Microstructure manipulation by laser-surface remelting of a full-Heusler compound to enhance thermoelectric properties
Autor: | Ralf Heiderhoff, Leonie Gomell, Tobias Haeger, Moritz Roscher, Christina Scheu, Hanna Bishara, Baptiste Gault, Thomas Riedl |
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Rok vydání: | 2022 |
Předmět: |
Materials science
Polymers and Plastics Scanning electron microscope 02 engineering and technology Scanning thermal microscopy Atom probe engineering.material 01 natural sciences law.invention Thermal conductivity law 0103 physical sciences Thermoelectric effect 010302 applied physics Quenching business.industry Metals and Alloys 021001 nanoscience & nanotechnology Microstructure Heusler compound Electronic Optical and Magnetic Materials Ceramics and Composites engineering Optoelectronics 0210 nano-technology business |
Zdroj: | Acta Materialia. 223:117501 |
ISSN: | 1359-6454 |
Popis: | There is an increasing reckoning that the thermoelectric performance of a material is dependent on its microstructure. However, the microstructure-properties relationship often remains elusive, in part due to the complexity of the hierarchy and scales of features that influence transport properties. Here, we focus on the Heusler-Fe2VAl compound, which shows promising thermoelectric properties, is non-toxic, cheap, and consist of earth-abundant elements. We directly correlate microstructure and local properties, using advanced scanning electron microscopy methods including in-situ four-point-probe technique for electron transport measurements. The local thermal conductivity is investigated by scanning thermal microscopy. Finally, atom probe tomography provides near-atomic scale compositional analysis. To locally manipulate the microstructure, we use laser surface remelting. The rapid quenching creates a complex microstructure with a high density of dislocations and small, elongated grains. We hence showcase that laser surface remelting can be employed to manipulate the microstructure to reduce the thermal conductivity and electrical resistivity, leading to a demonstrated enhancement of the thermoelectric performance at room temperature. |
Databáze: | OpenAIRE |
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