Satellite Charging Control Materials.

Abstract : The secondary emission conductivity of silica fabrics and silica fabric/FEP/Aluminum composites under low energy electron irradiation has been studied. The dependence on electrical field of the conductivity across the samples has been shown. The surface potentials depend on the flux rate; the presence of low energy electron acting together with medium energy electrons decrease the potential values; the potential values increase with the time of exposure to vacuum and/or irradition, as well as with contamination build up. Teflon based conductive SSM with ITO coatings proved to be extremely vulnerable to thermal cycling and water absorption. A grounding technique based on a filled silicone adhesive proved to be applicable to this teflon based material and was stable during prequalification tests. The degradation of the samples was due to failure in the ITO coating rather than to a failure in the bonding/grounding technique. (Author)