Measurements of the Dynamic Complex Young's and Shear Moduli ofChlorotrifluoroethylene (Kel-F) (Trademark) Using a Resonant Bar Technique

摘要

The material Kel-F is a candidate for use as a mechanical transducer inapplications requiring small volume, lightweight sensors. However, there is concern that the temperature dependence of its elastic moduli will result in an unacceptable temperature-dependent sensitivity in some configurations. In this investigation, a cylindrical bar of Kel-F was selectively excited in its lowest flexural, torsional, and longitudinal modes in order to determine the material elastic properties and to make an estimate of their temperature dependence. A free-free bar was excited electrodynamically and from these resonant modes both the Young's and shear elastic moduli were determined. The complex modulus can be found by measuring the quality factor (Q) for each resonant mode. It was concluded that from 0 to 24 degrees C, the Young's modulus varied less than 1.6 dB and the shear modulus less than 2.0 dB. The measurements were taken by Code 421 in the materials laboratory at the New London Detachment of the Naval Undersea Warfare Center, Division Newport. Kel-F, Elastic properties, Interferometric sensor, Material properties mechanical transducer, Resonant bar, Shear modulus, Young's modulus.