About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
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Symposium
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Additive Manufacturing Modeling and Simulation: Microstructure, Mechanics, and Process
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Presentation Title |
Now On-Demand Only - Influence of Microstructure on Fatigue Crack Growth: An Combined Experiment and Model Investigation in EBM Nickel-Based Supper Alloy Haynes 282 |
Author(s) |
Jiahao Cheng, Patxi Fernandez-Zelaia, Sebastien Dryepondt, Xiaohua Hu, Michael Kirka |
On-Site Speaker (Planned) |
Jiahao Cheng |
Abstract Scope |
With ORNL’s recent advancement in powder-bed fusion-based additive manufacturing technique, printing of Nickel-based superalloy with accurate site-specific control of grain orientation and morphology at microscale is enabled. This creates the possibility of microstructure-design for improved material properties and service life. This research focuses on Haynes 282, an γ' precipitation-strengthened nickel-based superalloy known for its exceptional high-temperature creep resistance and fabricability and used for advanced ultrasupercritical (A-USC) steam turbines. Fatigue cracking is the dominating failure in such components, thus understanding and improving fatigue crack resistance through microstructure optimization is imperative. In this study, a Hayne 282 specimen with ‘composite’ microstructure (i.e. different regions of the specimen have distinct microstructures) was fabricated and controlled experiment of fatigue crack growth in the ‘composite’ microstructure was conducted. The results showed higher crack growth rate in coarse columnar grain region than in fine equiaxed grain region, which is analyzed with crystal plasticity finite element modeling. |