Effect of Ti and B additions on the microstructure and properties of FeCoCrNi high entropy alloys prepared by hot pressing

ABSTRACT

(FeCoCrNi)_100-3xTi_xB_2x (x = 0, 1, 2 and 6 at.-%) high entropy alloys (HEAs) were fabricated by hot pressing. The effects of Ti and B content on the microstructure and mechanical properties were investigated using X-ray electron diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The results show that the FeCoCrNi high-entropy alloy form single FCC phase. With the increase of Ti and B content, dual FCC phases appeared in the alloys. Additionally, the per cent elongation of alloys first increased and then declined, while the ultimate tensile strength kept moving up. The (FeCoCrNi)₉₇TiB₂ alloy has the highest per cent elongation of 13.1%, which is more than three times that of the FeCoCrNi. the (FeCoCrNi)₈₂Ti₆B₁₂ alloy shows the highest ultimate tensile strength, which is 646.5 ± 0.1 MPa. The enhanced strength is attributed to solid solution effect and Orowan process.

KEYWORDS:

• High entropy alloy
• microstructure
• ultimate tensile strength
• per cent elongation
• strengthening mechanism

Acknowledgements

This work was supported by the National Natural Science Foundation of PR China (grant number 51371098 and 51571118). National Undergraduate Training Program for Innovation and Entrepreneurship (No.201910288094Z), PR China.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [grant number 51371098, 51571118].

Notes on contributors

Yichen Zhang

Yichen Zhang is a student of College of Materials Science and Engineering, Nanjing University of Science and Technology.

Yanru Yang

Yanru Yang is a student of College of Materials Science and Engineering, Nanjing University of Science and Technology.

Jifeng Zhang

Jifeng Zhang is a student of College of Materials Science and Engineering, Nanjing University of Science and Technology.

Jiawen Li

Jiawen Li is a student of College of Materials Science and Engineering, Nanjing University of Science and Technology.

Heguo Zhu

Heguo Zhu is a professor at College of Materials Science and Engineering, Nanjing University of Science and Technology.

Zonghan Xie

Zonghan Xie is a professor at School of Engineering, Edith Cowan University.