1、April 2013 Translation by DIN-Sprachendienst.English price group 20No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、71.040.50!*“7615959www.din.deDDIN ISO 24173Microbeam analysis Guidelines for orientation measurement using electron backscatterdiffraction (ISO 24713:2009),English translation of DIN ISO 24173:2013-04Mikrobereichsanalyse Leitfaden zur Messung der Orientierung mit Elektronenrckstreudiffraktometrie(IS
3、O 24173:2009),Englische bersetzung von DIN ISO 24173:2013-04Analyse par microfaisceaux Lignes directrices pour la mesure dorientation par diffraction dlectrons rtrodiffuss(ISO 24173:2009),Traduction anglaise de DIN ISO 24173:2013-04www.beuth.deDocument comprises pagesIn case of doubt, the German-lan
4、guage original shall be considered authoritative.4804.13DIN ISO 24173:2013-04 2 A comma is used as the decimal marker. Contents Page National foreword .4 National Annex NA (informative) Bibliography 4 Introduction .5 1 Scope 6 2 Normative references 6 3 Terms and definitions .6 4 Equipment for EBSD
5、12 5 Operating conditions . 13 5.1 Specimen preparation 13 5.2 Specimen alignment. 14 5.3 Common steps in collecting an EBSP . 14 5.3.1 Setting the microscope operating conditions . 14 5.3.2 Detector and working distances . 14 5.3.3 Camera integration/exposure time . 15 5.3.4 Binning 15 5.3.5 EBSP a
6、veraging 16 5.3.6 EBSP background correction/EBSP signal correction 16 5.3.7 Band detection 17 6 Calibrations required for indexing of EBSPs 18 7 Analytical procedure 21 7.1 Pre-test preparation . 21 7.2 Operating conditions . 22 7.3 Equipment stability check . 22 7.4 EBSD analysis 22 8 Measurement
7、uncertainty 22 8.1 General 22 8.2 Uncertainty of crystal orientation measurement 22 8.3 Absolute orientation. 23 8.4 Relative orientation 23 9 Reporting the results . 23 Annex A (informative) Principle of EBSD. 24 Annex B (normative) Specimen preparation for EBSD 25 B.1 General 25 B.2 Cutting . 25 B
8、.3 Mounting . 25 B.4 Grinding . 25 B.5 Polishing . 26 B.6 Etching 27 B.7 Ion beam techniques 28 B.8 Conductive coating 2230 DIN ISO 24173:2013-04 3 Annex C (informative) Brief introduction to crystallography and EBSP indexing, and other information useful for EBSD 31 C.1 General . 31 C.2 Symmetry .
9、31 C.3 The unit cell . 32 C.4 Crystal directions 32 C.5 Crystal planes 33 C.6 Crystal systems . 33 C.7 Laue groups . 34 C.8 Bravais lattices 35 C.9 Manual indexing of a cubic EBSP . 36 C.10 Examples of indexed cubic EBSPs . 37 C.11 Hexagonal indices . 38 C.12 Useful formulae and information . 40 C.1
10、2.1 Symbols . 40 C.12.2 Electron wavelength as a function of accelerating voltage 41 C.12.3 Interplanar spacing for plane (hkl) 41 C.12.4 Unit cell volume . 41 C.12.5 Angle between two planes (h1k1l1) and (h2k2l2) . 42 C.12.6 To find the zone uvw that is perpendicular to plane (hkl) . 42 C.12.7 Rela
11、tionships between zones and planes 42 C.12.8 Conditions for a Kikuchi band to be visible . 42 C.12.9 Cubic interzonal and interplanar angles . 44 C.12.10 Cristallographic information for selected cubic phases . 45 C.12.11 Cristallographic information for selected hexagonal, tetragonal and orthorhomb
12、ic phases . 45 C.12.12 Cubic coincidence site lattice (CSL) misorientation relationships . 46 Bibliography 47 DIN ISO 24173:2013-04 4 National foreword This document (ISO 24173:2009) has been prepared by Technical Committee ISO/TC 202 “Microbeam analysis” (Secretariat: SAC, China). The responsible G
13、erman body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Working Committee NA 062-08-18 AA Elektronenmikroskopie und Mikrobereichsanalyse. Attention is drawn to the possibility that some of the elements of this document may be the subject
14、 of patent rights. DIN and/or DKE shall not be held responsible for identifying any or all such patent rights. In addition to the legal units of measurement, this standard also uses the unit “” (“ngstrm”). It should, however, be noted that the Gesetz ber Einheiten im Messwesen (German Law on units i
15、n metrology) prohibits the use of the unit “” for official and commercial purposes in Germany. The indication of this unit solely serves to facilitate the communication with those countries where this unit is used (import-export business). Conversion: 1 = 1010m = 107mm = 104m = 0,1 nm = 100 pm The D
16、IN Standards corresponding to the International Standards referred to in this document are as follows: ISO/IEC 17025 DIN EN ISO/IEC 17025 ISO/IEC Guide 98-3 DIN V ENV 13005 National Annex NA (informative) Bibliography DIN EN ISO/IEC 17025, General requirements for the competence of testing and calib
17、ration laboratories DIN V ENV 13005, Guide to the expression of uncertainty in measurement Introduction Electron backscatter diffraction (EBSD) is a technique that is used with a scanning electron microscope (SEM), a combined SEM-FIB (focussed-ion beam) microscope or an electron probe microanalyser
