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Round flexible cables tested last year |
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Stiffness low for packing fraction < 0.9 |
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Concern about lateral support in fixture |
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New fixture fabricated for square cable |
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0.25 x 0.25 in cable samples prepared |
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Initital testing for two samples completed |
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Data still being reduced |
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Two samples tested |
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Copper squashes to solid shape at loaded end,
appears unaffected at other end |
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Effective modulus for 70% packing fraction is
about 5E5 psi, 3% of solid copper ( 17e6 psi ) |
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Compares to earlier tests that showed modulus of
8e5 psi for 80% packing fract. |
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Are results conservative? |
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Sample seems to stick in fixture, only part of
cable is compressed |
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appled strain much higher that expected for
thermal strain (0.1 inches compression over 2 inch sample is equivalent to
about 2800C!) |
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Will cable get loose over time? |
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Strain in cable is plastic |
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Notes