Corrosion resistance of cold-sprayed Ta coatings in very aggressive conditions

This study deals with the corrosion behaviour of high-pressure cold-sprayed Ta coatings, compared with Ta bulk material and inert-atmosphere plasma-sprayed Ta coatings. Electrochemical polarization and electrochemical impedance spectroscopy measurements are carried out in 1 M KOH solution; immersion tests are performed in 1 wt.% HF solution, and the resistance to high-temperature oxidation and molten salt attack is evaluated by hot corrosion tests. Moreover, the effect of substrate material (steel, Al and Cu) on the coating formation is investigated using FESEM.