Development and optimization of operating characteristics of cryogenic materials |
Conducting highly-pures aluminum fibres are placed into the matrix of high-strength Al alloy, which is suitable for their joint working and operation. This fabrication technology allows a reliable electrical and thermal contact of a matrix and a conductor. During the fabrication of the multi-fibre conductor, in each of tubes of Al alloy, rods of pure aluminum with R300K/R4.2K ~ 10000 are introduced. After that the ingots are placed in a tube with a diameter of 35 mm from the similar Al alloy. The combined billet undergoes radial pressing at Т =180oС. On the final stage the composite material obtains a form of flat busbar with a rectangular cross-section, and with that the scheme of current-carrying fibres, surrounded by the strengthening matrix, is not violated. The R300K/R4.2K value of the busbar equals to 2700-800 in the helium-neon temperature range (4.2-28 К). The magnetoresistance value does not exceed the range 5-7 in magnetic fields up 15 T.
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