Computer-aided method for aligning texture-measuring-sample data relating to a texture measurement and device for data processing for this purpose

Abstract

The invention relates to a computer-aided method for aligning texture-measuring-sample data relating to a texture measurement of a measuring sample (2), in particular for at least partially compensating for a deviation of a practical measuring-sample orientation from a theoretical measuring-sample orientation, wherein texture-measuring-sample data relating to a texture measurement (1) of the measuring sample (2) are obtained. It is provided that the method includes an alignment procedure in which, in particular iteratively: - in a preparation step: at least a first distribution of a family of lattice planes represented by the texture-measuring-sample data is specified; - in a comparison step: the first distribution of a family of lattice planes is compared with a corresponding second distribution of a family of lattice planes represented by texture reference data and / or a symmetry, in particular a spatial symmetry, of the first distribution of a family of lattice planes is evaluated; - in an orientation-error step: on the basis of the comparison or the evaluation in the comparison step, an orientation error is determined; - in an adaptation step: the texture-measuring-sample data are adapted, in particular spatially turned, such that the orientation error is reduced, in particular minimized. The invention also relates to a device for data processing and to a computer product for carrying out the method.

Description

[0001] Computer-aided method for aligning texture measurement sample data of a texture measurement and device for data processing therefor

[0002] The invention relates to a computer-aided method for aligning texture measurement sample data of a texture measurement of a measurement sample, in particular for at least partially compensating for a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation, wherein texture measurement sample data of a texture measurement of the measurement sample are obtained.

[0003] The invention further relates to a device for data processing.

[0004] Furthermore, the invention relates to a computer program product.

[0005] The prior art involves determining the texture of a polycrystalline sample using diffractometric measurement methods. Texture typically refers to the distribution of crystallographic orientations of the crystallites in the sample. Typically, this involves analyzing diffraction patterns formed by the diffraction of radiation, such as X-rays, electron beams, or neutron radiation, at a Krista II structure or at crystallographic lattice planes of the sample or crystallites in the sample, to determine the orientation distribution of the crystallite structures.The intensity distribution of a diffraction pattern can usually be reconstructed based on Bragg's law. Typically, a reflection angle at which an intensity maximum occurs can be assigned to a specific set of lattice planes (hkl), where h, k, and I denote Miller indices, with a defined inter-lattice spacing. A distribution of orientations of equivalent sets of lattice planes {hkl}, where orientations of lattice planes are usually represented by lattice plane normals to the lattice planes, is often represented in the form of pole figures as stereographic projections, each for a specific equivalent set of lattice planes.

[0006] To obtain reproducible texture measurement sample data, a sample coordinate system used for texture measurement is typically defined based on axes characterizing sample processing or sample geometry. The crystallographic orientation of a crystallite is typically described by a rotation that converts a crystallite coordinate system into the sample coordinate system. Axes of the crystallite coordinate system are typically oriented to crystallographic axes of the crystallite, and axes of the sample coordinate system are typically oriented to axes describing sample geometry or sample processing, for example, a rolling direction, a transverse direction, and a normal direction of the sample.The rotation between the coordinate systems can be specified using three Euler angles, which describe a sequence of three rotations to convert the coordinate systems into each other.

[0007] During texture measurement of crystal structures, a deviation typically arises due to sampling, sample preparation, and / or measurement setup between a practical sample orientation used for texture measurement, particularly the evaluation of diffraction patterns, and a theoretical sample orientation of the sample, which corresponds to an actual sample orientation, for example, an actual rolling direction of the sample. Typically, attempts are made to minimize this deviation by working precisely during sample preparation and accurately aligning the sample in a measuring device. As a rule, this is done by eye as best as possible.The resulting deviation is often associated with a loss of information and / or generally makes it difficult to compare different texture measurements and / or may be associated with an impairment of machining processes based on a texture measurement.

[0008] This is where the invention comes in. The object of the invention is to provide a method of the type mentioned above with which the texture determination of a measurement sample can be improved. In particular, the aim is to enable at least partial compensation of a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation in the texture measurement sample data for texture determination of the measurement sample.

[0009] A further aim is to provide a device of the type mentioned above with which the texture determination of a measurement sample can be improved. Furthermore, a further aim is to provide a computer program product of the type mentioned above with which the texture determination of a measurement sample can be improved.

[0010] The object is achieved according to the invention by a method of the type mentioned at the outset, if the method comprises an alignment procedure in which, in particular iteratively:

[0011] - in a processing step: at least one first lattice plane family distribution of a lattice plane family represented by the texture measurement sample data is specified;

[0012] - in a comparison step: the first lattice plane distribution is compared with a corresponding second lattice plane distribution represented by texture reference data and / or a symmetry, in particular a spatial symmetry, of the first lattice plane distribution is evaluated;

[0013] - in an orientation error step: an orientation error is determined based on the comparison or evaluation in the comparison step;

[0014] - in an adaptation step: the texture measurement sample data are adapted, in particular spatially rotated, so that the orientation error is reduced, in particular minimized.

[0015] The invention is based on the idea of ​​adapting, in particular spatially rotating, determined or measured texture sample data, which correspond to a crystal structure or crystallite structure of the sample, in a computer-aided manner, in particular by computer implementation, in such a way that a deviation contained in the texture sample data between a practical sample orientation of the sample and a theoretical sample orientation of the sample is at least partially compensated. This makes it possible to improve the accuracy of texture determination. Typically, the practical sample orientation is a sample orientation assumed for texture measurement, in particular evaluation of diffraction patterns, for example aligned with an assumed rolling direction of the sample. The texture sample data typically refer to the practical sample orientation or a practical sample coordinate system corresponding to this.The theoretical sample orientation of the sample or a corresponding theoretical sample coordinate system usually corresponds to an actual, in particular ideal, sample orientation, for example, aligned with an actual rolling direction of the sample. Typically, the deviation of the practical sample orientation from the theoretical sample orientation is a deviation, in particular an orientation deviation, of a practical sample coordinate system to which the texture measurement or texture sample data refers, usually from an ideal orientation of the practical sample coordinate system, commonly referred to as the theoretical sample coordinate system.The ideal orientation of the practical measuring sample coordinate system is usually an orientation to characteristic directions, in particular process directions, of the measuring sample, for example a rolling direction, a transverse direction and a rolling plane normal direction of the measuring sample.

