electrochemical corrosion testing techniques

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Electrochemical Corrosion Tests:

Electrochemical corrosion tests with the application of external current include the following dc techniques:

Linear Polarization Resistance (LPR) measurements;
Potentiodynamic polarization curves;
Electrochemical Potentiokinetic Reactivation (EPR) measurements for intergranular corrosion;
Current vs time curves (at a given potential);

and the following dc techniques

Electrochemical Impedance Spectroscopy (EIS);
Harmonic analysis.

Electrochemical corrosion tests without the application of external current (at the free corrosion poetntial) include the following techniques:

Electrochemical noise (EN) measurements - with a further separation into electrochemical potential noise (EPN) and electrochemical current noise (ECN);
Free corrosion potential measurements as a function of time.

References/Literature:

ASTM G5: Standard Reference Test Method for Making Potentiostatic and Potentiodynamic Anodic Polarization Measurements.

ASTM G59: Standard Test Method for Conducting Potentiodynamic Polarization Resistance Measurements.

ASTM G61: Standard Test Method for Conducting Cyclic Potentiodynamic Polarization Measurements for Localized Corrosion Susceptibility of Iron-, Nickel-, or Cobalt-Based Alloys.

ASTM G102: Standard Practice for Calculation of Corrosion Rates and Related Information from Electrochemical Measurements.

ASTM G106: Standard Practice for Verification of Algorithm and Equipment for Electrochemical Impedance Measurements.

Links:

Electrochemical corrosion tests.

ASTM International
www.astm.org