Space Station Resistojets

Resistojets for space station auxiliary propulsion require both long life and multipropellant capability, and platinum dispersion strengthened with yttria and zirconia has been studied for possible use as a resistojet material. A series of propellant compatibility tests has been conducted, and the results are presented. Generally, on the basis of mass loss, there were no compatibility problems in any of the environments considered. Microscopy showed that the effect of the propellants on the surface of the platinum varied significantly; however material stability, as measured by grain growth, did not appear to be a major problem.