EFM Analysis

Loading an Electrochemical Frequency Modulation data file loads the script Electrochemical Frequency Modulation.GScript, which generates the following tabs:

EFM Chart

This tab shows the I vs. t chart for all of the data collected. The data from the first cycle are not used for the EFM analysis.

FFT Table

This tab shows the Fourier Transform of the time series data shown in the EFM Chart.

Intermodulation Spectrum

The modulus (absolute value) of the first few entries in the FFT Table is shown on this tab. All of the frequencies used to calculate the corrosion current and causality factors appear in this spectrum. See the Basics of Electrochemical Frequency Modulation for information about the value of these frequencies.

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 the Sample Area was entered 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 enter prior to the data-acquisition. The Notes can be edited in the analysis, and saved 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.

EFM Results

The corrosion rate, Tafel constants, and Causality factors calculated from the Intermodulation spectrum are shown on this tab. The calculation is based on the Corrosion Type entered in the Setup Menu. The EFM Menu can be used to recalculate the results assuming a different Corrosion Type.

You may change the units of Corrosion Rate under Tools>Options>Units.

Other pages that may appear:

Curve

If you selected “Display Grid for each data table” under EFM>Options, this tab shows the point number, time, voltage, current, and overload status for each point in the EFM Chart.