Bi2212 HTS conical tubular conductors have been prepared by the diffusion process for current lead application. The Bi2212 HTS layers are synthesized through the diffusion reaction between a Sr-Ca-Cu oxide substrate and a Bi-Cu oxide coating with Ag addition. Highly oriented HTS diffusion layers about 150μm in thickness are formed around both outside and inside of the conical tube 34/29mm in outside/inside diameter at larger end, 24/19mm in outside/inside diameter at smaller end, and 100mm in length. The transport current has been measured using two cryocoolers between 12 K at cold end and 40-70 K at warm end under 0.5 T. The transport current of 1,000 A was stably passed for 10 minutes at 50 K. The joint voltage of cold end was as low as 30μV at 50 K during 1,000 A running. The low voltage results from the low contact resistance between Bi2212 grains and Ag precipitated on the surface. Heat leakage conducted through the specimen has been newly evaluated using heat flux meter by steady-state heat flow method.
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