Accession Number : ADA623246


Title :   Methods of Measuring Stress Relaxation in Composite Tape Springs


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INSTITUTE OF TECHNOLOGY WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT


Personal Author(s) : Heppe, Justin T


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA623246


Report Date : 26 Mar 2015


Pagination or Media Count : 104


Abstract : Composite tape springs present an opportunity to use stored energy for the deployment of space structures. Concern has risen over the dissipation of strain energy during storage due to viscoelasticity inherent in polymeric materials commonly used as the composite matrix. Tests to measure the internal behavior of a composite tape spring over time are conducted along with methods of analyzing and fitting the resulting data. The three constant strain configurations tested were compression force of the cross section, a restraining force of a longitudinal fold, and the change in shape of a folded section. While the shape changing test did not appear to be sensitive enough, the stress tests proved useful for measuring relaxation.


Descriptors :   *STRESS RELAXATION , AGING(MATERIALS) , COMPOSITE MATERIALS , STRESS TESTING , THESES , VISCOELASTICITY


Subject Categories : Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE