Hexagonal Closed-Packed Precipitation Enhancement in a NbTiHfZr Refractory High-Entropy Alloy

Yueli Ma, Shiwei Wu, Yuefei Jia, Pengfei Hu, Yeqiang Bu, Xiangru Chen, Gang Wang, Jiabin Liu, Hongtao Wang, Qijie Zhai
2019 Metals  
A NbTiHfZr high-entropy alloy (HEA) with a main phase of body-centered cubic structure is fabricated. Some hexagonal closed-packed (hcp) precipitates are observed in this alloy. A thermal-mechanical process, i.e., cold-rolling followed by annealing, can manipulate the volume fraction of the hcp nano-precipitates that can enhance strength and ductility. The enhancement is tailorable as a function of the volume fraction of the hcp nano-precipitate. The results indicate that the strength-ductility
more » ... property can be manipulated via adjusting post-deformation heat-treatment methods, which provide a new strategy by utilizing metastability at high-temperature to design high strength refractory HEAs (RHEAs) without lost in ductility.
doi:10.3390/met9050485 fatcat:gcl73kzpz5d37olezefyaa54aq