On the application of NbTaTiVW refractory high entropy alloy particles in the manufacturing process of WC based matrix body drill bits

Abstract

In this study, NbTaTiVW refractory high entropy alloy (RHEA) particles were used as a modulator to tailor mechanical performance and wear resistance of WC based matrix body drill bits. A series of (WC)100(NbTaTiVW)100-x (x = 0, 12, 20, 30 wt%) loose powder compacts was spontaneously infiltrated by Cu-Ni-Sn alloy binder under argon atmosphere. Microstructural studies indicated an adequate infiltration of WC/NbTaTiVW reinforcement phases with Cu-alloy binder without any micro or macro porosities. No intermetallic phases could be revealed at the WC/NbTaTiVW/binder interfaces owing to the high thermal stability of the reinforcement phases. The Charpy impact energy of the composites increased with increasing the content of RHEA particles, while the wear resistance was highly retained. The WC-20 wt% NbTaTiVW infiltrated composite exhibited 200% increase in the impact energy with only 10% increase in the wear rate. The analysis of fracture surface indicated that all the composites fail from cracks initiation and propagation in the WC particles. Finally, RHEA particles were introduced as proper and highly stable reinforcement particles for modulating mechanical properties of the WC-based matrix body drill bits.