Corrosion Rate · Tafel Analysis Back EN · ZH
Corrosion Engineering

Corrosion Rate · Tafel Analysis · Polarization Curve Calculator

Evans diagram plotting via Butler-Volmer equation, corrosion rate (mm/year · mpy) from corrosion current density. Material presets for steel, aluminum, and copper.

Parameters
Material / Environment Presets
Corrosion current density icorr 10.0 μA/cm²
Corrosion potential Ecorr -500 mV
Anodic Tafel slope βa 80 mV/dec
Cathodic Tafel slope βc 120 mV/dec
Temperature T 25 °C
pH 7.0
Material Properties
Atomic weight M (g/mol) 55.85
Valence n 2
Density ρ (g/cm³) 7.87
Wall thickness (mm) 10.0 mm
icorr (μA/cm²)
Corrosion rate (mm/year)
Corrosion rate (mpy)
Penetration life (years)
Evans Diagram (E vs log|i|)
Corrosion Rate vs Temperature (Arrhenius)

Theory

Butler-Volmer equation:

$$i = i_{corr}\left[\exp\!\left(\frac{\eta}{\beta_a/\ln10}\right) - \exp\!\left(-\frac{\eta}{\beta_c/\ln10}\right)\right]$$

Corrosion rate (Faraday's law):

$$CR\,[\text{mm/y}] = \frac{3.27 \times M \times i_{corr}}{n \times \rho}$$

$i_{corr}$ [μA/cm²], $M$ [g/mol], $n$ [valence], $\rho$ [g/cm³]

CAE Integration: Corrosion rate is used as input for FEM wall-thinning models and residual strength analysis. Evans diagrams are combined with EIS analysis for corrosion fatigue life calculations in LS-DYNA and Abaqus.