Abstract: Low earth orbit (LEO) space missions have been shown that ambient atomic oxygen (AO) environment interacts with spacecraft materials, resulting in surface erosion and significantly affecting the performance of the materials. To ensure durability, the spacecraft operating in the LEO requires protective coatings. The erosion behaviors of copper and Al2O3 coatings were studied when exposed in AO environment of the ground based simulation facility. The chemical and physical changes of sample surfaces after exposed to AO fluxes were investigated with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The results indicate that copper undergoes slightly degradation, including mass gain and changes of surface morphology and electrical property; Al2O3 coatings have good AO erosion resistance, can provide protection for substrate materials. XPS analysis indicates that the surface of copper exposed to AO fluxes is composed mainly of CuO. Reactive sputtering prepared Al2O3 coatings are substoichiometric with an aluminum sufficiency, its mass increases at the initial stage of AO exposure, this is because of the transformation of substoichiometric to fully stoichiometric due to oxidation.
Protection of copper from atomic oxygen by copper- based Al2O3 coatings
Abstract：
Low earth orbit (LEO) space missions have been shown that ambient atomic oxygen (AO) environment interacts with spacecraft materials, resulting in surfa ce erosion and significantly affecting the performance of the materials. To ensu re durability, the spacecraft operating in the LEO requires protective coatings. The erosion behaviors of copper and Al 2O 3 coatings were studied when expose d in AO environment of the ground-based simulation facility. The chemical and p hysical changes of sample surfaces after exposed to AO fluxes were investigated with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (S EM). The results indicate that copper undergoes slightly degradation, including mass gain and changes of surface morphology and electrical property; Al 2O 3 c oatings have good AO erosion resistance, can provide protection for substrate ma terials. XPS analysis indicates that the surface of copper exposed to AO fluxes is composed mainly of CuO. Reactive sputtering prepared Al 2O 3 coatings are s ubstoichiometric with an aluminum sufficiency, its mass increases at the initial stage of AO exposure, this is because of the transformation of substoichiometri c to fully stoichiometric due to oxidation.
