The phaseSegmenter computer program enables the discrimination and segmentation of crystallographically identical/similar phases with grains of distinct orientation and slight compositional differences. The program uses reindexed EBSD datasets and EDS elemental data to compute grain-median compositional differences between grains of the phases in question and segments these by determination of an optimal threshold value.
The computer program was written and is executed within MATLAB. Further, the program makes use of the free crystallographic toolbox MTEX. Compatibility has been tested with MATLAB R2016b and MTEX 5.1.1. Since no advanced functions or functionalities of MATLAB or MTEX are applied, it is expected that the computer program is compatible for a wide range of the respective versions.
In the current version of phaseSegmenter, the EBSD input file format is cpr/crc and the output format is ctf. The MTEX import wizard can be used to interactively import other EBSD file formats and to generate a function for automation of this step.
EDS data can either be imported together with the cpr/crc EBSD data using MTEX or read in from comma-separated value (csv) files. When using OI Aztec as an EBSD/EDS software suite, the latter version allows to import the image data of processed EDS data (TruMaps) while the prior method seems to import unprocessed EDS data. Import through csv is therefore adviced to obtain a possibly strong compositional contrast as a foundation for phase discrination and segmentation.
Dr. Azdiar A. Gazder, Electron Microscopy Centre at University of Wollongong, is acknowledged for drafting the concept of this segmentation method and supporting the implementation in the phaseSegmenter computer program.