18、(EPMA) to measure and map local crystallography in crystalline specimens1,2. Electron backscatter patterns (EBSPs) are formed when a stationary electron beam strikes the surface of a steeply inclined specimen, which is usually tilted at 70 from normal to the electron beam. EBSPs are imaged via an EB
19、SD detector, which comprises a scintillator (such as a phosphor screen or a YAG single crystal) and a low-light-level camera (normally a charge-coupled device, CCD). Patterns are occasionally imaged directly on photographic film. By analysing the EBSPs, it is possible to measure the orientation of t
20、he crystal lattice and, in some cases, to identify also the phase of the small volume of crystal under the electron beam. EBSD is a surface diffraction effect where the signal arises from a depth of just a few tens of nanometres, so careful specimen preparation is essential for successful applicatio
21、n of the technique3. In a conventional SEM with a tungsten filament, a spatial resolution of about 0,25 m can be achieved; however, with a field-emission gun SEM (FEG-SEM), the resolution limit is 10 nm to 50 nm, although the value is strongly dependent on both the material being examined and on the
22、 instrument operating parameters. Orientation measurements in test specimens can be carried out with an accuracy of 0,5. By scanning the electron beam over a region of the specimen surface whilst simultaneously acquiring and analysing EBSPs, it is possible to produce maps that show the spatial varia
23、tion of orientation, phase, EBSP quality and other related measures. These data can be used for quantitative microstructural analysis to measure, for example, the average grain size (and in some cases the size distribution), the crystallographic texture (distribution of orientations) or the amount o
24、f boundaries with special characteristics (e.g. twin boundaries). EBSD can provide three-dimensional microstructural characterization by its use in combination with an accurate serial sectioning technique, such as focussed-ion beam milling4. It is strongly recommended that EBSD users be well acquain
25、ted with both the principles of crystallography and the various methods for representing orientations (both of which are described in the existing literature in this field) in order to make best use of the EBSD technique and the data produced5,6. Microbeam analysis Guidelines for orientation measure
26、ment using electron backscatter diffraction DIN ISO 24173:2013-04 5 IMPORTANT The electronic file of this document contains colours which are considered to be useful for the correct understanding of the document. Users should therefore consider printing this document using a colour printer. 1 Scope
27、This International Standard gives advice on how to generate reliable and reproducible crystallographic orientation measurements using electron backscatter diffraction (EBSD). It addresses the requirements for specimen preparation, instrument configuration, instrument calibration and data acquisition
28、. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO/IEC 17025, General r
29、equirements for the competence of testing and calibration laboratories ISO/IEC Guide 98-3, Uncertainty of measurement Part 3: Guide to the expression of uncertainty in measurement (GUM:1995) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 cry
30、stal entity consisting of a regular, repeated arrangement of atoms in space and usually described by a space group, a crystal system, unit cell parameters (including the lengths and angles between the unit cell axes) and the positions of the atoms inside the unit cell7,8NOTE 1 For example, an alumin
31、ium crystal can be represented by a cube (unit cell) of length 0,404 94 nm along each edge and with atoms at the corners and centres of the cube faces. NOTE 2 Simulations of the atomic arrangement in a small (4 4 4 unit cells) aluminium crystal, as viewed along the 1 0 0, 1 1 1 and 1 1 0 directions,
32、 are shown in Figure 1, together with the associated spherical Kikuchi patterns for each crystal orientation. The 4-fold, 3-fold and 2-fold crystal symmetries are easily seen, as are the mirror planes. NOTE 3 For those unfamiliar with crystallography, it is recommended that a standard textbook be co
33、nsulted (see for example References 7, 8 and 9). NOTE 4 Annex C contains a brief introduction to crystallography and a guide to the indexing of EBSPs for materials with cubic crystal symmetry. DIN ISO 24173:2013-04 6Figure 1 Simulations of a small aluminium crystal (top) as viewed along the 1 0 0, 1
