| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
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| Presentation Title |
Local Phase Transformation at Microtwins and Planar Defects in Creep Deformed Ni-Base Superalloys |
| Author(s) |
Ashton J. Egan, Fei Xue, Longsheng Feng, Shakthipriya Baskar Kannan, Gregory Sparks, Timothy Smith, Emmanuelle Marquis, Yunzhi Wang, Maryam Ghazisaeidi, Michael Mills |
| On-Site Speaker (Planned) |
Ashton J. Egan |
| Abstract Scope |
In the intermediate temperature creep regime of Ni-based superalloys (~700 °C) deformation is dominated by thermal activation of planar defects and microtwinning, where diffusion mediated reordering and segregation of key elements play a major role in controlling strain rate. Of particular interest are alloys with Local Phase Transformation (LPT) strengthening, a dynamic process whereby phases form along defects. During this study the strengthening effects of several alloys, including specifically oriented single crystal NA1 and ME501, in the LPT composition regime are explored to elucidate atomic scale processes. Advanced characterization of active deformation mechanisms and LPT was accomplished using probe corrected Scanning Transmission Electron Microscopy (STEM), atomic scale Energy Dispersive X-Ray Spectroscopy (EDS), TEM-correlated Atom Probe Tomography (APT), and multislice STEM modeling. Mesoscale characterization utilizing Scanning Electron Microscopy (SEM) based Controlled Electron Channeling Contrast Imaging (cECCI) support atomic scale analyses. Understanding LPT effects inform both multiscale modeling efforts and alloy development. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, High-Temperature Materials, Phase Transformations |