Study on Microstructure and Crystal Structure of(Ti1/4Zr1/4V1/4Nb1/4)Alx High Entropy Intermetallic Compounds
Five principal-element(Ti1/4Zr1/4V1/4Nb1/4)Alx high-entropy intermetallic compounds were designed and prepared by vacuum arc melting method.The changes in crystal structures,microstructures and hardnesses of as-cast and high-temperature annealed alloys were investigated in detail.The results indicated that the(Ti1/4Zr1/4V1/4Nb1/4)Alx high entropy intermetallic compounds were based on ordered D022 structure with a small amount of L10 precipitates.The alloys'microstructure was a dendritic structure.Because of the different distribution of elements in dendritic and interdendritic regions,phase separation phenomenon occurs in the alloys.The(Ti1/4Zr1/4V1/4Nb1/4)Al3.5 alloy had the least content of L10 phase,which basically disappeared after heat treatment at 1 300 ℃.This alloy could still maintain its as-cast matrix structure at a high temperature up to 1 400 ℃ without precipitation of other phases,indicating that it had excellent high-temperature thermal stability.
high entropy alloyintermetallic compoundsheat treatmentmicrostructurecrystal structure