Oxidation Tests on SEP-Samples in the Arc-heated Facility L2K - MSTP-ALSCAP-Program -.

Kurzfassung

Test samples developed by SEP in the frame of the alternative low cost short manufacturing cycle ceramic material programme (ALSCAP) of ESA were tested at three different test conditions in the arc-heated facility L2K. The surface pressure and temperature for each test sample were 10 hPa, 1350 centigrades; 100 hPa, 1350 centigrades; and 100 hPa, 1500 centigrades. While two test cycles were performed at 10 hPa, the samples, for the test point at 100 hPa, were exposed to four oxidation cycles. For comparison two samples were tested at each test point condition. The test duration at steady state surface conditions was 300 seconds. Higher mass losses were measured during the first test cycle for all three samples. A white protective layer developed during the initial phase of the first cycle was responsible for this phenomenon. Significant increase on the sample mass loss was noticed by increasing the surface pressure from 10 hPa to 100 hPa. The influence of the temperature change of about 150 centigrades on the results seems to be weak.