Comparative KAM Maps
Figure 1 is a KAM map generated by CrossCourt with settings applied to match the resolution available to the user of traditional EBSD systems. These systems use the Hough Transform to measure the orientation of the crystal -to an accuracy of 0.5 degrees. Increasingly this level of detail is inadequate for particular types of materials research, especially when it comes to measuring elastic stress and strain. It turns out that the standard KAM is too noisy for these purposes and therefore a different approach is required. CrossCourt uses cross-correlation techniques comparing one EBSD pattern with another in order to generate its mapping data -including the KAM. Below is an example of the same dataset with new settings applied to reveal more information about the specimen.
Figure 1. Conventional KAM
Figure 2. High Resolution KAM
Figure 2 shows a High Resolution (HR) KAM map, enabling misorientation measurements to within 1/100 degree. As you can see from the image above, we are now able to reveal far more detail in the specimen in what appears to be three distinct regions of behavior within the field of view.
CrossCourt is able to utilize this level of information and apply it to materials stress and strain analysis. Please take a look at some of the other data on the website describing the features and application of stress and strain measurement using our software tool.
Data courtesy of Oxford University, UK.