About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
|
Advances in Refractory High Entropy Alloys and Ceramics
|
| Presentation Title |
Design, Synthesis, and Properties of WTaCrVHf High Entropy Alloys |
| Author(s) |
Dan J. Thoma, Caleb Hatler, Matthew Vigil, Enrique Martinez, Bochuan Sun, Saryu Fensin, Nathan Curtis, Adrien Couet, Osman El Atwani |
| On-Site Speaker (Planned) |
Dan J. Thoma |
| Abstract Scope |
Refractory high entropy alloys (RHEAs) of WTaCrVHf were investigated to develop an alloy with both higher strength and ductility as compared to pure tungsten. A computational design tool for high-throughput (HT) alloy selection used DFT and thermodynamic calculations to select single phase bcc alloys with low order-disorder transition temperatures. Directed energy deposition (DED) enabled compositionally unique HT synthesis of 25 samples per day. A dimensionless number (based upon heat and mass balances) was used for accelerated process parameter prediction. Nearly 200 different compositions were fabricated for screening of bulk samples. X-ray diffraction, hardness, and characterization allowed down-selection of alloys with at least double the strength and no cracking as compared to pure tungsten. Laser powder bed fusion (LPBF) was used for scale-up of samples with microstructural control and superior properties. Ultimately, synthesis-on-demand of any material is envisioned using this methodology to explore and down-select alloys form large compositional spaces. |