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Find Twin Boundaries

Group (Subgroup)

Statistics (Crystallographic)


This Filter identifies all Triangles between neighboring Features that have a σ = 3 twin relationship. The Filter uses the average orientation of the Features on either side of the Triangle to determine the misorientation between the Features. If the axis-angle that describes the misorientation is within both the axis and angle user-defined tolerance, then the Triangle is flagged as being a twin. After the Triangle is flagged as a twin, the crystal direction parallel to the Face normal is determined and compared with the misorientation axis if Compute Coherence is selected. The misalignment of these two crystal directions is stored as the incoherence value for the Triangle (in degrees). Note that this Filter will only extract twin boundaries if the twin Feature is the same phase as the parent Feature.


Name Type Description
Axis Tolerance (Degrees) float Degree of tolerance for angular distance from the [111] axis
Angle Tolerance (Degrees) float Degree of tolerance for angular deviation from 60o
Compute Coherence bool Whether to compute the coherence between the Face normal and the misorientation axis

Required Geometry

Image + Triangle

Required Objects

Kind Default Name Type Component Dimensions Description
Feature Attribute Array AvgQuats float (4) Specifies the average orienation of each Feature in quaternion representation
Feature Attribute Array Phases int32_t (1) Specifies to which Ensemble each Feature belongs
Ensemble Attribute Array CrystalStructures uint32_t (1) Enumeration representing the crystal structure for each Ensemble
Face Attribute Array FaceLabels int32_t (2) Specifies which Features are on either side of each triangle
Face Attribute Array FaceNormals double (3) Specifies the normal of each triangle. Only required if Compute Coherence is checked

Created Objects

Kind Default Name Type Component Dimensions Description
Face Attribute Array TwinBoundary bool (1) Specifies whether a given Face belongs to a twin boundary
Face Attribute Array TwinBoundaryIncoherence float (1) Angle in degrees between crystal direction parallel to Face normal and misorientation axis

Example Pipelines

Please see the description file distributed with this Plugin

DREAM.3D Mailing Lists

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