Reusable holders have been devised for evaluating high-temperature, plasma-resistant re-entry materials, especially fabrics. Typical material samples tested support thermal-protection-system damage repair requiring evaluation prior to re-entry into terrestrial atmosphere. These tests allow evaluation of each material to withstand the most severe predicted re-entry conditions.

In pursuit of this purpose, the holders are capable of supporting the material samples in a stagnation orientation (normal to the flow) with respect to the impinging plasma flow. The holder design allows rapid installation and change-out of 2.8 in. (≈ 71 mm) diameter samples and can accommodate sample thicknesses from fabrics to more than 0.5 in. (≈ 13 mm). Each holder consists of an interlocking set of rings, constructed of silicon carbide coated graphite, that clamp together concentrically in such a manner as to restrain the sample during a test. The sample is mounted in front of a washerlike backing plate to simulate the repair of a damaged section of reinforced carbon-carbon (RCC), such as that used on the Space Shuttle Orbiter.

This work was done by Joe Riccio of Johnson Space Center and Jim D. Milhoan of Lockheed Martin Corp. For more information, download the Technical Support Package (free white paper) at www.techbriefs.com/tsp under the Mechanics/Machinery category. MSC-24109-1