Grain boundaries generation

To work with grain boundaries we need some ebsd data and have to detect grains within the data set.

% load some example data
plottingConvention.default('y↑→x');
mtexdata twins

% detect grains
[grains,ebsd] = calcGrains(ebsd)

% smooth them
grains = grains.smoothBoundary

% visualize the grains
plot(grains,grains.meanOrientation)

ebsd = EBSDsquare (y↑→x, row↑→col)
 
 Phase  Orientations     Mineral         Color  Symmetry  Crystal reference frame
     0     46 (0.2%)  notIndexed          none                                   
     1  22833 (100%)   Magnesium  LightSkyBlue     6/mmm        X||a*, Y||b, Z||c
 
 Properties: bands, bc, bs, error, mad, oldId
 Scan unit : um
 X x Y x Z : [0 → 50] x [0 → 41] x [0 → 0]
 Normal vector: (0,0,1)
 Square grid  :137 x 167
 
 
grains = grain2d (y↑→x)
 
 Phase  Grains  Pixels    Mineral  Symmetry         Color
     1     121   22833  Magnesium     6/mmm  LightSkyBlue
 
 boundary segments: 3825 (1149 µm)
 inner boundary segments: 4 (1.2 µm)
 triple points: 114
 
 Properties: meanRotation, GOS
 
 
ebsd = EBSDsquare (y↑→x, row↑→col)
 
 Phase  Orientations     Mineral         Color  Symmetry  Crystal reference frame
     0   14 (0.061%)  notIndexed          none                                   
     1  22865 (100%)   Magnesium  LightSkyBlue     6/mmm        X||a*, Y||b, Z||c
 
 Properties: bands, bc, bs, error, mad, oldId, grainId
 Scan unit : um
 X x Y x Z : [0 → 50] x [0 → 41] x [0 → 0]
 Normal vector: (0,0,1)
 Square grid  :137 x 167
 
 
grains = grain2d (y↑→x)
 
 Phase  Grains  Pixels    Mineral  Symmetry         Color
     1     121   22833  Magnesium     6/mmm  LightSkyBlue
 
 boundary segments: 3359 (954 µm)
 inner boundary segments: 3 (0.95 µm)
 triple points: 114
 
 Properties: meanRotation, GOS

Now we can extract from the grains its boundary and save it to a separate variable

gB = grains.boundary

gB = grainBoundary (y↑→x)
 
 Segments  length   mineral 1  mineral 2
      608  182 µm  notIndexed  Magnesium
     2751  772 µm   Magnesium  Magnesium

The output tells us that we have 3219 Magnesium to Magnesium boundary segments and 606 boundary segments where the grains are cut by the scanning boundary. To restrict the grain boundaries to a specific phase transition you shall do

gB_MgMg = gB('Magnesium','Magnesium')

gB_MgMg = grainBoundary (y↑→x)
 
 Segments  length  mineral 1  mineral 2
     2751  772 µm  Magnesium  Magnesium

Properties of grain boundaries

A variable of type grain boundary contains the following properties

misorientation
direction
segLength

These can be used to colorize the grain boundaries. By the following command we plot the grain boundaries colorized by the misorientation angle

plot(gB_MgMg,gB_MgMg.misorientation.angle./degree,'linewidth',2)
mtexColorbar

Citing this page. This page is part of the documentation of MTEX, a free and open source MATLAB toolbox for analyzing and modeling crystallographic textures. It was written by The MTEX Developers and is published at https://mtex-toolbox.github.io/BoundaryTutorial.html. If you use MTEX, or reuse text or figures from this page, in your research, please cite

F. Bachmann, R. Hielscher, H. Schaeben: Texture Analysis with MTEX - Free and Open Source Software Toolbox, Solid State Phenomena 160 (2010), 63-68. 10.4028/www.scientific.net/SSP.160.63

BibTeX

@article{bachmann2010mtex,
  author  = {F. Bachmann and R. Hielscher and H. Schaeben},
  title   = {Texture Analysis with MTEX - Free and Open Source Software Toolbox},
  journal = {Solid State Phenomena},
  volume  = {160},
  pages   = {63-68},
  year    = {2010},
  doi     = {10.4028/www.scientific.net/SSP.160.63},
  url     = {https://doi.org/10.4028/www.scientific.net/SSP.160.63}
}

Other papers describing specific MTEX methods are listed under Publications — please cite the one that best fits your application. The MTEX source code is licensed under the GNU General Public License v2.0; the text and figures of this documentation are licensed under CC BY 4.0, which permits reuse — including by automated systems — provided The MTEX Developers and this page are credited.