Alloying effect on the mechanical and microstructural properties of RHEAs based on the system MoNbTaWV

Authors:

Ribeiro, Bernardo L.(1,2); Santos, Rúben F. (1,2,3); Barbosa, Maria (2); Sequeiros, Elsa W.(1,2)

1- LAETA/INEGI – Institute of Science and Innovation in Mechanical and Industrial Engineering, Portugal

2- Departamento de Engenharia Metalúrgica e de Materiais da Faculdade de Engenharia da Universidade do Porto, Portugal

3- CCF – Centro de Competências Ferroviário, Portugal

Abstract:

In recent years, High Entropy Refractory Alloys (RHEAs) have been presented as possible alternatives to the state-of-art Ni-based superalloys, due to an outstanding combination of properties under high-temperature service conditions. The MoNbTaW system has been particularly explored due to its considerable high yield strength at temperatures around 1200 °C. Yet, these alloys present a brittle behaviour at room temperature, narrowing their applications. To improve the MoNbTaW properties, in-situ alloying with additions of Vanadium (V) by Direct Energy Deposition (DED) assisted by thermodynamical simulations (CALPHAD) has been explored to accelerate the screening of promising compositions. In this contribution, we present the room temperature microstructural and mechanical characterisation to evaluate the influence of V on the MoNbTaW system.

DOI:

https://doi.org/10.59499/EP235765551