evolution and Properties
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| Presentation Title |
Investigation of Nucleation Mechanisms Associated with the Formation of Coprecipitates in Ni-based Superalloys |
| Author(s) |
Hariharan Sriram, Semanti Mukhopadhyay, Michael Mills, Yunzhi Wang |
| On-Site Speaker (Planned) |
Hariharan Sriram |
| Abstract Scope |
Experimental studies have shown a wide variety of γ'/γ” coprecipitates in IN718-based alloys. Although the coprecipitate's growth and coarsening mechanisms have been investigated, the heterogeneous nucleation mechanisms of γ” on existing γ' that lead to different types of coprecipitates are yet to be understood. We analyze the individual and combined effects of concentration field and coherency elastic stress field associated with existing γ' at different sizes on nucleation of γ". The chemical driving force for nucleation is calculated using the CALPHAD databases, while the contributions from elastic interaction and anisotropic interfacial energies between different interfaces are quantified by comparing results from phase-field simulation and experimental characterization. Subsequently, an explicit nucleation algorithm is used in phase-field simulations to study nucleation and early stage of growth. Furthermore, insights gained from the analysis will be used as inputs in fast-acting precipitation models to design heat treatments for the coprecipitate alloys. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Modeling and Simulation, Phase Transformations, High-Temperature Materials |