MLI endurance testing at high temperature (500 degrees C)

This paper describes the tests performed on MLI specimens to verify their integrity after 20 minutes exposure to 500 degrees C under vacuum conditions. In the test set-up, each MLI specimen wraps a metallic cage, defining a cylindrical enclosure. A high temperature IR source is located at the axis of the enclosure. In the test the IR source was powered until the applicable temperature level was reached. After assembly removal from the test chamber, each specimen was dismounted from the tooling and inspected. Mass and thermo-optical measurements were performed. Physical integrity was observed, without any tear on the blanket layers. The aluminium deposition on the Kapton layers showed no cracks. Sticky and carbonised deposits were found in the blanket coverlayers, coming from the specimens closing adhesive tapes and from velcros. The intermediate layers did not show degradation nor contamination.