The morphology, chemical, mechanical and corrosion characterization of starting materials, and Al and Al-Al 2 O 3 /Al coatings obtained by Cold Gas Spray and applied on common steel substrate were performed. An Al coating on a ground or grit blasted substrate, and Al-Al 2 O 3 /Al coating on ground mild carbon steel have been compared. The electrochemical results showed that the coatings protect the substrate for immersion times >2000 h due to the dense structure obtained by Al and Al-Al 2 O 3 . The electrolyte reaches the substrate only after 2000 h of immersion without wetting completely the coating/substrate interface. Coatings have resisted 3000 h of salt fog test.

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a b s t r a c tFe-based amorphous metallic coatings were prepared by Cold Gas Spray process. Through this study, the effects of the process conditions such as spraying distance, gas pressure and temperature on the microstructure of as-sprayed coatings are evaluated. Microstructural studies show that the coatings can present a densely layered structure with porosity below 0.5% and thickness around 800 lm depending on the process conditions. Precipitation of nanocrystals in as-sprayed coatings is observed and present results show its dependence on the thermal and kinetic energy implicated in the process. In general, when gas temperature and pressure decreased, in the studied range, coatings displayed a dense and amorphous structure.