A thermally adaptive insulation has previously been developed by the US Army. The insulation is designed to expand at lower temperatures and shrink at higher temperatures. This is accomplished using multi-component polymer fibers that are spun in a side-by-side configuration that change curvature in response to a temperature change. The concept is based on Timoshenko’s bi-metallic beam bending theory. In this work, a method for measuring curvature change of individual fibers over a range of temperatures was developed. Determining the curvature change of fibers is a necessary step in optimizing performance of the insulation as a whole. Curvature change is induced by suspending fibers on the surface of a cooling bath and changing the temperature. Taking digital images at discrete temperature intervals using a microscope and then extracting fiber curvature from the images provides a consistent method for determining curvature change.
Journal: TechConnect Briefs
Volume: TechConnect Briefs 2019
Published: June 17, 2019
Pages: 5 - 8
Industry sector: Advanced Materials & Manufacturing
Topics: Advanced Materials for Engineering Applications, Materials Characterization & Imaging