|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||High Entropy Alloys VI
||Designing Ti-Zr-Ta-Mo-W Refractory High-entropy Alloy
||Aayush Sharma, Prashant Singh, Mouhamad S. Diallo, Pratik Ray, Ganesh Balasubramanian, Matthew J. Kramer, Duane D. Johnson
|On-Site Speaker (Planned)
Refractory-based high-entropy alloys containing Molybdenum (Mo) are known for their high-temperature strength and superior corrosion resistance. Focusing on Ti-Zr-Ta-Mo-W, we use density functional theory to investigate phase stability, electronic-structure, and ordering properties, including atomic short-range order, over composition space to identify more stable systems. We use Green's function KKR combined with the coherent-potential approximation (CPA) for relative stability and tuning ordering and mechanical properties, and KKR-CPA-based thermodynamic linear-response to predict short-range order. We model the deformation characteristics with atomistic molecular dynamic simulations, with potentials verified from our first-principles data. We find that alloy stability and mechanical properties are sensitive to composition; in particular, we predict MoW-rich regions of improved stability with dramatically enhanced (factor of ~3) Young's modulus over equiatomic alloys. The predicted results are validated against our nanoindentation results, which motivate application of the alloy as an ideal candidate for high-temperature structural applications.
||Planned: Supplemental Proceedings volume