[0016] Texture typically refers to a distribution, in particular of a totality, of crystallographic orientations, in particular of crystallites or grains, in the test sample or a test area of ​​the test sample. Processing of the test sample, for example by rolling, extruding, or forging the test sample, generally leads to regular deformation of grains or crystallites of the test sample along slip planes of the test sample. Due to crystal symmetries of the test sample, the texture of the test sample typically also exhibits symmetrical properties or relationships. The texture test sample data is typically determined, in particular measured, by a texture measurement, in particular by means of a diffractometric measurement of the test sample, usually with a diffractometer or with a microscope, in particular an electron microscope.The texture measurement of the measurement sample can be part of the method according to the invention, in particular as part of a measurement procedure of the method, wherein the measurement procedure is usually carried out before the alignment procedure. A lattice plane distribution of a lattice plane family represented by the texture measurement sample data is usually referred to as the first lattice plane distribution. A lattice plane distribution of a lattice plane family represented by the texture reference data is usually referred to as the second lattice plane distribution. The respective lattice plane can be specified as (hkl), where h, k, l denote Miller indices. The respective lattice plane family is usually an equivalent lattice plane family, usually specified as {hkl}. The respective lattice plane distribution, in particular the first and / or second lattice plane distribution, usually refers to a distribution of orientations of the lattice plane family, in particular their lattice planes.The orientation of a lattice plane family or lattice plane is usually represented by a lattice plane normal family or lattice plane normal to the lattice plane family or lattice plane, usually specified as a crystallographic orientation or direction. The respective lattice plane family distribution, in particular a distribution of orientations of the respective lattice plane family, in the test sample or a test area of ​​the test sample is often represented in the form of a stereographic projection, in particular a pole figure for the lattice plane family. The lattice plane families can be technically equivalent lattice plane families or the associated lattice plane normals can be technically equivalent lattice plane normals. The texture test sample data or the first lattice plane family distribution usually refers to a test area of ​​the test sample. The test area usually comprises several, in particular a large number, of differently crystallographically oriented crystallites orGrains of the sample.

[0017] The texture measurement sample data typically comprise a plurality of measurement point data sets, each of which specifies a crystallographic orientation of a material, in particular a crystal structure, at a measurement point, in particular on the measurement sample or the measurement area. For this purpose, the respective measurement point data set can have, in particular specify, a plurality of, in particular three, measurement point angles, frequently referred to as solid angles or orientation angles. The measurement point angles typically represent a respective crystallographic orientation of the material or the crystal II structure, in particular a measured or determined one. The measurement point data sets typically refer to a plurality of differently crystallographically oriented crystallites or grains of the measurement sample or the measurement area. The respective measurement point data set can refer to a crystallite or a grain, in particular its crystal II structure.As a rule, the three measuring point angles indicate the crystallographic orientation with respect to the practical measurement sample orientation, in particular a practical measurement sample coordinate system that is usually fixed to the measurement sample. The measuring point angles usually represent Euler angles. The Euler angles usually describe a sequence of three rotations in order to convert two coordinate systems, in particular a crystal coordinate system that is fixed to the crystal structure and the measurement sample coordinate system, into one another. This can be implemented, for example, using Bunge notation. The crystal structure-fixed coordinate system is usually a crystallite-fixed coordinate system, also referred to as a crystallite coordinate system. The crystallographic orientation can correspond to a lattice plane of a crystal structure, in particular a crystallite structure, of the measurement sample, in particular represent a lattice plane normal of a lattice plane family.It is expedient if a respective measuring point is combined, in particular by summarizing, several measuring points that are spatially adjacent with respect to a measuring position on the measuring sample and that describe the same crystallographic orientation. This can be done by summing up spatial extension variables, in particular area values, of a respective measuring sample region that correspond to the measuring points. The extension variables can be parts of the respective measuring point data sets. A measuring point or measuring point data set formed by such a combination can represent a grain or crystallite of the measuring sample. The texture measuring sample data can be obtained, in particular by making the texture measurement data available to the computer-assisted method and / or by determining, in particular measuring, the texture measurement data as part of the computer-assisted method with a texture measurement of the measuring sample.

[0018] The adaptation of the texture measurement sample data, in particular the respective measurement point angles, is preferably performed iteratively. The alignment procedure can form an iteration loop that is run multiple times. Texture measurement sample data adapted in the adaptation step can be used as input data for the processing step. The processing step, the comparison step, the orientation error step, and the adaptation step are typically executed sequentially in enumerated order, in particular in a respective iteration of the iteration loop.

[0019] It is practical if, particularly in the processing step, the respective lattice plane distribution, in particular the first lattice plane distribution and / or the second lattice plane distribution, is implemented, in particular is implemented, in the form of a spatial arrangement of representation points in an arrangement space, in particular in the form of a pole figure, representing the orientations of the lattice plane distribution. Typically, a position of a respective representation point in the respective arrangement space corresponds to a crystallographic orientation of the associated lattice plane family. The arrangement space is preferably mapped via a stereographic projection (and a geometric figure, the pole figure, is provided). The representation points can be referred to as poles. The pole figure typically represents a stereographic projection of the lattice plane normal representing the respective lattice plane family.Typically, the orientation of the respective lattice plane family of each crystallite or grain, in particular of the measurement region, is represented in the arrangement space, preferably in the pole figure, in particular its pole figure surface. Typically, the respective lattice plane designates an equivalent lattice plane family or is to be understood as such. An arrangement space corresponding to the first lattice plane family distribution can be referred to as a first arrangement space, in particular of a first pole figure, or an arrangement space corresponding to the second lattice plane family distribution can be referred to as a second arrangement space, in particular of a second pole figure. The arrangement space is often three-dimensional or two-dimensional. Expediently, the arrangement space can be a layer sphere surface of a layer sphere or a stereographic projection of the layer sphere surface, wherein a measurement sample region or the crystallite structure is imaginarily arranged in a center of the layer sphere.The layer sphere surface can be a surface of a, in particular upper, hemisphere of the layer sphere. The pole figure can be a stereographic projection of the layer sphere surface, as is customary in the art. Accordingly, in the processing step, the at least one first lattice plane family distribution of a lattice plane family can be implemented by at least one first pole figure of the lattice plane family, or in the comparison step, the first pole figure can be compared with a second pole figure represented by the texture reference data, in particular corresponding to this second pole figure, and / or a symmetry, in particular spatial, of the first pole figure can be evaluated. The symmetry usually refers to a spatial arrangement of the representation points in the arrangement space, in particular in the pole figure.The respective first lattice plane distribution and, in particular, the second lattice plane distribution corresponding thereto typically correspond to one another with respect to an identical, in particular equivalent, lattice plane distribution. The symmetry of the first lattice plane distribution, in particular representation points in the arrangement space, can refer to one or more types of symmetry. The types of symmetry can expediently be rotational symmetry and / or axial symmetry and / or point symmetry. The axial symmetry can refer to a symmetry with respect to one or more axes of symmetry.

[0020] The symmetry preferably comprises or is an axial symmetry with respect to one or more axes of symmetry. The respective axis of symmetry typically runs through the arrangement space, in particular a zero point of a coordinate system of the arrangement space. The axis of symmetry can be an axis of the coordinate system, for example a horizontal or a vertical axis of the coordinate system. Evaluations of symmetries for different first lattice plane family distributions can be carried out with respect to different types of symmetry, in particular axes of symmetry. Depending on a particular lattice plane family to which the respective first lattice plane family distribution refers, an evaluation with respect to a different type of symmetry, in particular axes of symmetry, can be advantageous.

