The below is a polarization scan of a copper sample. After performing a corrosion rate analysis, this has been calculated to be reasonably low: 0.004 mm/yr, suggesting the copper could be suitable for use in this test solution. However, upon sweeping the potential anodically, from Ecorr, the current soon breaches the critical pitting current (as outlined in ASTM G61) and is this a red flag? Interestingly, there’s no hysteresis present.

What are the implications of this “type” of polarization curve and what might one expect in real life use?

Thanks!