the range of potential applied to the test electrode in a potetiodynamic corrosion test, depends from different parameters even on the same type of material (due, for example, to the surface treatment, the corrosive solution, the scanning speed set for the measurement, etc. .).
I suggest you to have a look at the following paper/note:
-Potentiodynamic Corrosion Testing
Selin Munir, Matthew H Pelletier, William Robert Walsh
Journal of Visualized Experiments, 115 (2016)
Available on RG at: https://www.researchgate.net/publication/307625858_Potentiodynamic_Corrosion_Testing
-Corrosion and Coatings – Electrochemical testing by Gamry Instruments
Available at: https://www.gamry.com/application-notes/corrosion-coatings/
In particular the part: Potentiodynamic and Cyclic Polarization Scans
Available at: https://www.gamry.com/application-notes/corrosion-coatings/potentiodynamic-cyclic-polarization/