The use of thermal atom test methods as a materials selection and screening technique for low-earth orbit (LEO) spacecraft is critically evaluated. The chemistry and physics of thermal atom environments are compared with the LEO environment. The relative reactivities of a number of materials determined in thermal atom environments are compared with those observed in LEO and in high-quality LEO simulations. Reaction efficiencies (cm3 atom-1) measured in a new type of thermal atom apparatus are one-thousandth to one ten-thousandth those observed in LEO, and many materials showing nearly identical reactivities in LEO show relative reactivities differing by as much as a factor of eight in thermal atom systems. A simple phenomenological kinetic model for the reaction of oxygen atoms with organic materials can be used to explain the differences in reactivity in different environments. Certain specific thermal atom test environments can be used as reliable materials screening tools.
Materials Selection for Long Life in Low Earth Orbit: A Critical Evaluation of Atomic Oxygen Testing with Thermal Atom Systems
- Views Icon Views
- Share Icon Share
- Search Site
S. Koontz, K. Albyn, L. Leger; Materials Selection for Long Life in Low Earth Orbit: A Critical Evaluation of Atomic Oxygen Testing with Thermal Atom Systems. Journal of the IEST 1 March 1990; 33 (2): 50–59. doi: https://doi.org/10.17764/jiet.2.33.2.c8846g147m0x7281
Download citation file: