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Title: Laser additive manufacturing of powdered bismuth telluride
Traditional manufacturing methods restrict the expansion of thermoelectric technology. Here, we demonstrate a new manufacturing approach for thermoelectric materials. Selective laser melting, an additive manufacturing technique, is performed on loose thermoelectric powders for the first time. Layer-by-layer construction is realized with bismuth telluride, Bi 2 Te 3 , and an 88% relative density was achieved. Scanning electron microscopy results suggest good fusion between each layer although multiple pores exist within the melted region. X-ray diffraction results confirm that the Bi 2 Te 3 crystal structure is preserved after laser melting. Temperature-dependent absolute Seebeck coefficient, electrical conductivity, specific heat, thermal diffusivity, thermal conductivity, and dimensionless thermoelectric figure of merit ZT are characterized up to 500 °C, and the bulk thermoelectric material produced by this technique has comparable thermoelectric and electrical properties to those fabricated from traditional methods. The method shown here may be applicable to other thermoelectric materials and offers a novel manufacturing approach for thermoelectric devices.
Authors:
; ; ;
Award ID(s):
1748188
Publication Date:
NSF-PAR ID:
10090276
Journal Name:
Journal of Materials Research
Volume:
33
Issue:
23
Page Range or eLocation-ID:
4031 to 4039
ISSN:
0884-2914
Sponsoring Org:
National Science Foundation
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