Description
Run the Cyclic Thermammetry standard technique by selecting Experiment > Critical Pitting Temperature > Cyclic Thermammetry from the Framework™ menu bar. This initiates the following sequence of events:
1.Framework™ creates a Runner window, and the Cyclic Thermammetry.exp script is run in this window.
2.The script creates the Setup dialog box and accepts changes in the experimental parameters.
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 Conditioning was specified 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.
6.If an Init. Delay is turned on in the Setup, this step lasts for the time specified as the Init. Delay time, or until the potential stabilizes . If no Init. 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.
7.The potential is set to the Applied E parameter value entered in Setup, and the cell is turned on. The temperature is set to Initial Temp, and the system delays until the measured cell temperature reaches the requested value. A current and measured temperature point is recorded. The temperature is stepped by the forward step size and the script pauses for one sample period. Another current and measured temperature point are recorded.
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The measured temperature and the requested temperature can be different if the speed of the temperature sweep is too high for the cell's thermal time constant. This process of stepping the temperature, delaying, and then recording a point continues until the requested temperature reaches the Apex Temp. At this point, the script switches to negative temperature steps. The reverse sweep continues until the requested temperature reaches the Final Temp. |
8.The scan ends and the data is written to the data file. The plot continues to be displayed until you click the F2-Skip button.