[0021] In the comparison step, the comparison between the first lattice plane family distribution and the second lattice plane family distribution can be carried out based on a respective spatial arrangement, in particular density distribution, of the representation points in the arrangement space, in particular in a respective pole figure, and / or the evaluation of the symmetry of the first lattice plane family distribution can be carried out based on a spatial arrangement, in particular density distribution, of the representation points in the arrangement space, in particular in the pole figure.

[0022] It is advantageous if the alignment procedure comprises a raster step, wherein in the raster step the respective arrangement space is divided into spatial elements, in particular area elements, using a raster, wherein an intensity value is assigned to the respective spatial element based on a number, in particular density, of display points located in the respective spatial element. The density can relate to a relative proportion of a number of the display points in the respective spatial element or can be formed with or by such a density. The respective spatial element can be referred to as a cluster, wherein the cluster has the intensity value of the respective spatial element. In this way, a density representation of the display points can be implemented in a practical manner. The intensity value orThe density of the respective spatial element can be represented by, in particular by, a relative proportion of a number of representation points in the spatial element in relation to a number of representation points in the other spatial elements or a total number of representation points in the arrangement space. For example, the intensity value or the density can be formed by, in particular by, a ratio of the number of representation points in the respective spatial element to the total number of representation points in the arrangement space, in particular averaged over all spatial elements of the arrangement space. If the arrangement space is a surface, in particular a pole figure or its pole figure surface, the spatial element is usually a surface element. The spatial elements formed with the grid, in particular surface elements, can be of the same size or different sizes. Preferably, the predominant, essentially entire arrangement space is divided into spatial elements using the grid.

[0023] If the arrangement space is represented with a spherical surface or a stereographic projection of the spherical surface, in particular with a pole figure, it is advantageous if the grid is formed with, in particular by, a spherical grid which divides the spherical surface into surface segments. If the arrangement space is the spherical surface, the surface segments can be the surface elements. If the arrangement space is represented with the stereographic projection, in particular a pole figure, it is advantageous if the grid which divides the stereographic projection, in particular a pole figure, into surface elements is implemented as a projection of the spherical grid, which preferably divides a spherical surface of an upper hemisphere of the spherical surface corresponding to the pole figure into surface segments.

[0024] It has proven useful if the sphere grid is formed with, in particular, grid lines, where the grid lines form meridians and parallels of latitude on the sphere surface. It is advantageous if the meridians are implemented with equidistantly spaced longitudes and / or the parallels of latitude are implemented with equidistantly spaced latitudes. The meridians usually run at a constant horizontal angle of the sphere and, in particular, are spaced from one another with equidistant horizontal angle steps of the horizontal angle. The parallels of latitude usually run at a constant vertical angle of the sphere and, in particular, are spaced from one another with equidistant vertical angle steps of the vertical angle. The horizontal angle is often referred to as the azimuth angle and the vertical angle as the altitude angle. The sphere surface of the upper hemisphere is usually divided into surface segments using the grid.The surface elements of the pole figure can represent a projection, in particular a stereographic one, of the surface segments of the layer sphere surface. The horizontal angle can have an angular range from 0° to 360°. The vertical angle can have an angular range from 0° to 90°. Preferably, the horizontal angle step is a divisor of 360° and / or the vertical angle step is a divisor of 90°. Alternatively, it is particularly preferred if the horizontal angle step and the vertical angle step are each a divisor of 360° and 90°. By selecting a surface element size, in particular the horizontal angle step and / or the vertical angle step, a resolution defined by the grid can be influenced. It is advantageous if the distance between adjacent longitudes or the horizontal angle steps is from 5° to 30°, in particular 5° to 15°, preferably from 5° to 10°.It is advantageous if the distance between adjacent latitudes or the vertical angle increments are between 5° and 30°, in particular between 5° and 15°, preferably between 5° and 10°. It is useful, particularly in the grid step, to represent the respective first lattice plane distribution with a contour representation. Typically, iso-contour lines based on the intensity values ​​of the spatial elements or clusters are displayed in the arrangement space.

[0025] It is advantageous if, in order to compare the first lattice plane distribution with the corresponding second lattice plane distribution, in particular in the comparison step, a spatial arrangement, in particular a density distribution, of the display points in the arrangement spaces of the lattice plane distributions is compared with one another. For this purpose, the first arrangement space can expediently be compared with the respective second arrangement space. In order to compare the first lattice plane distribution with the corresponding second lattice plane distribution, spatially corresponding spatial elements or clusters of the arrangement space of the first lattice plane distribution and the arrangement space of the second lattice plane distribution can efficiently be compared with one another with regard to their intensity values. It is practical if the spatial elements are compared with one another by forming a difference between the respective intensity values.Typically, spatially corresponding spatial elements or clusters of the arrangement spaces are compared with each other with respect to the grid in the respective arrangement space. The arrangement space of the first lattice plane distribution and the arrangement space of the corresponding second lattice plane distribution can be divided into respective spatial elements using different grids or, preferably, an identical grid. Typically, a coverage error is formed based on the comparison. The coverage error can represent a deviation between the first lattice plane distribution and the second lattice plane distribution. The comparison of corresponding spatial elements can each result in a coverage error contribution, wherein a summary of the coverage error contributions, in particular with a summation of the coverage error contributions, forms the coverage error.For example, the respective coverage error contribution can be implemented by forming a difference between the intensity values ​​of the respective corresponding spatial elements or clusters, in particular by forming an absolute value of the difference formation. The coverage error can then be formed by summing the coverage error contributions. The coverage error can be an orientation error contribution, with which the orientation error is formed. For the comparison of the first lattice plane distribution with the second lattice plane distribution, the second lattice plane distribution is usually represented analogously to the first lattice plane distribution, in particular analogously to an implementation of the first lattice plane distribution in the processing step and / or in the raster step. This can take place as part of the method, in particular in the alignment procedure, for example in the processing step, raster step or comparison step.

[0026] It is advantageous if, usually in the comparison step, a symmetry, in particular a spatial symmetry of the spatial arrangement, in particular a density distribution, of the representation points in the arrangement space is evaluated to evaluate the symmetry of the first lattice plane distribution. In order to evaluate the symmetry, in particular a spatial symmetry of the first lattice plane distribution with respect to one another with respect to a symmetry axis, in particular a predetermined one, in the arrangement space, spatially corresponding spatial elements or clusters of the arrangement space of the first lattice plane distribution can expediently be compared with one another with respect to their intensity values. This is usually done in the comparison step. It is practical if the spatial elements are compared with one another by forming a difference between the respective intensity values. The comparison can be based on one or more, in particular predetermined, axes of symmetry.The respective axis of symmetry can be selectable or fixed, in particular by a user or automatically. For example, the axis of symmetry can be an axis of the respective arrangement space, in particular of a respective pole figure. Typically, a symmetry error is formed based on the comparison. The symmetry error can then represent a deviation from the symmetry, in particular a deviation between spatial elements or clusters that correspond to one another with respect to the respective axis of symmetry. The comparison of spatial elements or clusters that correspond to one another can each result in a symmetry error contribution, wherein a summary of the symmetry error contributions, in particular with a summation of the symmetry error contributions, can form the symmetry error.For example, the respective symmetry error contribution can be implemented by, in particular, forming a difference in the intensity values ​​of spatial elements or clusters corresponding to each other with respect to the respective symmetry axis, in particular by forming an absolute value of the difference. The symmetry error can then be formed by summing the symmetry error contributions. The symmetry error can be an orientation error contribution, with which the orientation error is formed.