34、 1 1 and 1 1 0 directions, with their associated spherical Kikuchi patterns (bottom). The symmetry is clearly shown. 3.2 crystal plane plane, usually denoted as (h k l), representing the intersection of a plane with the a-, b- and c-axes of the unit cell at distances of 1/h, 1/k and 1/l, where h, k,
35、 and l are integers NOTE 1 The integers h, k, and l are usually referred to as the Miller indices of a crystal plane. NOTE 2 See Annex C for more information. 3.3 crystal direction direction, usually denoted as u v w, representing a vector direction in multiples of the basis vectors describing the a
36、, b and c crystal axes NOTE See Annex C for more information. 3.4 crystal unit cell cell which is repeated (infinitely) to build up the crystal NOTE It is usually defined by three lengths, a, b and c, and three angles, , and . The lengths are usually given in ngstrms or nanometres and the angles in
37、degrees. 3.5 crystallographic orientation alignment of the crystal coordinate system (for example, 1 0 0, 0 1 0, 0 0 1 for a cubic crystal) in relation to the specimen coordinate system NOTE The specimen coordinate system can be denoted as X, Y, Z. When EBSD is applied to the study of rolled materia
38、ls, it is often denoted as RD, TD, ND RD = reference (or rolling) direction, TD = transverse direction and ND = normal direction. DIN ISO 24173:2013-04 7 3.6 EBSD detector detector used to capture the electron backscatter pattern and convert it to an image visible on the display device (computer scr
39、een) via a video-camera, which is commonly a high-sensitivity charged-coupled device (CCD) NOTE See also 3.21. 3.7 electron backscatter diffraction EBSD diffraction process that arises between the backscattered electrons and the atomic planes of a highly tilted crystalline specimen when illuminated
40、by a stationary incident electron beam NOTE Commonly used alternative terms for EBSD are “EBSP” (or more usually the “EBSP technique”) (see 3.8), “BKD” (backscattered Kikuchi diffraction), “BKED” (backscattered Kikuchi electron diffraction) and “BKDP” (backscattered Kikuchi diffraction pattern). 3.8
41、 electron backscatter pattern EBSP intersecting array of quasi-linear features, known as Kikuchi bands (see Figure 2), produced by electron backscatter diffraction and recorded using a suitable detector, for example observed on a phosphorescent screen or, less commonly, on photographic film Figure 2
42、 Examples of EBSPs showing arrays of overlapping Kikuchi bands 3.9 EBSD grain region, with similar orientation, delineated by boundaries at which the misorientation between neighbouring measurement points is greater than a defined critical value which depends on the application103.10 EBSD spatial re
43、solution minimum distance between two points in different grains (separated by a sharp boundary) that produces two distinctly different EBSPs that can be correctly indexed using an EBSD system NOTE An example is shown in Figure 3 where the electron beam has been passed over a boundary in a meteorite
44、 specimen. Two distinct and different EBSP orientations can be seen in the far-left and far-right images, but the central EBSP is a mixture of the two. Modern indexing algorithms frequently allow solution of such overlapping patterns, which leads to an effective improvement in the EBSD spatial resol
45、ution. DIN ISO 24173:2013-04 8Figure 3 Examples of EBSPs from either side (far left and far right) and on a grain boundary (centre) (Note that these images were taken at 30 nm spacings and the centre EBSP is a combination of the other two) 3.11 Euler angles set of three rotations for representing th
46、e orientation of a crystal relative to a set of specimen axes NOTE The Bunge convention (rotations about the Z, X and Z directions) is most commonly used for describing EBSD data. The Euler angles give the rotation needed to bring the specimen coordinate system into coincidence with the crystal coor
47、dinate system. It should be noted that there are equivalent sets of Euler angles, depending on crystal symmetry6. 3.12 Hough transform mathematical technique of image processing which allows the automated detection of features of a particular shape within an image NOTE In EBSD, a linear Hough transf
48、orm is used to identify the position and orientation of the Kikuchi bands in each EBSP, which enables the EBSP to be indexed. Each Kikuchi band is identified as a maximum in Hough space. The Hough transform is essentially a special case of the Radon transform. Generally, the Hough transform is for b
49、inary images, and the Radon transform is for grey-level images11,12. See 5.3.7 for more details. 3.13 indexing process of identifying the crystallographic orientation corresponding to the features in a given EBSP, for example determining which crystal planes correspond to the detected Kikuchi bands or which crystal direc
