SPACE ENVIRONMENTAL EFFECTS ON COLORED MARKER COATINGS AND ANODIZES

摘要

Colored marker coatings and anodizes are used on spacecraft surfaces as aids for the astronauts during Extra-Vehicular Activities (EVAs) and also during rendezvous and capture maneuvers. These materials must be stable in the space environment and withstand atomic oxygen, ultraviolet radiation, particulate radiation, thermal cycling, and high vacuum without significant change in optical and mechanical properties. A variety of colored marker coatings and anodizes have been exposed to simulated space environments at Marshall Space Flight Center and also to the actual space environment as part of the Passive Optical Sample Assembly (POSA) -I flight experiment. Colored marker coatings were developed by AZ Technology, Huntsville, AL, under a NASA contract for International Space Station (ISS). These include yellow, red, blue, and black paints suitable for EVA visual aids and ISS emblems. AaCron, Inc., Minneapolis, MN, developed stable colored anodizes, also in yellow, red, blue, and black, for astronaut visual aid coatings. These coatings were exposed in the laboratory to approximately 550 equivalent sun-hours (ESH) of solar ultraviolet radiation and approximately 1X10~(21) atoms/cm~2 of atomic oxygen in vacuum. Optical property measurements from before and after exposure showed good environmental stability. The AZ Technology yellow colored marker coating, designated TMJ-800IY, and all four AaCron colored anodizes were flown on the POSA-I. These coatings and anodizes maintained their optical properties within 3 percent after an 18-month exposure on an orbiting, active space station.