[0027] It is advantageous if, in the preparation step, several first lattice plane family distributions of, in particular, different, lattice plane families are specified, and in the comparison step, the respective first lattice plane family distribution is compared with a second lattice plane family distribution, in particular corresponding to it, and / or a symmetry, in particular spatial, of the respective first lattice plane family distribution is evaluated. The comparison of the first lattice plane family distribution with the second lattice plane family distribution is usually carried out between mutually corresponding, in particular identical, lattice plane families.The comparison between the respective first lattice plane distribution and, in particular, the second lattice plane distribution corresponding thereto and / or the evaluation of the respective first lattice plane distribution with regard to its symmetry is preferably carried out separately for the respective, in particular first, lattice plane distribution, in particular with a separate comparison or a separate evaluation.

[0028] Typically, an orientation error contribution, in particular in the form of a respective coverage error or respective symmetry error, is formed based on, in particular resulting from, the comparison between the first lattice plane family distribution and the corresponding second lattice plane family distribution performed in the comparison step, or from the evaluation of the symmetry of the respective first lattice plane family distribution performed in the comparison step, in order to form the orientation error with the orientation error contributions, usually in the orientation error step. The formation of the respective orientation error contribution can take place as part of the comparison step.In the orientation error step, the orientation error can be determined, in particular formed, with the respective orientation error contribution, in particular by summing, for example, the orientation error contributions, in particular the absolute values ​​of the orientation error contributions. The summing, in particular summing, can be carried out with different weightings of the orientation error contributions, in particular depending on a respective comparison or evaluation in the comparison step on which the respective orientation error contribution is based.

[0029] A particular crystallographic orientation, in particular of a crystal structure or of a crystallite, can be described by a rotation, which represents a transition between a crystal-fixed crystal coordinate system, in particular a crystallite coordinate system, and a sample-fixed sample coordinate system. Typically, one or more axes of the crystal coordinate system are each oriented parallel to a lattice plane normal of a set of lattice planes of the crystal. The rotation can be specified in the technical standard with three Euler angles. Euler angles generally describe a sequence of three partial rotations. The crystallographic orientation can refer to an orientation of a particular set of lattice planes or lattice plane or particular Krista II structure. This applies in particular to crystallographic orientations that are or will be described by the texture sample data, in particular measurement point data sets.Typically, the practical sample orientation corresponds to a practical sample coordinate system or is specifically implemented by such a system. Typically, the theoretical sample orientation corresponds to a theoretical sample coordinate system or is specifically implemented by such a system. The texture sample data typically refers to the practical sample coordinate system. The axes of the respective sample coordinate system are typically oriented orthogonally to each other.

[0030] As a rule, the practical measurement sample coordinate system is, in particular is, aligned, in particular with deviations or approximately, to one or more characteristic directions of the measurement sample assumed for texture measurement, in particular process directions, so that the texture measurement data usually refer to the practical measurement sample coordinate system. The theoretical measurement sample coordinate system usually represents an alignment, in particular an ideal alignment, of the practical measurement sample coordinate system to the characteristic directions, in particular process directions. A deviation of the practical measurement sample orientation from the theoretical measurement sample orientation can be represented by a rotation, with which the practical measurement sample coordinate system and the theoretical measurement sample coordinate system can be converted into one another. The rotation can be specified with three Euler angles.The adjustment of the texture measurement sample data can correspond to this rotation. The process direction can, for example, be a rolling direction and / or extrusion direction and / or growth direction of the measurement sample. The respective measurement sample coordinate system is often aligned such that the axes of the measurement sample coordinate system are aligned according to a rolling direction, a transverse direction, and a rolling plane normal direction of the measurement sample, which directions are usually oriented orthogonally to each other. The rolling direction and the transverse direction are usually parallel to a surface of the measurement sample or lie within it.

[0031] It is advantageous if the texture reference data are texture comparison sample data from a texture measurement of a comparison sample or, in particular, theoretical texture data. The texture reference data, in particular texture comparison sample data, can be implemented, in particular represented, according to the texture measurement sample data. The texture reference data typically describes a texture, in particular of the comparison sample. The comparison sample is typically another measurement sample, such as a reference measurement sample, in particular with properties corresponding to the measurement sample, in particular concerning a crystallographic texture.

[0032] In the adaptation step, the texture measurement sample data is typically spatially rotated, in particular such that the orientation error is reduced, in particular minimized. A rotation of the texture measurement data can be expediently determined which, when applied to the texture measurement sample data, reduces, in particular minimizes, the orientation error. The rotation can be described or performed using Euler angles, in particular by varying Euler angles. The Euler angles typically describe a sequence of several, usually three, partial rotations of the texture measurement sample data.

[0033] High efficiency can be achieved if the texture sample data is adapted with iterative adaptation of the texture sample data, usually with an optimization method, in particular with a derivative-free optimization method, preferably a downhill simplex method, with a reduction of the orientation error. The respective iterative adaptation can expediently be carried out by determining and / or performing a rotation, in particular as mentioned above, of the texture sample data. The iterative adaptation can be implemented by the alignment procedure forming an iteration loop, which is run through in multiple iterations. Typically, the alignment procedure is run through in the respective iteration, with texture sample data adapted in the adaptation step being used as input data for the processing step of the respective next iteration.A respective iteration of the iteration loop can comprise the processing step, preferably the raster step, the comparison step, the orientation error step, and the adaptation step, wherein texture measurement sample data adapted in the adaptation step are typically used as input data for the processing step of the next iteration. The processing step, preferably the raster step, the comparison step, the orientation error step, and the adaptation step can be performed one after the other in enumerated order, in particular, can be run through, in particular in the respective iteration of the iteration loop.It is advantageous if, based on the adaptations, in particular rotations, of the texture measurement sample data carried out in the adaptation step, an adaptation instruction, in particular a rotation instruction, for example in the form of one or more rotation angles, is defined, which represents an overall adaptation of the texture measurement sample data, usually the respective measurement point angle, in particular across iterations. This can be done as part of the method, in particular the alignment procedure, preferably the adaptation step. It is advantageous if further texture measurement sample data and / or a texture measurement of the measurement sample, in particular corresponding to the texture measurement sample data, are adapted based on the adaptations of the texture measurement sample data carried out in the adaptation step, in particular based on or according to the adaptation instruction.In this way, the deviation between the practical measurement sample orientation and the theoretical measurement sample orientation for the additional texture measurement sample data or the texture measurement can be at least partially compensated. The method can comprise an accommodation procedure, in particular following the alignment procedure, in which this is carried out. The adaptation can be a rotation, in particular a spatial rotation, of the additional texture measurement sample data and / or of the measurement sample relative to a measurement section with which the texture measurement is carried out. The additional texture measurement sample data can be obtained in the method, in particular made available to the method. The additional texture measurement sample data can be implemented analogously to the texture measurement sample data.

