The thermal expansion of a Kevlar® 49 cord down to cryogenic temperatures

In this work the thermal expansion of a twisted Kevlar® 49 cord assembly made at SRON in the 293 K to 7 K temperature range is presented. In addition to these results, the setup used to measure this thermal expansion is described, as are the methods used to calibrate and verify the accuracy of this setup. The setup is accurate to within ±5 % compared to Ti-6Al-4V literature values. The thermal expansion of the SRON Kevlar® 49 cord assembly is measured and compared to the sparse literature available. At 7 K, the total fractional expansion of the Kevlar® cord assembly is 16E-4 relative to 293 K.