The polarization curves of carbon steel in boiling 55%
LiBrt0.07 mol/L LiOH solution containing various concentrations
of PWVA are shown in Fig. 1. The anodic polarization
curves showed a passive potential region about 100mV wide at a
potential around 650mV and the passive current was about
15mA/cm2 when the solution did not contain PWVA inhibitor.
Adding PWVA inhibitor into the solution, both the anodic and
cathodic polarization current density decreased and the passive
potential region widened. When the concentration of PWVA was
300 mg/L, the passive current density decreased to about
6mA/cm2 and the passive potential region was about 300mV
wide. As the concentration of PWVA increased to 400 mg/L, the
anodic and cathodic polarization curves coincide with the former.
As you said, it is from a published paper. So the authors knew the results more than others. Why not copy and paste the discussion from the paper? So someone herein could discuss and help you understand the figure better.