Sample | Coloring time (min) | βa (V/dec) | βc (V/dec) | Ecorr. (V) | Jcorr. (μA/cm2) | Corrosion rate (mm/year) | Polarization resistance (KΩ) |
---|---|---|---|---|---|---|---|
Al substrate | – | 125.67 | 106.99 | − 800.61 | 7.5914 | 0.08603 | 3.1803 |
Al colored by Ni | 30 | 220.1700 | 319.55 | − 723.28 | 3.7446 | 0.04082 | 3.2004 |
Al colored by Ni + Cu | 30 | 118.0990 | 190.24 | − 728.09 | 2.3794 | 0.06594 | 2.0165 |
Al colored by Cu | 30 | 23.6590 | 262.91 | − 718.54 | 7.8257 | 0.09114 | 1.4446 |