Anti-corrosion properties of NiCr amorphous coatings sprayed by magnetron sputtering

ABSTRACT

NiCr amorphous alloy coatings were deposited by magnetron sputtering at different sputtering current for corrosion resistance. X-ray diffraction performed that the coating was constituted of nearly amorphous phase and nanocrystalline phase. The corrosion resistance of coatings were tested by the copper accelerated acetate spray (CASS) test and in the 3.5wt% NaCl solution, respectively. Corrosion behaviours of coatings were also examined in NaCl 3.5 wt% electrolyte by electrochemical workstation. The results indicate that the self-corrosion potential of the NiCr amorphous coatings shifted to more positive potential compared to crystalline NiCr coating, which indicates that the NiCr amorphous coating has more excellent corrosion resistance, especially the coating obtained under the sputtering current of 30 A. At this time, the corrosion potential was −31 mV, and the corrosion current density was 0.13 μA cm⁻², which could supply a reference for practical anti-corrosion application in pumps, ship impellers and automobile hubs.

KEYWORDS:

• NiCr coatings
• magnetron sputtering
• amorphous structures
• corrosion

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study is financially supported by Hebei key research and development plan project [grant number 18211009D].