A particle reinforced NbTaTiV refractory high entropy alloy based composite with attractive mechanical properties.

Refractory high entropy alloys (RHEAs) are promising high temperature structural materials because of their excellent high temperature strength and high melting point. With introducing secondary particles, the high temperature mechanical properties can be further improved. However, its poor ductility limits the industrial application. In the present work, a new ductile NbTaTiV RHEA-based composite reinforced with Ti-C-O particles were in-situ synthesized through spark plasma sintering (SPS). The composite exhibits excellent room temperature compressive properties with yield strength, ultimate strength and fracture strain of 1760 MPa, 2270 MPa and 11%, respectively. A model is presented to study the strengthening mechanism, and the theoretical calculation shows that the dramatically strength enhancement is mainly due to the in-situ formation of Ti-C-O particles. • A (NbTaTiV) BCC /Ti-C-O composite was in-situ synthesized through powder metallurgy method. • The composite exhibits desirable yield strength of 1.76 GPa and ultimate strength of 2.27 GPa with reasonable fracture strain of about 11% at room temperature. • The composite also maintains an outstanding yield strength of 685 MPa at 1000 °C. • A model was present to analyze the strengthening mechanism. [ABSTRACT FROM AUTHOR]