Prediction of mechanical properties of AlTiCrVNb high entropy alloys with B2 ordered structure

Abstract

Chemical short-range order (CSRO) is widely reported and it's certainly related to high entropy alloys (HEAs)'s mechanical properties in many different correlative researches. B2 structure ordering is usually thought to improve alloy's structural stability and strength while sacrificing the plasticity significantly. In this work, we established a B2 ordered model by the special quasi-random structure method which considering the local atomic environment (to simulate the real situation in HEAs). Depending on this model and first principles, the elements' occupancy and the B2 structure ordering are considered to explore their influence on the mechanical properties of AlTiCrVNb HEAs. The B2-type partially ordered configuration was applied to non-iso atomic ratio alloys to investigate the different influence on alloys' mechanical properties due to the changing content of Ti or Cr and the results were verified by experiment.

Keywords

• B2 order
• High entropy alloy
• First-principles
• Density functional theory
• Mechanical properties