About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
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Symposium
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Deformation and Damage Mechanisms of High Temperature Alloys
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Presentation Title |
Microstructural and Mechanical Aspects of Damage Mechanisms In Dwell-fatigue In Inconel 718 |
Author(s) |
Melanie Bordas-Czaplicki, Jonathan Cormier, Patrick Villechaise, Vincent Roue |
On-Site Speaker (Planned) |
Melanie Bordas-Czaplicki |
Abstract Scope |
Damage mechanisms in dwell-fatigue applied to DA718 Inconel alloy has been investigated. All tests were carried out at 650 °C, in stress-controlled mode, trapezoidal waveform at Rσ=0.05 and hold times between 1s and 90s. Damage in dwell-fatigue originates from oxidation, fatigue and creep. The increase in dwell-time at maximum stress leads to a transition from fatigue-dominated to creep dominated damage, overall reducing the cyclic life and increasing the plastic strain rate. All crack initiations were at surface or sub-surface particles, especially at carbides/nitrides. In order to understand damage mechanisms and implication of each phenomenon, interrupted tests were introduced. It has been possible to find a consistency between a transitional cumulative plastic strain, obtained around minimum strain rate, and damage mechanisms. |
Proceedings Inclusion? |
Planned: |