[0034] It can be advantageous if the texture measurement sample data is determined as part of the method, in particular with a texture measurement of the measurement sample. The texture measurement is usually a diffractometric and / or microscopic, in particular electron microscopic, measurement of the measurement sample. The texture measurement is usually carried out by diffracting radiation on the measurement sample, in particular its crystal structure, whereby a diffraction characteristic, in particular a diffraction pattern, is usually measured. The radiation can be electromagnetic radiation or photon radiation, for example light radiation, UV radiation, or X-rays, or electron radiation or neutron radiation. This can be implemented using a diffractometer and / or microscope, in particular a photon microscope or electron microscope.It is practical if the texture measurement is carried out using electron backscatter diffraction (EBSD), in particular with an electron microscope.

[0035] The adaptation, in particular rotation, of the texture measurement sample data in the adaptation step typically relates to an adaptation, in particular rotation, of the measurement point data sets of the texture measurement sample data. In this way, an alignment of the texture measurement sample data can be implemented. The adaptation of the texture measurement sample data, in particular of the measurement point data sets, can expediently be carried out by changing at least one, several, or all of the measurement point angles of the respective measurement point data set. The adaptation can relate to one, several, or all of the measurement point data sets. The adaptation is typically a spatial rotation of the measurement point data sets, in particular with a corresponding change of the respective measurement point angles, in particular of the respective measurement point data set. The compensation of the deviation of the practical measurement sample orientation from the theoretical measurement sample orientation can be carried out at least partially, in particular essentially entirely.Compensating for the deviation of the practical measurement sample orientation from the theoretical measurement sample orientation can be compensating for the deviation in the texture measurement sample data or in a corresponding texture measurement of the measurement sample. The respective first lattice plane family distribution represented by the texture measurement sample data can be part of the texture measurement sample data or can be formed correspondingly to, in particular based on, the latter. The respective second lattice plane family distribution represented by the texture reference data can be part of the texture reference data or can be formed correspondingly to, in particular based on, the latter. This can be part of the method, in particular of the processing step. The method can be used for determining the texture of the measurement sample or can be part of such a process.Typically, the procedure, in particular the alignment procedure and / or the accommodation procedure, is computer-implemented and / or automated.

[0036] The respective lattice plane distribution, in particular the first and / or second lattice plane distribution, and in particular its spatial arrangement of representation points in an arrangement space, for example in the form of a respective pole figure, can be implemented with or without a graphic representation. The respective lattice plane distribution, in particular the first and / or second lattice plane distribution, and in particular its spatial arrangement of representation points in an arrangement space, for example in the form of a respective pole figure, is usually implemented, in particular purely, computationally. This applies in particular to an implementation of the method, in particular the respective processing step, the comparison step, the orientation error step, and / or the adaptation step. Preferably, the respective step is carried out without a graphic representation of the respective lattice plane distribution and / or, in particular purely, computationally.This applies analogously to the alignment procedure and / or the accommodation procedure. Specifically, the comparison step, in particular the comparison of the first pole figure with the second pole figure or the evaluation of the symmetry of the first pole figure, can be performed with or without a visual representation of a respective pole figure and / or a respective grid. Preferably, this is performed without a visual representation, or the comparison step, in particular the comparison of the first pole figure with the second pole figure or the evaluation of the symmetry of the first pole figure, is performed purely computationally.

[0037] The computer-implemented method can be implemented with a computer and / or with one or more data processing means, for example a processor, in particular a microprocessor, a programmable circuit, in particular in the form of a field-programmable gate array, and / or an integrated circuit, in particular in the form of an application-specific integrated circuit, and / or a data processing structure based on optical components.

[0038] The aim is achieved according to the invention with a device for data processing of the type mentioned at the outset, if the device comprises means, in particular at least one processor, which are adapted to carry out the method described in this document, in particular above, for aligning texture measurement sample data of a texture measurement of a measurement sample, in particular to subject texture measurement sample data, in particular iteratively, to the alignment procedure in the manner described or to adapt it with this. The means can comprise, in particular be, a data processing means, such as a processor, in particular a microprocessor, and / or a programmable circuit, in particular in the form of a field-programmable gate array, and / or an integrated circuit, in particular in the form of an application-specific integrated circuit, and / or a data processing structure based on optical components.The means can expediently comprise a plurality of, in particular identical, data processing means. In particular, a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation contained in the texture measurement sample data or a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation present in a measurement setup for measuring the texture of the measurement sample can be at least partially, preferably essentially completely, compensated. The device can have a control means to compensate for a corresponding deviation. In particular, in this way a texture of the measurement sample can be determined with high accuracy, in particular as part of the method. It is understood that the device for data processing can be correspondingly oranalogous to the features, advantages, and effects described in the context of a method, in particular the above method, for aligning texture measurement sample data from a texture measurement of a measurement sample. This also applies analogously to the device with regard to the method.

[0039] It has proven useful if the device is designed as part of a diffractometer and / or a microscope, in particular a particle radiation microscope, for example a photon microscope, in particular a light microscope, or preferably an electron microscope, or is coupled to such a microscope for data transmission. The diffractometer or microscope, preferably an electron microscope, can be designed to perform a texture measurement of a sample, in particular the measurement sample. This enables particularly practical compensation of the deviation between the practical measurement sample orientation and the theoretical measurement sample orientation.The microscope, preferably an electron microscope, can have a diffraction pattern detector for detecting and / or displaying a diffraction pattern which is generated by irradiating a measurement sample examined with the microscope, preferably an electron microscope, with radiation, in particular a radiation as mentioned above, preferably electron radiation.

[0040] The further objective is achieved according to the invention with a computer program product of the type mentioned at the outset, if the computer program product contains instructions which, when executed by a computer or the aforementioned data processing device, cause the computer to execute the aforementioned method for aligning texture measurement sample data of a texture measurement of a measurement sample, in particular in the manner described in this document, to subject texture measurement sample data, in particular iteratively, to an alignment procedure or to adapt it with this. In particular, a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation contained in the texture measurement sample data or a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation present in a measurement setup for measuring the texture of the measurement sample can be compensated at least partially, preferably essentially entirely.The commands can provide for control of the aforementioned control means of the device to compensate for a corresponding deviation. In particular, a texture of the measurement sample can be determined with high accuracy in this way. It is expedient if the computer program product is designed as part of the data processing device or is installed on it as intended.

