J. Mater. Sci. Technol. ›› 2018, Vol. 34 ›› Issue (2): 349-354.DOI: 10.1016/j.jmst.2017.07.013

Special Issue: Titanium Alloys 2018 Stainless Steel & High Strength Steel 2018

• Orginal Article • Previous Articles     Next Articles

Effect of lattice distortion on solid solution strengthening of BCC high-entropy alloys

Zhipeng Wanga, Qihong Fanga(), Jia Lia, Bin Liub, Yong Liub()   

  1. aState Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Hunan University, Changsha 410082, China
    bState Key Laboratory for Powder Metallurgy, Central South University, Changsha 410083, China
  • Received:2017-05-03 Revised:2017-06-12 Accepted:2017-07-07 Online:2018-02-10 Published:2018-02-10

Abstract:

:An analytical model is established to study the influence of lattice distortion and fraction of Hf on the yield strength of the BCC TiNbTaZrHfx multi-component high entropy alloys (HEAs). Meanwhile, the mechanism of solid solution strengthening caused by lattice distortion is also discussed in the HEA. The distorted unit cell is introduced to indicate the lattice distortion effects induced by the differences of the atomic size and shear modulus by doping other elements in Ti-based metal. The results show that the calculated values of the alloying yield strength considering the path of least resistance are obtained with regard to various grain sizes for the equiatomic TiNbTaZrHf HEA, which is well in line with the experimental results. Furthermore, it is predicted that the alloying yield strength is the largest value in the case of the same grain size for the Hf atomic fraction of 0.122. The meaningful modeling could provide a theoretical method to investigate the yield strength and alloying design of other BCC HEAs in the future.