High-temperature tribological behavior of CoCrFeNiV high-entropy alloys: A parallel comparison with CoCrFeNiMn high-entropy alloys

The present work investigates the high-temperature tribological behavior of CoCrFeNiV fabricated by vacuum hot pressing sintering, and parallel experiments were conducted with CoCrFeNiMn as a comparison. It was found that the wear rate of CoCrFeNiV is almost an order of magnitude lower than for CoCrFeNiMn. Compared with CoCrFeNiMn of a single FCC, the precipitation of the hard sigma (sigma) phase from the addition of V element made CoCrFeNiV possess excellent hardness (975 +/- 11 HV) and high-temperature wear-resistance. The detailed characterization of the worn surface revealed that mild adhesion and oxidative wear are the dominant wear mechanisms of CoCrFeNiV. With the increase of temperature, the tribo-oxidation composed of V2O5, NiO and Cr2O3 play an excellent anti-oxidation lubrication role during the friction process. The higher volume fraction of the hard a phase and the dense oxide glaze layer resulted in wear of approximately 0.289 x 10(-4) mm(3)/Nm at 800 degrees C.

Automated summary

This study investigates the high-temperature tribological behavior of CoCrFeNiV and compares it with CoCrFeNiMn. The addition of V element in CoCrFeNiV leads to a significant reduction in wear rate and an increase in hardness. The worn surface analysis reveals that mild adhesion and oxidative wear are the dominant wear mechanisms of CoCrFeNiV. The presence of V2O5, NiO, and Cr2O3 provides excellent anti-oxidation lubrication during the friction process.