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The CrFeCoNi coating was fabricated by the laser remelting method. The microstructure of the coating was detected. The corrosion behavior of coating at different temperatures was investigated by electrochemical measurements. Potentiodynamic polarization test results indicated that the corrosion current density increased with the increase in corrosion solution temperature in 3.5 wt% NaCl and 0.5 mol/L H2SO4 solutions, suggesting that the CrFeCoNi coating exhibited higher resistance to corrosion attack at lower solution temperature. The breakdown potential of the CrFeCoNi coating exhibited a decreasing trend with increasing solution temperature in 3.5 wt% NaCl solution. This indicated that the passive film formed at low temperatures had higher stability. The electrochemical impedance spectroscopy test indicated that the CrFeCoNi coating possessed higher charge transfer resistance at lower solution temperatures. The corrosion mechanisms of the coating at different temperatures were also revealed.

CrFeCoNi and CrMnFeCoNi coatings were prepared by laser remelting method. The grain boundary characteristics distribution of both coatings was investigated by electron backscattered diffraction technique. The results showed that the CrFeCoNi coating exhibited higher fraction of low angle grain boundaries and S3 boundaries compared to the CrMnFeCoNi coating. The corrosion properties of the CrFeCoNi and CrMnFeCoNi coatings in 3.5 wt% NaCl solution were identified by electrochemical method and localized electrochemical impedance spectroscopy technique. The results indicated that the CrFeCoNi coating had a higher corrosion resistance than the CrMnFeCoNi coating. The better corrosion resistance of the CrFeCoNi coating could be attributed to the high fraction of S3 boundaries and low fraction of the high angle boundaries.