An aluminum impregnated nitrile rubber matrix referred to as AR-7 is a coating that has
been used to protect stainless steel flex hoses at NASA’s Kennedy Space Center launch
complex and hydraulic lines of the mobile launch platform (MLP). This coating has great
corrosion control performance and low temperature application. AR-7 was developed by
NASA and produced exclusively for NASA but its production has been discontinued due to its
high content of volatile organic compounds (VOC) and significant environmental impact. The
purpose of this project was to select and evaluate candidate coatings to find a replacement
coating that is more environmentally friendly, with similar properties to AR-7. No coatings were
identified that perform the same as AR-7 in all areas. Candidate coatings failed in comparison
to AR-7 in salt fog, beachside atmospheric exposure, pencil hardness, Mandrel bend, chemical
compatibility, adhesion, and ease of application tests. However, two coatings were selected
for further evaluation.
Keywords: flex hose coatings