Development and thermal stability of Cr10Mo25Ta25Ti15V25 refractory high entropy alloys

Refractory high entropy alloys (RHEAs) are promising materials for extreme environment applications, such as high-temperatures (> 1000 degrees C), corrosion and irradiation. In this study, a new CrMoTaTiV RHEA system has been designed using CALPHAD modeling and thermophysical parameter optimization, and produced by vacuum arc melting. Microstructure at room temperature as well as microstructural stability and me-chanical properties at high temperature have been investigated. It has been found that BCC alloys are formed with dendritic structures in which interdendritic regions are enriched with Ti, V and Cr, and de-pleted with Ta and Mo. Transmission electron microscopy analysis has shown dislocation tangles, loops and networks as well as the formation of nano-grains some of which are determined to be Ti-rich FCC phases. Besides, there is a secondary BCC formation below 1000 degrees C together with a Ti-rich FCC phase without any HCP or intermetallic phase formation. High strength and ductility of this alloy at the temperatures up to 1000 degrees C compared to the other RHEA systems have been attributed to its unique microstructure. This clearly shows the promise of this alloy system for high temperature applications due to its stability, high strength and possible oxidation resistance.(c) 2022 Elsevier B.V. All rights reserved.


Design of oxygen-doped TiZrHfNbTa refractory high entropy alloys with enhanced strength and ductility
Iroc, L.K.; Tukac, O.U.; Tanrisevdi, B.B.; El-Atwani, O.; Tunes, M.A.; Kalay, Yunus Eren; Aydoğan Güngör, Eda (2022-11-01)
© 2022Refractory high entropy alloys (RHEAs) are considered promising materials for high-temperature applications due to their thermal stability and high-temperature mechanical properties. However, most RHEAs have high density (>10 g/cm3) and exhibit limited ductility at low temperatures and softening at high temperatures. In this study, we show that oxygen-doping can be used as a new alloy design strategy for tailoring the mechanical behavior of the TiZrHfNbTa alloy: a novel low-density (7.98 g/cm3) ductil...
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Development and production of ductile TiZrNbHfTa refractory high entropy alloy system for extreme environments
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High entropy alloy (HEA) is a trending material class that was discovered in the early 2000s. By definition, it consists of a single or dual phase by combining 5-13 elements with a 5-35% atomic ratio. They exhibit extraordinary properties, such as structural, mechanical, corrosive and thermal. Moreover, this field gives an opportunity to combine infinite number of elements with infinite compositions. These properties and opportunities make them candidates for various extreme application areas, which will gr...
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Citation Formats
O. U. Tukac, A. Özalp, and E. Aydoğan Güngör, “Development and thermal stability of Cr10Mo25Ta25Ti15V25 refractory high entropy alloys,” JOURNAL OF ALLOYS AND COMPOUNDS, vol. 930, pp. 0–0, 2023, Accessed: 00, 2022. [Online]. Available: