• Title/Summary/Keyword: Cu Powder

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Thermoelectric Properties in the Cu Doping Effects of the n-type Bi-Te Powders (Bi-Te계 n형 열전분말의 열전특성에 미치는 Cu 도핑의 영향)

  • Park, Min Soo;Koo, Hye Young;Ha, Gook Hyun;Park, Yong Ho
    • Journal of Powder Materials
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    • v.22 no.4
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    • pp.254-259
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    • 2015

  • $Bi_2Te_3$ related compounds show the best thermoelectric properties at room temperature. However, n-type $Bi_2Te_{2.7}Se_{0.3}$ showed no improvement on ZT values. To improve the thermolectric propterties of n-type $Bi_2Te_{2.7}Se_{0.3}$, this research has Cu-doped n-type powder. This study focused on effects of Cu-doping method on the thermoelectric properties of n-type materials, and evaluated the comparison between the Cu chemical and mechanical doping. The synthesized powder was manufactured by the spark plasma sintering(SPS). The thermoelectric properties of the sintered body were evaluated by measuring their Seebeck coefficient, electrical resistivity, thermal conductivity, and hall coefficient. An introduction of a small amount of Cu reduced the thermal conductivity and improved the electrical properties with Seebeck coefficient. The authors provided the optimal concentration of $Cu_{0.1}Bi_{1.99}Se_{0.3}Te_{2.7}$. A figure of merit (ZT) value of 1.22 was obtained for $Cu_{0.1}Bi_{1.9}Se_{0.3}Te_{2.7}$ at 373K by Cu chemical doping, which was obviously higher than those of $Cu_{0.1}Bi_{1.9}Se_{0.3}Te_{2.7}$ at 373K by Cu mechanical doping (ZT=0.56) and Cu-free $Bi_2Se_{0.3}Te_{2.7}$ (ZT=0.51).

  • https://doi.org/10.4150/KPMI.2015.22.4.254 인용 PDF KSCI

The Effect of Powder Characteristics on the Permeability of Copper Powder Wicks in Heat Pipe Applications

  • Lin, Yueh-Ju;Hwang, Kuen-Shyang
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.318-319
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    • 2006

  • The thermal dissipation performance of sintered heat pipes is usually determined by the capillarity and permeability of the Cu powder wicks. Since the capillary provided by the Cu powder is usually large enough to draw water from the condenser end to the evaporator end, the permeability has become the controlling factor. In this study, Cu powders with different particle sizes and shapes were loosely sintered, and their permeabilities were compared. The results show that more complicated shapes, finer particle sizes, lower porosities, and rougher pore surfaces give lower permeability and thermal dissipation.

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