About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
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Presentation Title |
Dwell Fatigue Behavior of a Fine-grain Ni-based Superalloy 718 at High Temperature: From Strain Localization to Crack Initiation |
Author(s) |
Melanie Bordas-Czaplicki, Damien Texier, Jonathan Cormier, Patrick Villechaise, Vincent Roué |
On-Site Speaker (Planned) |
Melanie Bordas-Czaplicki |
Abstract Scope |
Previous work on dwell fatigue of Alloy 718 has shown that crack initiation mechanisms are driven by the interaction of intergranular oxidation and the cumulated plastic strain. The aim of this study is to characterize the strain localization at grain boundaries leading to crack initiation. High resolution-digital image correlation (HR-DIC) tests complemented with EBSD characterization were performed in order to understand grain boundary sliding activity during dwell-fatigue tests at 610°C and 1s or 10s hold time. Tests were performed in vacuum and interrupted at the same cumulated plastic strain thanks to real-time macroscopic DIC measurements. The results allow to determine grains boundaries sensitive to preferential oxidation. Finally, the goal of this study was to combine tests with prior oxidation and to determine the interactions between grain boundary strain localization and grain boundary oxidation in dwell fatigue leading to crack initiation. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Temperature Materials, Other, Other |