Accelerated Creep Test Methodologies for Space Habitat Softgood Structural Materials

Space habitatnbsp;inflatable structures require complex material configurations and manufacturing processes. There is a need to develop a standardized accelerated creep test methodology with analysis capability to compute the master creep curves for high strength Vectran webbing to ensure long-term habitat structural stability.nbsp; Texas Research Institute Austin, Inc. (TRI Austin) proposes to develop a modified Step-Isothermal Method (SIM) and alternative Accelerated Life Testing methods that can be used for Vectran webbing and yarn based on our Phase I efforts.nbsp; In Phase II of the program TRI Austin is teaming with Dr. Brown of Clemsonrsquo;s Center for Advanced Engineering Fibers and Films to characterize the tensile properties of Vectran fibers, as well as using techniques to identify the effect of fiber microstructure, molecular architecture, and intermolecular interactions on Vectran long-term creep behavior.nbsp; Bally Ribbon Mills will provide expertise in webbing design and manufacturing processes used in its construction and currently manufactures the 24K 2-inch webbing for ILC Dover#39;s prototype space habitat. OTEX, who manufactured the 12.5K 1-inch Vectrannbsp;used in Phase I, will assist by supplying new webbing and yarn with QA/QC lot testing data. The Phase II program has 14 technical objectives based on our discoveries and theories from the Phase I evaluations that will be addressed in Phase II. In Phase IInbsp;we can test and address the impact of manufacturing defects, long-term storage, packaging (folding), transportation to space, and final deployment in space with accelerated aging protocols. These test articles will then be assessed with the developed testing protocols to determine mission profile-based reliability performance calculated based on probability and confidence level to estimate field use life.