Results of a round robin test on grain boundary determination by image analysis in the DGM working group ‘Quantitative Structural Analysis’

The DGM working group “Quantitative Structural Analysis” (QGA, Quantitative Gefügeanalyse) within the Expert Committee “Materialography” is concerned with current issues and methods for analyzing micrographs. The following gives an overview of the focal areas and activities of this working group. Furthermore, the results of a round robin test on the determination of grain boundaries involving 28 participants from 12 different laboratories are presented. As part of the round robin test, grain sizes were determined in micrographs of various materials using both the line intercept method and grain boundary segmentation. In addition to reviewing the round robin test against the background of a comparison of the results of different laboratories and participants, special attention is paid to evaluating the various measurement parameters and image processing steps with regard to their precision. Best practice recommendations are drawn from this review.