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Solar Effects on Tensile and Optical Properties of Hubble Space Telescope Silver-Teflon Insulation

Published online by Cambridge University Press:  01 February 2011

Kim K. de Groh
Affiliation:
Kim.K.deGroh@nasa.gov, NASA Glenn Research Center, Electro-Physics Branch, 21000 Brookpark Rd., M.S. 309-2, Cleveland, OH, 44135, United States, 216-433-2297, 216-433-2221
Joyce A. Dever
Affiliation:
Joyce.A.Dever@nasa.gov, NASA Glenn Research Center, Electro-Physics Branch, 21000 Brookpark Rd., M.S. 309-2, Cleveland, OH, 44135, United States
Aaron Snyder
Affiliation:
Aaron.Snyder-1@nasa.gov, NASA Glenn Research Center, Electro-Physics Branch, 21000 Brookpark Rd., M.S. 309-2, Cleveland, OH, 44135, United States
Sharon Kaminski
Affiliation:
sharebear1022@hotmail.com, Hathaway Brown School, 19600 North Park Blvd., Shaker Heights, OH, 44122, United States
Catherine E. McCarthy
Affiliation:
Moonshadow320@aol.com, Hathaway Brown School, 19600 North Park Blvd., Shaker Heights, OH, 44122, United States
Allison L. Rapoport
Affiliation:
OhAngelene@aol.com, Hathaway Brown School, 19600 North Park Blvd., Shaker Heights, OH, 44122, United States
Rochelle N. Rucker
Affiliation:
seachell07@yahoo.com, Hathaway Brown School, 19600 North Park Blvd., Shaker Heights, OH, 44122, United States
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Abstract

During the fourth servicing mission of the Hubble Space Telescope (HST), the second set of solar arrays (SA-II) was replaced with a third set and the SA-II was brought back to Earth. A section of the retrieved SA-II solar array drive arm (SADA) multilayer insulation (MLI), which experienced 8.25 years of space exposure, was provided to NASA Glenn Research Center for environmental durability analyses of the top layer of silver-Teflon fluorinated ethylene propylene (Ag-FEP). Because the SADA MLI had solar and anti-solar facing surfaces and was exposed to the space environment for a long duration, it provided a unique opportunity to study solar effects on environmental degradation of Ag-FEP, a commonly used spacecraft thermal control material. Therefore, the objective of this research was to characterize the degradation of retrieved HST SADA Ag-FEP with particular emphasis on solar radiation effects. Data obtained included tensile properties, solar absorptance, surface morphology and chemistry. The solar facing surface of the SADA was found to be extremely embrittled and contained numerous through-thickness cracks. Tensile testing indicated that the solar facing surface lost 60% of its mechanical strength and 90% of its elasticity while the anti-solar facing surface had ductility similar to pristine FEP. The solar absorptance of both the solar facing surface (0.155 ± 0.032) and the anti-solar facing surface (0.208 ± 0.012) were found to be greater than pristine Ag-FEP (0.074). Solar facing and anti-solar facing surfaces were microscopically textured, and locations of isolated contamination were present on the anti-solar surface resulting in increased localized texturing. Yet, the overall texture was significantly more pronounced on the solar facing surface indicating a synergistic effect of combined solar exposure and increased heating with atomic oxygen erosion. The results indicate a very strong dependence of degradation, particularly embrittlement, upon solar exposure with orbital thermal cycling having a significant effect.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

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References

1. Eesbeek, M. Van, Levadou, F. and Milintchouk, A., “Investigation on FEP from PDM and Harness from HST-SA1”, Proceedings of the Hubble Space Telescope Solar-Array Workshop, Noordwijk, the Netherlands, May 30-31, 1995, ESA WPP-77, 403–416 (1995).Google Scholar
2. Drolshagen, G., “Definition of the Space Environment for the HST Solar-Array 1”, Proceedings of the Hubble Space Telescope Solar-Array Workshop, Noordwijk, the Netherlands, May 30-31, 1995, ESA WPP-77, 53–65 (1995).Google Scholar
3. Dever, J. A., Groh, K. K. de, Banks, B. A., Townsend, J. A., Barth, J. L., Thomson, S., Gregory, T., Savage, W., High Performance Polymers, 12, 125139 (2000).Google Scholar
4. Rockwell International Corporation 1990, Rocketdyne Division, Specification RC 1800 Review C, p. 18.Google Scholar
5.Personal communication with Joshua Abel, Hubble Space Telescope CHAMP Program Lead Thermal Engineer, Lockheed Martin and Elisabeth Abel, Thermal Engineer, Lockheed Martin.Google Scholar
6. American Society for Testing and Materials ASTM D 638-95, “Standard Test Method for Tensile Properties of Plastics,” 1995.Google Scholar
7. ASTME 903-82, “Standard Test Method for Solar Absorptance, Reflectance, and Transmittance of Materials Using Integrating Spheres,” American Society for Testing and Materials, 1982, Re-approved 1992.Google Scholar
8. Henninger, John H., “Solar Absorptance and Thermal Emittance of Some Common Spacecraft Thermal Control Coatings,” NASA RP 1121, 1984.Google Scholar
9. Townsend, J. A., Hansen, P. A., Dever, J. A., Groh, K. K. de, Banks, B. A., Wang, L. and He, C., High Performance Polymers, 11, 8199 (1999).Google Scholar
10. Groh, K. K. de, Gaier, J. R., Hall, R. L., Espe, M. P., Cato, D. R., Sutter, J. K. and Scheiman, D. A., D A 2000 High Performance Polymers, 12, 83104 (2000).Google Scholar
11. Groh, K. K. de and Martin, M., Journal of Spacecraft & Rockets, Vol. 41, No. 3, 366372 (2004).Google Scholar
12. Reed, R. P., Schramm, R. E. and Clark, A. F., Cryogenics 13, 6782 (1973).Google Scholar