|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Design of MoWTaTiZr Refractory Multi-principal Element Alloys
||Gaoyuan Ouyang, Prashant Singh, Jun Cui, Matthew Kramer, Duane Johnson
|On-Site Speaker (Planned)
Refractory Multi-principal Element Alloys (RMPEA) show high strength at elevated temperatures, surpassing that of Nickel-based superalloys. Recent efforts in RMPEA focus on developing lighter alloys with a combination of strength and ductility. Under the guidance of accurate density-functional theory (DFT) theory, we have studied the phase formation and room temperature (RT) elastic constant of a set of 32 compositions in the Mo-W-Ta-Ti-Zr-(Al,Cr) system. W or Cr addition increased the RT modulus and provided the basis for down selection. Down-selected RMPEA samples show good compressive yield strength (700-900MPa) and ductility (~10% strain) at room temperature. As-casted samples demonstrated good high-temperature yield strength up to 250MPa at 1300°C by small punch testing. Our results also showed that the homogenization heat treatment at ~75% of melting point is sufficient to cause phase redistribution and significant grain growth for RMPEA, adversely affecting their mechanical properties.
||High-Temperature Materials, High-Entropy Alloys, Mechanical Properties