Effect of Aging on Conductivity of Heat Resistant Overhead Line Conductors

Abstract:

Different kinds of Al and Al alloys are used for all bare overhead energy transmission lines. In the present work, the effect of heat treatments on the conductivity of Al-0.25wt.%Zr alloy has been investigated. Al-0.25wt.%Zr samples were prepared in cold graphite crucibles by using a vacuum furnace and a continuous casting line. The samples were aged isothermally and isochronally in muffle and tube furnaces. Aging was carried out at a wide range of temperatures (350-600 °C) at constant aging times (75 h, 100 h) and a wide range of aging times (25-500 h) at constant temperatures (425 °C, 450 °C). According to the experimental results, conductivities of aged samples increase up to a certain aging temperature and aging time and reach peak values, then decrease with increasing aging temperature and aging time.

• Periodical: Materials Science Forum (Volume 765)
• Pages: 783-787
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.765.783
• Online since: July 2013
• Authors: Hicran Tecer, Emine Acer, Harun Erol, Mehmet Gündüz
• Keywords: Aging, Al-Zr Alloy, Conductivity, Heat Resistant Alloy, Overhead Line Conductors

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