EFM Trend Analysis

The data file from an Electrochemical Frequency Modulation Trend experiment is normally analyzed by the Electrochemical Frequency Modulation Trend.Gscript data analysis package provided with the EFM software. This script produces the following pages:

Corrosion Rate/Icorr Chart

This page contains a graph of Corrosion Rate (y-axis) and Icorr (y2-axis) as a function of time. The Corrosion Rate is calculated assuming the Corrosion Type entered in the original setup. It cannot be changed.

Causality Factors Chart

This page contains a graph of Causality Factor 2 (y-axis) and Causality Factor 3 (y2-axis) as a function of time. These factors do not depend upon the Corrosion Type selected in the original setup.

Rp Chart

This page shows a plot of Polarization Resistance calculated from the EFM Intermodulation Spectrum. This plot does not depend upon the Corrosion Type selected.

Betas Chart

This page contains a graph of the Tafel constants calculated assuming the Corrosion Type entered in the original setup. It can not be changed. Both anodic and cathodic Tafel constants are calculated only for activation-controlled corrosion. Only the anodic Tafel constant is calculated for diffusion-controlled corrosion. Only the cathodic Tafel constant is calculated for corrosion limited by passivation.

Experimental Setup

The parameters and settings used to run the experiment are shown on this tab. Except for the sample’s Equivalent Weight and Density, the parameters shown on this tab cannot be changed or edited.

If you entered the Sample Area incorrectly when the experiment was run, you must edit the original data file (using Windows®NotePad ) to change the area.

Experimental Notes

The Experimental Notes are the notes you entered prior to the data-acquisition. You can edit the Notes in the analysis, and save them with the changes to an analysis data file.

Open Circuit Voltage

The open-circuit voltage that was recorded during the Init. Delay is shown on this tab.

Hardware Settings

The Hardware Settings page contains all of the potentiostat settings used during the run of the experiment.

Other pages that may appear

Curve

If you selected “Display Grid for each data table” under EFM Trend > Options, this tab shows the point number, time, Rp, Corrosion Rate, Causality Factor 2, Causality Factor 3, Corrosion Current, Anodic Beta, and Cathodic Beta for each point in the EFM Trend Chart.

Min/Max

This tab displays the last result of the EFM Trend > Min/Max command. This command operates on the y-axis of the chart that was viewed when the command was executed.

Average

This tab displays the last result of the EFM Trend > Average command. This command operates on the y-axis of the chart that was viewed when the command was executed.