About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
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Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
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Presentation Title |
Influence of Compressive Hold Times In Dwell-fatigue of Alloy 718 |
Author(s) |
Melanie Bordas-Czaplicki, Jonathan Cormier, Patrick Villechaise, Vincent Roue |
On-Site Speaker (Planned) |
Melanie Bordas-Czaplicki |
Abstract Scope |
The impact of hold times in tension and/or compression has been investigated in DA718 Inconel alloy. All tests were carried out at 650 °C, in stress-controlled mode, trapezoidal waveform at Rσ=-1 and 10 s hold times at maximum and/or minimum stress. Compared to pure tensile dwell-fatigue tests, compression drastically reduced the fatigue life and alloy’s ductility independently of the tension hold time. The evolution of maximum and minimum of plastic strain followed the same trend for each condition. Crack initiation from surface non-metallic particles and mixed micro-propagation has been systematically observed. Damage mechanisms were studied through interrupted tests by following crack initiation on the gauge length thanks to a SEM. Initiation at particles appeared at the first cycles for each waveform. It has been observed an interaction between environment and delta phase at grain boundaries followed by crack initiation. |
Proceedings Inclusion? |
Planned: |