About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
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Presentation Title |
On Fatigue Crack Initiation with Fine Granular Area in Metal Matrix without Defect during Very High Cycle Fatigue |
Author(s) |
Guocai Chai |
On-Site Speaker (Planned) |
Guocai Chai |
Abstract Scope |
During very high cycle fatigue (VHCF) of high strength steels, fatigue crack initiation at a subsurface inclusion with a fine granular area (FGA) is a typical phenomenon. Local stress or strain concentration at subsurface inclusion is a critical factor. Fatigue crack initiation with an FGA in bulk matrix has rarely been reported. In this paper, a fundamental study on formation of FGA in bulk matrix of an austenitic stainless steel has been done using a novel one single specimen progressive stepwise-load increasing test (PSLIT). With this method, FGA has been observed in the subsurface bulk matrix. With electron microscopy techniques, damage and crack initiation behaviours in the material have been studied. Strain localization and grain fragmentation are the main processes for the formation of FGA. Local plasticity exhaustion leads to crack initiation due to local stress concentration. This method can also be used to predict damage rate in individual specimen. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Iron and Steel, Characterization |