Influence of Nano-Al₂O₃ Sealing on Corrosion Resistance of3Cr13Coatings Prepared by Arc Spraying

3Cr13coatings were fabricated on Q235steel substrate with thickness of about 150μm by arcspraying,and then the coatings were sealed by three different sealing reagents which were silicone resins withdifferent contents of nano-Al2O3isopropanol.The morphologies and phases of the coatings were analyzed by opticalmicroscopy(OM),scanning electron microscopy(SEM)and X-ray diffractionmeter(XRD).The corrosion resistanceof the coatings was evaluated by full immersion corrosion test,acetic acid salt spray corrosion test andelectrochemical corrosion test.The results show that the main phases of the 3Cr13coating wereα-Fe(Cr)andCr2O3,and the coating was typical layered accumulation structure with porosity of 11%.The corrosion resistance ofthe sealed-coatings was obviously better than that of the unsealed-coating.Moreover,sealing reagent of siliconeresin added 6% nano-Al2O3isopropanol improved the corrosion resistance of the coatings most significantly.