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<< Click to Display Table of Contents >> Navigation: Experiments > I - Electrochemical Frequency Modulation > Techniques > Electrochemical Frequency Modulation Trend > Electrochemical Frequency Modulation Trend - Experimental Sequence |
Run the Electrochemical Frequency Modulation Trend standard technique by selecting Experiment > Electrochemical Frequency Modulation > Electrochemical Frequency Modulation Trend from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the Electrochemical Frequency Modulation Trend.exp script is run in this window.
2.The script creates the Setup dialog box which becomes the active window and accepts changes in the experimental parameters. This Setup window remembers the experimental settings from the last time this script was run. To restore the parameters to the values defined in the script, click the Default button.
3.The script now obtains the use of the potentiostat specified during Setup and opens the data file using the Output name. If the potentiostat is in use or the file cannot be opened, the script returns you to the Setup dialog box. The file header information is written to the data file. This information is written to the file prior to data acquisition. If the experiment is aborted, the file contains only this information. This header information includes:
•Tags identifying possible analyses.
•The current time and date.
•A list of the Setup parameters.
4.The script conditions the electrode if you specified Conditioning in the Setup. Conditioning is done by applying a fixed potential for a defined time. It establishes a known surface state on the corrosion specimen. A plot of current versus time is displayed during the Conditioning.
5.The cell is turned off and the specimen's Eoc is measured. If an Initial Delay is turned on in the Setup, this step lasts for the time specified as the Delay Time, or until the potential stabilizes. If no Initial Delay is specified, this step only lasts long enough for Eoc to be measured. A plot of potential versus time is always displayed. The last measured potential is recorded as Eoc.
6.The cell is turned on and the composite, dual sine wave, waveform is applied to the cell. Current readings at fixed time intervals are taken during the experiment. If you selected Autorange, the current scale is automatically optimized at each point in the waveform. The measured potential and current are displayed during the measurement.
7.At the conclusion of the EFM measurement, the data is processed based on the Corrosion Type selected in the Setup Menu. The EFM Trend data point is written to the output file and the file is closed. The data point consists of Point number, Time, Rp, Corrosion Rate, Causality Factor 2, Causality Factor 3, Icorr, BetaA, and BetaC. If Diffusion control or Passive film has been specified, the unneeded Beta is recorded as NIL.
8.If the Total Time of the Trend experiment is not exceeded, the script checks the Repeat Time and delays if necessary. The sequence then repeats, beginning with step 5.
9.If the Total Time of the Trend experiment has been exceeded, the cell is turned off and the script pauses to allow you to view your Trend data. Clicking F2-Skip closes the experiment. View your recently collected EFM Trend data by opening the data file with the Echem Analyst 2™.