Open Matlab File in the Editor MTEX

MTEX - Grain Analysis of EBSD Data

Analysis of single orientation measurement.

Specify Crystal and Specimen Symmetry

% specify crystal and specimen symmetry
CS = {...
  'not Indexed',...
  crystalSymmetry('m-3m','mineral','Fe'),... % crystal symmetry phase 1
  crystalSymmetry('m-3m','mineral','Mg')};   % crystal symmetry phase 2

Import ebsd data

fname = fullfile(mtexDataPath,'EBSD','85_829grad_07_09_06.txt');

ebsd = loadEBSD(fname,'CS',CS,'interface','generic',...
  'ColumnNames', { 'Phase' 'x' 'y' 'Euler 1' 'Euler 2' 'Euler 3' 'MAD' 'BC'},...
  'Columns', [2 3 4 5 6 7 8 9],'Bunge','IgnorePhase',0);

plotx2east

Plot Spatial Data

plot(ebsd('Fe'))

Segmentation

grains = calcGrains(ebsd,'angle',10*degree)
 
grains = grain2d  
 
 Phase  Grains  Mineral  Symmetry  Crystal reference frame  Phase
     1     946       Fe      m-3m                                
     2     466       Mg      m-3m                                
 
 Properties: GOS, meanRotation
 

The reconstructed grains strongly depend on the specified threshold angle. These angles can be specified seperatly for different phases.

grains = calcGrains(ebsd,'angle',[0 10 5]*degree)
 
grains = grain2d  
 
 Phase  Grains  Mineral  Symmetry  Crystal reference frame  Phase
     1     946       Fe      m-3m                                
     2     470       Mg      m-3m                                
 
 Properties: GOS, meanRotation
 

Plot grain-boundaries

plot(grains.boundary,'color',[0.25 0.1 0.5])
%TODO: internal grain boundaries
hold on, plot(grains.boundary,'linecolor','red','linewidth',2)

on application of this would be to take a look on the grainsize distribution

hist(grains)

Accessing geometric properties

area(grains); perimeter(grains);
shapeFactor(grains);