Applied Science and Convergence Technology 2002; 11(2): 87-96
Published online June 1, 2002
Copyright © The Korean Vacuum Society.
Sang-hoon Lee,Hee-jun Seo,Guee-won Moon,Seok-weon Choi
"Outgassing from such sources as paints, coatings, adhesives and other non-metallic surfaces can contaminate satellites, especially second surface mirror and optical lens, it cause satellite to fail in own missions. The vacuum bake-out test using high temperature(more than 85 ℃)and high vacuum(less than 5.0×10^(-3) ㎩) certify that the components of satellite work properly and can survive and operate in space environment like high vacuum. In the bake-out chamber installed at SITC of KARI, Rotary vacuum pump and Booster pump produce low vacuum of 5.0 ㎩, and then two cryopumps produce high vacuum of below 5.0×10^(-3) ㎩. Also 48 ceramic heaters were provided to simulate high temperature.
During the vacuum bake-out test, we detected contaminants using RGA(Residual Gas Analyzer) and measure the outgassing rate of the contaminant using the TQCM(Thermoelectric Quartz Crystal Microbalance). Also, IR/UV Spectrometer and witness plate be used to certify that the components were suitable for the spacecraft.
This paper includes the preparation and procedures of the bake-out test for SAR(Solar Array Regulator) and MLI(Multi Layer Insulator), which were the components of the spacecraft. Especially, we discussed the methods and results of the contamination measurement. In the bake-out for SAR, the contamination was measured continuously although it was on the decrease from TQCM results. And RGA established that it is a highly polymerized compound. In the MLI bake-out using RGA and witness plate, we didn't detect any contamination materials."