Mechanical integrity of ceramic coatings on Kapton made by a dry aerosol deposition of lunar mare simulant

The purpose of this paper is to demonstrate the use of lunar regolith and the dry aerosol deposition (DAD) method to produce ceramic coatings on polyimide polymer, and to test their mechanical integrity. Ceramic films were produced on Kapton substrates using a custom-built DAD system and lunar mare simulant (LMS) feedstock. Ultrafine grains and impact densification were confirmed using atomic force and electron microscopy. Mechanical properties of the DAD–LMS Kapton samples were evaluated with indentation, tensile, and mandrel bend tests. DAD–LMS coatings tripled the hardness and doubled the indentation modulus of the Kapton surface. Coatings 3–16 µm thick did not have a predictable effect on the ultimate tensile strength or elongation to failure; however, the apparent modulus of elasticity did increase. The coatings were able to withstand significant bending before damage, with critical bend radii of 5 and 1.5 mm for 7.5 µm and 120 nm thicknesses, respectively. Modest heat treatment was shown to reduce the bending strain of coated substrates. Advanced ceramic coatings are of interest for the protection of space and satellite polymers from micrometeoroid impacts, radiation, and atomic oxygen. Lunar posts and habitats will require the development of space manufacturing techniques and in situ resource utilization.