Mechanical and Electrical Testing of Composite Aluminum Cryoconductors
Results are reported of monotonic and cyclic-strain resistivity experiments at 4.2 and 20 K on Alcoa fabricated composite aluminum cryoconductors. The conductors contain filaments of nominal 99.999% pure aluminum in an Al-Fe-Ce matrix. Initial conductor resistance ratios (RR = R(273 K)/R(T)) range from 340 to 800 at 4.2 K and from 259 to 500 at 20 K. Sample resistivity increases nearly linearly with monotonie plastic strain at a rate of 7 ± 2 nΩcm / % strain. Force controlled cyclic loadings cause the resistivity to increase rapidly to a saturation value reached after about 500 cycles.
KeywordsFatigue Helium Resis Posite Boulder
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