Karati, A and Mishra, SR and Ghosh, S and Mallik, RC and Shabadi, R and Ramanujan, RV and Yadav, SK and Murty, BS and Varadaraju, UV (2022) Thermoelectric properties of a high entropy half-Heusler alloy processed by a fast powder metallurgy route. In: Journal of Alloys and Compounds, 924 .
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Abstract
A half-Heusler (HH) type high entropy alloy (HEA) Ti2NiCoSnSb has been synthesized by a fast powder metallurgy route for the first time. Mechanical alloying (MA) by wet milling produced a powder with a minor fraction of the HH phase. The dry milling route resulted in the desired single-phase HH material. Consolidation of the nanocrystalline mechanically alloyed (MA) powder by spark plasma sintering (SPS) resulted in a majority HH phase. Interestingly, the nanocrystalline alloy exhibited simultaneous enhancement in the Seebeck coefficient and electrical conductivity, with a maximum ZT of 0.13 at 973 K observed for the dry milled alloy. The band structure obtained by density functional theory (DFT) was in good agreement with the ultraviolet-visible-near infrared (UV-Vis-NIR) absorption spectroscopy results. The DFT calculations and microstructural analysis suggest that phase separation strongly influenced the thermoelectric properties. The band structure calculations provided a good rationale for the phase evolution and thermoelectric properties.
Item Type: | Journal Article |
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Publication: | Journal of Alloys and Compounds |
Publisher: | Elsevier Ltd |
Additional Information: | The copyright for this article belongs to the Elsevier Ltd. |
Keywords: | Electronic band structure; Half-Heusler; High entropy alloy; Mechanical alloying; Thermoelectric material |
Department/Centre: | Division of Physical & Mathematical Sciences > Physics |
Date Deposited: | 03 Sep 2022 05:05 |
Last Modified: | 03 Sep 2022 05:05 |
URI: | https://eprints.iisc.ac.in/id/eprint/76401 |
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