[0041] It is understood that the computer program product according to the invention can be designed correspondingly or analogously to the features, advantages, and effects described in the context of a method, in particular the above, for aligning texture measurement sample data of a texture measurement of a measurement sample or of a device, in particular the above, for data processing. This applies analogously in the reverse direction.

[0042] Advantageously, a computer-readable storage medium is provided on which the computer program product is stored. This enables a practical implementation of the computer program product or implementation of the method for aligning texture measurement sample data of a texture measurement of a measurement sample. The storage medium can be designed as a volatile or non-volatile storage medium. The storage medium can expediently be designed as part of the aforementioned data processing device. Further features, advantages, and effects will become apparent from the exemplary embodiments presented below. The drawings, to which reference is made, show:

[0043] Fig. 1 is a schematic representation of a texture measurement of a test sample;

[0044] Fig. 2 is a schematic representation of the test sample of Fig. 1 with the practical test sample coordinate system, theoretical test sample coordinate system and crystal coordinate system shown;

[0045] Fig. 3 to Fig. 5 schematic representations of three characteristic lattice planes of a cubic crystal;

[0046] Fig. 6 is a schematic representation of a layer sphere with a cubic crystal arranged in the center;

[0047] Fig. 7 shows a pole figure corresponding to the position sphere of Fig. 6 with poles of an upper hemisphere of the position sphere shown;

[0048] Fig. 8 to Fig. 10 Pole figures determined by electron backscatter diffraction measurement of an Al alloy;

[0049] Fig. 11a is a graphic representation of a pole figure with a grid drawn in the pole figure;

[0050] Fig. 11b a graphic representation of a layer sphere with layer sphere grid and corresponding surface segment and surface element;

[0051] Fig. 12 to Fig. 14 graphic representations of pole figures in a density representation;

[0052] Fig 15 is a schematic representation of a comparison between spatial elements of a first lattice plane family distribution, implemented as a first pole figure, with spatial elements of a second lattice plane family distribution, implemented as a second pole figure;

[0053] Fig. 16 is a schematic representation of an evaluation of a symmetry of a first lattice plane distribution, which is implemented in the form of a first pole figure;

[0054] Fig. 17 graphical representations of pole figures of fitted texture measurement sample data after different iteration runs, based on a comparison of a first lattice plane family distribution with a second lattice plane family distribution;

[0055] Fig. 18 graphical representation of pole figures of adjusted texture measurement sample data after several iteration runs, based on an evaluation of a symmetry of several first lattice plane family distributions. Fig. 1 shows a schematic representation of a texture measurement 1 of a measurement sample 2. This can be done, for example, in an electron microscope using electron backscatter diffraction, also referred to as EBSD, where the

[0056] Test sample 2 is irradiated with an electron beam emitted by an electron source 6, and a diffraction pattern is recorded with a diffraction image detector 3, for example a phosphor screen. A theoretical test sample orientation or a theoretical test sample coordinate system RD, TD, ND corresponding thereto can expediently be aligned with a rolling direction RD, a rolling plane normal direction ND, and a transverse direction TD of the test sample 2. As a rule, one axis of the theoretical test sample coordinate system RD, TD, ND is selected parallel to one of these directions. In practice, a deviation from the alignment with the process directions usually arises due to sampling, sample preparation, and / or a measurement setup. Texture test sample data determined during a texture measurement 1 therefore generally refer to a practical test sample orientation or a practical test sample coordinate system. s , e2S , it s , which deviates from the theoretical sample orientation or the theoretical sample coordinate system RD, TD, ND. The practical sample coordinate system ei s , e2 S , e3 s is usually spatially rotated relative to the theoretical sample coordinate system RD, TD, ND. Fig. 2 shows a schematic representation of the sample 2 of Fig. 1, where the practical sample coordinate system is s , e2 S , e3 s and the theoretical sample coordinate system RD, TD, ND are shown. The texture sample data determined during texture determination usually represent crystallographic orientations of crystallites 7 of sample 2, with each crystallite 7 being assigned a crystallite-fixed crystal coordinate system. c , e2 C , e3 cwhich is usually aligned according to a crystallographic orientation of the crystallite 7. As an example, Fig. 2 shows a crystallite 7 with the associated crystal coordinate system ei c , e2 C , e3 c The crystallographic orientation of crystallite 7 can be described by a rotation, which involves a transfer between the crystal coordinate system of a c , e2 C , e3 c and the practical sample coordinate system s , e2 S , e3 s represents.

[0057] The deviation of the practical measurement sample orientation from the theoretical measurement sample orientation or between the corresponding coordinate systems can be at least partially, preferably completely, compensated for using a computer-aided method if texture measurement sample data from a texture measurement of a measurement sample are adapted, in particular rotated, in an alignment procedure of the method, in particular iteratively. The alignment procedure typically comprises a preparation step, a raster step, a comparison step, an orientation error step, and an adjustment step, which are carried out successively, usually in enumerated order. By way of example, the following shows an implementation of the method using texture measurement sample data from a texture measurement of a measurement sample 2 formed from an aluminum alloy, in particular an EN AW-6082 alloy, having a face-centered cubic crystal II structure.The texture measurement was carried out using electron backscatter diffraction with an electron microscope.

[0058] The alignment procedure includes a processing step in which at least one or more first lattice plane family distributions of lattice plane families represented by the texture measurement sample data are specified in the form of pole figures of the lattice plane families, also referred to as first pole figures. The lattice plane families are typically equivalent lattice plane families.

[0059] Fig. 3 to Fig. 5 show exemplary schematic representations of three characteristic lattice planes of different families of lattice planes of a cubic crystal. A respective lattice plane or crystallographic direction can be specified in the art using Miller indices. A respective lattice plane can be represented by a lattice plane normal to the lattice planes. A respective pole figure usually represents a stereographic projection of a layer sphere surface of a layer sphere 5 into an equatorial plane of the layer sphere 5, wherein the test sample 2, in particular its crystallites 7, are imaginarily arranged in the center of the layer sphere 5. This is shown schematically in Fig. 6 as an example for a cubic crystal arranged in the center of the layer sphere. The rolling plane normal direction is usually oriented towards a layer sphere north pole.The pole figure is usually formed by projecting a point of intersection of a respective lattice plane normal on the layer sphere surface into the equatorial plane in the form of poles or representation points, usually by connecting the point of intersection with a layer sphere south pole. Fig. 7 shows a pole figure corresponding to the layer sphere in Fig. 6 with poles or representation points, based on a projection from an upper hemisphere of the layer sphere. The respective pole figure thus forms an arrangement space in which a lattice plane distribution of the lattice plane family, in particular their orientations, is implemented in the form of a spatial arrangement of representation points representing the orientations of the lattice plane family. Fig. 8 to Fig. 10 show first pole figures of test sample 2 for different lattice plane families. Fig. 8 shows a first pole figure for the lattice plane family (001), Fig. 9 a first pole figure for the lattice plane family (110) and Fig.10 a first pole figure for the lattice plane family (111).

