Metallurgical Abstracts on Light Metals and Alloys vol.56

Design and development of (Ti, Zr, Hf)-Al based medium entropy alloys and high entropy alloys

Takeshi Nagase*, Mitsuharu Todai**, Pan Wang***, Shi-Hai Sun**** and Takayoshi Nakano*****
* Department of Materials and Synchrotron Radiation Engineering, Graduate School of Engineering, University of Hyogo, Himeji, Hyogo, 671-2280, Japan
** Department of Environmental Materials Engineering, National Institute of Technology, Niihama College, Ehime, 792-8580, Japan
*** Singapore Institute of Manufacturing Technology, A*STAR, 637662, Singapore
**** School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China
***** Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871, Japan

[Published in Materials Chemistry and Physics, Vol. 276 (2022), pp.125-409]

https://doi.org/10.1016/j.matchemphys.2021.125409
E-mail: m.todai[at]niihama-nct.ac.jp
Key Words: high entropy alloys, alloy design, microstructure

The design and development of TiZrHfAl medium entropy alloy (MEA), and the TiZrHfAlNb_0.2 and TiZrHfAlV_0.2 high entropy alloys (HEAs) is described. The combination of 4th subgroup elements (Ti, Zr, and Hf) with Al is discussed based on the periodic table and taxonomy of HEAs. The alloys were designed using alloy parameters for HEAs, predicted ground state diagrams from the Materials Project, and the calculation of phase diagrams (CALPHAD). Rapid solidification was effective to suppress the formation of intermetallic compounds, resulting in BCC/B2 phase formation. Significant differences in the constituent phases and Vickers hardness between ingots and melt-spun ribbons were found among the TiZrHfAl MEA, TiZrHfAlNb_0.2, and TiZrHfAlV_0.2 HEAs.

Transmission electron microscopy bright field (TEM-BF) images and selected area electron diffraction (SAED) patterns of the rapidly-solidified melt-spun ribbons of examined alloys in this study.