About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Additive Manufacturing Fatigue and Fracture: Effects of Surface Roughness, Residual Stress, and Environment
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Presentation Title |
Fatigue Crack Growth of Laser Powder Bed Fusion Produced Alloy 718 at Room and Elevated Temperatures |
Author(s) |
Jamie J. Kruzic, Halsey Ostergaard |
On-Site Speaker (Planned) |
Jamie J. Kruzic |
Abstract Scope |
Laser powder bed fusion (LPBF) produces unique microstructures (e.g., columnar grains, crystallographic texture, etc.) that influence the mechanical properties of alloys. In this work, the fatigue crack growth properties of LPBF produced alloy 718 were examined for two orthogonal cracking orientations relative to the build direction. Two post heat treatments were used: solution plus duplex ageing both with and without prior hot isostatic pressing (HIP). HIP was found to recrystallize much of the columnar microstructure, remove residual stresses, and mostly eliminate the weak anisotropy observed in the room temperature fatigue crack growth behavior for the non-HIP material. Post-HIP, room temperature fatigue thresholds reached values reported for wrought 718. At 650˚C, anisotropy in fatigue crack growth rates became significant and LPBF 718 performed better than wrought 718. Microstructure and residual stress analysis, fractography, and crack profiles were used to further understand the microstructure influence on the fatigue crack growth properties. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, High-Temperature Materials, Mechanical Properties |