[0060] It is advantageous if the alignment procedure has a grid step in which the respective first pole figure is divided into surface elements 8 using a grid 4, wherein an intensity value is assigned to the respective spatial element based on a number, in particular a density, of display points located in the respective spatial element. Fig. 11a shows an example of a graphic representation of a first pole figure with grid 4 drawn in the first pole figure. The grid 4 is formed by grid lines which form radial lines and circumferential circle lines, wherein the radial lines are oriented in the radial direction starting from a center of the first pole figure and the circumferential circle lines form circles with circle centers located in the center of the first pole figure. The radial lines are spaced from one another by equidistant polar angle steps of a polar angle at which the radial lines run.The circumferential circle lines are spaced from one another by equidistant radius increments of a radius that defines the circles of the circumferential circle lines. It is advantageous if the distance between adjacent radial lines or polar angle increments is from 5° to 30°, in particular 5° to 15°, preferably from 5° to 10°. A distance of 10° has proven particularly advantageous. It is advantageous if the distance between adjacent circumferential circle lines or the radius increments is from 5% to 30%, in particular 5% to 15%, preferably from 5% to 10%, of a total radial extension of the first pole figure. A distance of 10% of the total radial extension has proven particularly advantageous.Such an implementation of a grid 4 can in principle be used to subdivide a pole figure with a grid 4 into surface elements 8, in particular within the framework of a grid step, and is in particular not limited to the application example shown here. Fig. 11b alternatively shows a formation of the grid 4 implemented as a projection of a position sphere grid 9, which subdivides a position sphere surface of an upper hemisphere of the position sphere 5 corresponding to the first pole figure into surface segments 10. The position sphere grid 9 is formed by grid lines that form meridians and parallels on the position sphere surface, wherein the meridians are implemented with equidistantly spaced longitudes and the parallels are implemented with equidistantly spaced latitudes. The distance between adjacent longitudes and the distance between adjacent latitudes is usually from 5° to 30°.A spacing of 10° has proven particularly advantageous. The meridians typically run at a constant horizontal angle tp of the position sphere 5. The parallels typically run at a constant vertical angle £ of the position sphere 5. The course of the horizontal angle tp and vertical angle £ is illustrated in the position sphere 5 of Fig. 6. The grid drawn in the first pole figure can then represent a projection of the position sphere grid 9.

[0061] Fig. 12 to Fig. 14 show graphic representations of the first pole figures in a density representation, thus implementing a contour representation. This can be implemented, for example, by dividing the respective pole figure into surface elements 8 using a grid 4 and assigning an intensity value to the respective surface element 8 based on a relative proportion of display points located in the respective spatial element. The respective intensity value can expediently be formed using a ratio of the number of display points in the respective surface element 8 to the total number of display points in the pole figure, in particular averaged over all spatial elements of the pole figure.

[0062] The alignment procedure has a comparison step, wherein in the comparison step the first pole figures are each compared with a second lattice plane family distribution in the form of a second pole figure represented by texture reference data, which corresponds to the respective first pole figure with respect to the lattice plane family and / or a symmetry of the respective first pole figure is evaluated. The respective second pole figure corresponding to the respective first pole figure is usually implemented analogously to the first pole figure, in particular in an analogous density representation formed with a grid. For this purpose, the second pole figure can expediently be divided into surface elements using the same grid 4 as the first pole figure, and an intensity value can be assigned to the respective surface element analogously to the first pole figure. The alignment procedure, in particular the comparison step, specifically the comparison of the first pole figure with the second pole figure orThe evaluation of the symmetry of the first pole figure can be performed with or without a visual representation of a respective pole figure and / or a respective grid. Preferably, this is performed without a visual representation, or the alignment procedure, in particular the comparison of the first pole figure with the second pole figure or the evaluation of the symmetry of the first pole figure, is performed purely computationally.

[0063] Typically, to compare the respective first pole figure with the corresponding second pole figure, spatially corresponding surface elements 8 of the pole figures are compared with each other in terms of their intensity values. Fig. 15 shows a schematic representation of a comparison of surface elements 8 of the first pole figure, in Fig. 15 the left pole figure, with spatially corresponding surface elements 8 of the second pole figure, in Fig. 15 the right pole figure. In a practical manner, surface elements 8 that are spatially correspondingly positioned with respect to the grids 4 subdividing the pole figures can be compared with each other. For this purpose, an absolute value of a difference in the intensity values ​​of the respective corresponding surface elements 8 can be formed, wherein a coverage error is formed by summing the absolute values ​​formed by comparing all respective surface elements 8 of the pole figures.The coverage error may represent an orientation error contribution to form the orientation error.

[0064] Typically, to evaluate the symmetry of the respective first pole figure relative to one another with respect to a, in particular predetermined, axis of symmetry S in the pole figure, spatially corresponding surface elements 8 are compared with one another with respect to their intensity values. The axis of symmetry S can be an axis of the pole figure. Fig. 16 shows a schematic representation of an evaluation of a symmetry of the first pole figure relative to the y-axis of the pole figure as the axis of symmetry S. In practice, surface elements 8 that are spatially axially symmetrically positioned with respect to the grid 4 subdividing the first pole figure with respect to the axis of symmetry S can be compared with one another.For this purpose, an absolute value of a difference in the intensity values ​​of surface elements 8 that spatially correspond to one another with respect to the symmetry axis S can be expediently formed, wherein a symmetry error is formed by summing the absolute values ​​formed by comparing all respective surface elements 8 of the first pole figure that correspond to one another with respect to the symmetry axis S. The symmetry error can represent an orientation error contribution to form the orientation error.

[0065] The alignment procedure includes an orientation error step, wherein an orientation error is calculated by summing the orientation error contributions. The summing can be performed with different weightings of the orientation error contributions, in particular depending on a lattice plane family to which the respective pole figure refers, and / or depending on a type of comparison performed in the comparison step, represented by a comparison between the first pole figure and the second pole figure and / or an evaluation of a symmetry of a first pole figure.

