3.1 Tafel ExtrapolationTafel-Extrapolation
Summary
Tafel Extrapolation app is capable of calculating corrosion potential and corrosion current from a corrosion process curve which shows anodic and cathodic components of current.
Tutorial
- Activate an empty worksheet, then run the following script in the Script Window to import the data for this example.
fname$ = "%@ATafel Extrapolation\TafelData.dat";
impasc;
- Select Y column, and then select Plot: Basic 2D: Scatter menu to make a Scatter plot.
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- Make this newly created graph as the active window, then select the Tafel Extrapolation app icon
from the Apps panel to bring up the dialog.
- Keep the default settings for ROI Box tab, and check Append to Worksheet checkbox in Output tab.
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- Click OK button and go back to the graph.
- Drag the red and cyan cursor at the bottom/ top of X Axis to move the two vertical lines to the positions as the following image shows. And you can see the corresponding results are updated on the graph.
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- Click the
button, and then select New Output (O), then the result will be printed to Script Window.
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- Click the
button, and then select Go to Report Worksheet, then the report worksheet will be the active window to show the output results.
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Dialog Settings
ROI Box Tab
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Show Tool Name
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Specify whether to show the tool's name near the top left corner of the layer.
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Show on Graph
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Specify what to show on the graph.
- Tangent Point Coordinates
- Specify whether to show the XY coordinate of the tangent point on the graph.
- Anodic Tafel Slope
- Specify whether to show the anodic Tafel slope of anodic curve on the graph.
- Anodic Tafel Angle
- Specify whether to show the anodic Tafel angle of anodic curve on the graph.
- Anodic Curve Function
- Specify whether to show the expression of anodic curve function on the graph.
- Cathodic Tafel Slope
- Specify whether to show the cathodic Tafel slope of cathodic curve on the graph.
- Cathodic Tafel Angle
- Specify whether to show the cathodic Tafel angle of cathodic curve on the graph.
- Cathodic Curve Function
- Specify whether to show the expression of cathodic curve function on the graph.
- Ecorr and Icorr
- Specify whether to show the corrosion potential and corrosion current on the graph.
- E0, Icorr,a and Icorr,c
- Specify whether to show E0, Icorr,a and Icorr,c on the graph.
- Icorr in Nonlogarithmic Form
- Specify whether Icorr in Nonlogarithmic Form
- Logarithmic Base
- Specify Logarithmic Base. Available if above checkbox is checked.
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Color Setting
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Specify the corresponding object's displaying color, of which:
- Vertical Anodic Line Color
- Specify the color of the vertical line, which is used to select a point from the curve of graph, so to get the tangent line through this point as anodic curve.
- Vertical Cathodic Line Color
- Specify the color of the vertical line, which is used to select a point from the curve of graph, so to get the tangent line through this point as cathodic curve.
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Output Tab
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Output Quantities To
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Customize the output results
- Script Window
- Specify whether to output the results to Script Window.
- Results Log
- Specify whether to output the results to Results Log.
- Append to Worksheet
- Specify whether to append the results to a worksheet.
- Result Worksheet Name
- This is only available when Append to Worksheet is checked. It is used to specify the name of the worksheet.
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Quantities
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Specify the quantities to be outputted.
- Dataset Identifier
- Specify a dataset identifier.
- Tangent Point Coordinates
- Specify whether to output the XY coordinate of the tangent point.
- Anodic Tafel Slope
- Specify whether to output the anodic Tafel slope of anodic curve.
- Anodic Tafel Angle
- Specify whether to output the anodic Tafel angle of anodic curve.
- Anodic Curve Function
- Specify whether to output the expression of anodic curve function.
- Cathodic Tafel Slope
- Specify whether to output the cathodic Tafel slope of cathodic curve.
- Cathodic Tafel Angle
- Specify whether to output the cathodic Tafel angle of cathodic curve.
- Cathodic Curve Function
- Specify whether to output the expression of cathodic curve function.
- Ecorr and Icorr
- Specify whether to output the corrosion potential and corrosion current.
- E0, Icorr,a and Icorr,c
- Specify whether to output E0, Icorr,a and Icorr,c
- Keep Tangent Line
- Specify whether to keep Tangent Line after remove the Tafel Extrapolation gadget.
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Fly-out Menu
Click the button at the upper-right corner of the layer to expand the fly-out menu, which includes the following options.
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New Output (O)
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Output the results to the specified windows (Script Window or Results Log), and the specified worksheet (if not empty, append the results).
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Go to Report Worksheet
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Activate the report worksheet.
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Go to Source Worksheet
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Activate the source data worksheet.
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Output to Clipboard
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Output the results to clipboard.
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Fix ROI Position
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Specify whether to fix ROI position.
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Save Theme
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Save the settings as a theme.
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Save as <default>
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Save the settings as default theme.
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Load Theme
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Load theme settings.
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Preferences
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Open the TafelExtrapolation Preferences dialog.
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More Info
The following image shows the relationships about the calculating options.
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