Thermal conductivity of single and multi-stacked DI-BSCCO tapes

Abstract

We have measured the temperature dependence of the thermal conductivity, κ (T), for DI- BSCCO® tapes fabricated by Sumitomo Electric Industries, Ltd., which are (Bi,Pb)2 Sr2 Ca2 Cu3 O8 + x tapes sheathed with Ag or Ag-Au alloy. The κ (T) of the tape sheathed with Ag (residual resistance ratio (RRR) = 15) decreases with decreasing temperature and starts to increase rapidly below 60 K, with a maximum at around 15 K. On the other hand, the κ (T) of the tape sheathed with Ag-5.4 wt%Au alloy has a very low value that decreases monotonically with decreasing temperature. At around 77 K, the absolute values of κ (T) for both tapes were about 260 W m- 1 K- 1 and 80 W m- 1 K- 1, respectively. The κ (T) of a stacked sample, in which six DI-BSCCO tapes sheathed with Ag are soldered, was also measured. The measured κ (T) was fairly well reproduced by the estimated κ (T), which was calculated using the measured κ (T) of the single tape and solder. © 2009 Elsevier Ltd. All rights reserved.