2D digital image correlation visualizes deformations and strain over the entire visible specimen surface. The non-contact videoXtens extensometer records image series during the test, compares image by image, and calculates the displacement in a pre-defined facet field, where each facet includes a specified number of camera pixels. This data is used to create two-dimensional color strain maps, which allow you to analyze the specimen behavior at a glance.
ZwickRoell DIC makes local strains visible in 2D over the entire specimen surface:
- Color displays of specimen behavior provide indications of inhomogeneous local strain and other special features.
- You can also analyze complex specimens with notches, or components and non-homogeneous materials.
- Verify your live strain measurement results.
- Errors in the test arrangement, such as inaccurate specimen alignment quickly become visible.
The 2D DIC option does not require additional hardware. The software option is simply combined with the videoXtens and expands the already installed strain measurement system with an additional functionality.
This allows for live strain measurement with a single extensometer, after which the 2D DIC analysis can be carried out.
ZwickRoell array systems offer you high resolution combined with a large field of view. They include several cameras, such as the videoXtens 2-120 HP. This simply allows you to see more in 2D DIC mode.
1.Defining masks and grids
Easily define the image region to be analyzed by means of a mask.Using a toolbox of mask geometries such as circles or polygons, you can also create irregular masks or define recesses.You also have the option of using multiple masks for which different resolutions can be specified.
Three very helpful default settings are available to define the facets and resolution.Settings can also be individually selected or adjusted.Here, the distance from the specimen plane to the test axis can be individually adjusted.
2.Starting the correlation
The correlation is used to calculate the displacements and strains between facets using the parameters defined in the mask.Images such as those recorded after specimen fracture can be selectively deselected for the correlation.
You have a wide selection of analytical tools and displays at your disposal for the analysis process.
The color map and diagram are clearly displayed in a common analysis layout.Analytical tools, such as gauge lengths, can be dragged on the color map to move them, simultaneously displaying current values in the diagram – without time delay!
Results of the individual 2D DIC analysis tools are combined with the measured values of the live test via the test re-run option in testXpert.From these combinations, material characteristic values can be recalculated retrospectively.