Effects of hot pressing temperature on microstructure, hardness and corrosion resistance of Al₂NbTi₃V₂Zr high-entropy alloy

Abstract

A novel lightweight high-entropy alloy Al₂NbTi₃V₂Zr was fabricated by vacuum hot pressing. The effects of sintering temperature (1200–1550°C) on the microstructure, hardness and corrosion resistance of the alloy were investigated. Results showed that Al₂NbTi₃V₂Zr mainly consisted of simple cubic matrix and (Zr, Al)-based intermetallic phase (α-phase) at sintering temperatures of 1200–1350°C. Moreover, the matrix phase transformed from simple cubic to body-centred cubic phase, and (Ti, Zr, Al)-based intermetallic precipitated from the matrix at temperature of 1450°C. The fabricated Al₂NbTi₃V₂Zr alloy had low density of 5.05–5.23 g cm^–3, high hardness of 510–728 HV and excellent corrosion resistance in 10 wt-% HNO₃ solution.

Keywords:

• Al₂NbTi₃V₂Zr high-entropy alloy
• Sintering temperature
• Microstructure
• Hardness
• Corrosion resistance

Acknowledgements

The authors would like to thank TianFu Song for help with the SEM, Xing Hu for the specimen preparation and Yingjiu Zhang for help with electrochemical corrosion experiments.