[0066] The alignment procedure includes an adjustment step, wherein the texture measurement sample data is adjusted, in particular spatially rotated, in the adjustment step, so that the orientation error is reduced, in particular minimized. This can advantageously be performed by iteratively adjusting the texture measurement sample data, preferably using a downhill simplex method, while reducing the orientation error. For the adjustment, in particular spatial rotation, of the texture measurement sample data, measurement point angles of respective measurement point data sets of the texture measurement sample data, which measurement point angles correspond to a respective determined crystallographic orientation, are usually changed or adjusted.For iterative adaptation, the alignment procedure can form an iteration loop, wherein each iteration of the iteration loop corresponds to a run through the alignment procedure, wherein texture measurement sample data adapted in the adaptation step are used as input data for the processing step of a subsequent iteration. In the respective iteration, the processing step, the raster step, the comparison step, the orientation error step, and the adaptation step can be run through one after the other in enumeration order. Fig. 17 shows graphical representations of a pole figure of a lattice plane family of the adapted texture measurement sample data after various iteration runs, indicated by an iteration number i of the iteration loop, based on a comparison, in particular as mentioned above, of the first pole figures with the corresponding second pole figures.Figure 17 shows the pole figure for an iteration number i of 0, 36, 41, and 70. Display points or poles of the texture measurement sample data are shown in light gray. For comparison, display points or poles of the corresponding texture reference data are shown in dark gray. The pole figure shown in Figure 17 initially (after 0 iterations) shows a strong deviation between poles of the texture measurement sample data, shown in light gray, and poles of the texture reference data, shown in dark gray. A progressive reduction in the deviation is evident with increasing iteration number i. After 70 iterations, practically no deviation is discernible between the poles of the texture measurement sample data and poles of the texture reference data.

[0067] Fig. 18 shows graphical representations of the first pole figures for the lattice plane families (100), (110), and (111) of adapted texture measurement sample data after running through several iterations based on an evaluation of a symmetry of the first pole figures, in particular as mentioned above. The poles of the adapted texture measurement sample data are shown in light gray. For comparison, the poles of the texture measurement sample data before their adaptation are shown in dark gray in the pole figures. A respective symmetry axis S used for the evaluation of the symmetry is shown as a black line superimposed on the pole figures. For the first pole figures of the lattice plane families (100) and (110), a y-axis of the pole figure was used as an example as the symmetry axis for the evaluation. For the first pole figure of the lattice plane family (111), an x-axis of the pole figure was used as an example as the symmetry axis for the evaluation.It can be seen that the poles of the fitted texture sample data, shown in light grey, show a high symmetry compared to the texture sample data before fitting, shown in dark grey.

[0068] By performing the alignment procedure, in particular as an iteration loop, wherein the preparation step, the raster step, the comparison step, the orientation error step and the adaptation step are carried out successively in the alignment procedure, usually in the specified enumeration order, the texture measurement sample data can be adjusted, in particular rotated, in such a way that a deviation of the practical measurement sample orientation from the theoretical measurement sample orientation is at least partially, preferably substantially, compensated.

Claims

Patent claims 1 . Computer-assisted method for aligning texture measurement sample data of a texture measurement of a measurement sample (2), in particular for at least partially compensating for a deviation of a practical measurement sample orientation from a theoretical measurement sample orientation, wherein texture measurement sample data of a texture measurement (1) of the measurement sample (2) are obtained, characterized in that the method comprises an alignment procedure in which, in particular iteratively: - in a processing step: at least one first lattice plane family distribution of a lattice plane family represented by the texture measurement sample data is specified; - in a comparison step: the first lattice plane distribution is compared with a corresponding second lattice plane distribution represented by texture reference data and / or a symmetry, in particular a spatial symmetry, of the first lattice plane distribution is evaluated; - in an orientation error step: an orientation error is determined based on the comparison or evaluation in the comparison step; - in an adaptation step: the texture measurement sample data are adapted, in particular spatially rotated, so that the orientation error is reduced, in particular minimized.

2. Method according to claim 1, characterized in that the respective lattice plane family distribution of the at least one lattice plane family, in particular its orientation, is implemented in the form of a spatial arrangement of display points representing the orientations of the lattice plane family in an arrangement space, in particular in the form of a pole figure.

3. Method according to claim 2, characterized in that in the comparison step the comparison between the first lattice plane family distribution and the second lattice plane family distribution is carried out based on a respective spatial arrangement, in particular density distribution, of the representation points in the arrangement space, in particular in a respective pole figure, and / or the evaluation of the symmetry of the first lattice plane family distribution is carried out based on a spatial arrangement, in particular density distribution, of the representation points in the arrangement space, in particular the pole figure.

4. Method according to claim 2 or 3, characterized in that in a raster step the respective arrangement space is divided into spatial elements, in particular surface elements (8), using a raster (4), wherein an intensity value is assigned to the respective spatial element based on a number, in particular density, of display points located in the respective spatial element.

5. Method according to one of claims 2 to 4, characterized in that in the comparison step for comparing the first lattice plane family distribution with the corresponding second lattice plane family distribution, spatially corresponding spatial elements of the arrangement spaces of the first lattice plane family distribution and second lattice plane family distribution are compared with each other with regard to their intensity values ​​and / or for evaluating the symmetry of the first lattice plane family distribution with respect to a symmetry axis (S) in the arrangement space, spatially corresponding spatial elements of the arrangement space of the first lattice plane family distribution are compared with each other with regard to their intensity values.

6. The method according to claim 1 or 5, characterized in that the texture measurement sample data comprises a plurality of measurement point data sets, wherein a respective measurement point data set, in particular three, indicates measurement point angles, preferably Euler angles, which indicate a crystallographic orientation with respect to a measurement sample-fixed measurement sample coordinate system (ei s , e2 S , e3 s ) indicate.

7. Method according to one of claims 1 to 6, characterized in that in the processing step a plurality of first lattice plane family distributions of different lattice plane families are specified and in the comparison step the respective first lattice plane family distribution is compared with a corresponding second lattice plane family distribution and / or is evaluated with regard to its, in particular spatial, symmetry.

8. Method according to one of claims 1 to 7, characterized in that based on the comparison carried out in the comparison step and / or the evaluation carried out in the comparison step, an orientation error contribution is formed in each case in order to form the orientation error with the orientation error contribution.

9. Method according to one of claims 1 to 8, characterized in that the texture reference data are texture comparison sample data of a texture measurement (1) of a comparison sample or theoretical texture data.

10. Method according to one of claims 1 to 9, characterized in that texture measurement sample data are adapted with iterative adaptation of the texture measurement sample data, in particular with a derivative-free optimization method, in particular a downhill simplex method, with reduction of the orientation error.

11. Method according to one of claims 1 to 10, characterized in that further texture measurement sample data and / or a texture measurement (1) of a sample, in particular of the measurement sample (2), are adapted based on the adaptations of the texture measurement sample data.

12. Device for data processing, comprising means, in particular at least one processor, which are adapted to carry out the method according to one of claims 1 to 11.

13. Device according to claim 12, characterized in that the device is designed as part of a diffractometer and / or a microscope, in particular an electron microscope, or is coupled to such a device for data transmission.

14. A computer program product comprising instructions which, when executed by a computer, cause the computer to carry out the method according to any one of claims 1 to 13.

15. A computer-readable storage medium on which the computer program product according to claim 14 is stored.

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