SIST EN 15305:2009

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Neporušitveno preskušanje - Preskusna metoda analize zaostalih napetosti z uklonom rentgenskih žarkovZerstörungsfreie Prüfung - Röntgendiffraktometrisches Prüfverfahren zur Ermittlung der EigenspannungenEssais non-destructifs - Méthode d'essai pour l'analyse des contraintes résiduelles par diffraction des rayons XNon-destructive Testing - Test Method for Residual Stress analysis by X-ray Diffraction19.100Neporušitveno preskušanjeNon-destructive testingICS:Ta slovenski standard je istoveten z:EN 15305:2008SIST EN 15305:2009en,fr,de01-april-2009SIST EN 15305:2009SLOVENSKI
STANDARD



SIST EN 15305:2009



EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 15305August 2008ICS 19.100 English VersionNon-destructive Testing - Test Method for Residual Stressanalysis by X-ray DiffractionEssais non-destructifs - Méthode d'essai pour l'analyse descontraintes résiduelles par diffraction des rayons XZerstörungsfreie Prüfung - RöntgendiffraktometrischesPrüfverfahren zur Ermittlung der EigenspannungenThis European Standard was approved by CEN on 4 July 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15305:2008: ESIST EN 15305:2009



EN 15305:2008 (E) 2 Contents Page Foreword.5 Introduction.6 1 Scope.7 2 Normative references.7 3 Terms, definitions and symbols.8 3.1 Terms and definitions.8 3.2 Symbols and abbreviations.8 4 Principles.10 4.1 General principles of the measurement.10 4.2 Biaxial stress analysis.12 4.3 Triaxial stress analysis.13 5 Specimen.14 5.1 Material characteristics.14 5.1.1 General.14 5.1.2 Shape, dimensions and weight.15 5.1.3 Specimen composition/homogeneity.15 5.1.4 Grain size and diffracting domains.16 5.1.5 Specimen X-ray transparency.16 5.1.6 Coatings and thin layers.16 5.2 Preparation of specimen.17 5.2.1 Surface preparation.17 5.2.2 Stress depth profiling.17 5.2.3 Large specimen or complex geometry.17 6 Equipment.17 6.1 General.17 6.2 Choice of equipment.18 6.2.1 General.18 6.2.2 The ωωωω-method.19 6.2.3 The χχχχ-method.20 6.2.4 The modified χχχχ-method.21 6.2.5 Other geometries.21 6.3 Choice of radiation.21 6.4 Choice of the detector.23 6.5 Performance of the equipment.24 6.5.1 Alignment.24 6.5.2 Performance of the goniometer.24 6.6 Qualification and verification of the equipment.24 6.6.1 General.24 6.6.2 Qualification.24 6.6.3 Verification of the performance of the qualified equipment.26 7 Experimental Method.27 7.1 General.27 7.2 Specimen positioning.27 7.3 Diffraction conditions.28 7.4 Data collection.29 8 Treatment of the data.30 8.1 General.30 8.2 Treatment of the diffraction data.30 8.2.1 General.30 SIST EN 15305:2009



EN 15305:2008 (E) 3 8.2.2 Intensity corrections.30 8.2.3 Determination of the diffraction line position.31 8.2.4 Correction on the diffraction line position.32 8.3 Stress calculation.32 8.3.1 Calculation of strains and stresses.32 8.3.2 Errors and uncertainties [16], [17].33 8.4 Critical assessment of the results.34 8.4.1 General.34 8.4.2 Visual inspection.34 8.4.3 Quantitative inspection.34 9 Report.35 10 Experimental determination of XECs.36 10.1 Introduction.36 10.2 Loading device.37 10.3 Specimen.37 10.4 Loading device calibration and specimen accommodation.38 10.5 Diffractometer measurements.38 10.6 Calculation of XECs.38 11 Reference specimens.39 11.1 Introduction.39 11.2 Stress-free reference specimen.39 11.2.1 General.39 11.2.2 Preparation of the stress-free specimen.39 11.2.3 Method of measurement.40 11.3 Stress-reference specimen.40 11.3.1 Laboratory qualified (LQ) stress-reference specimen.40 11.3.2 Inter-laboratory qualified (ILQ) stress-reference specimen.41 12 Limiting cases.41 12.1 Introduction.41 12.2 Presence of a subsurface stress gradient.42 12.3 Surface stress gradient.42 12.4 Surface roughness.42 12.5 Non-flat surfaces.42 12.6 Effects of specimen microstructure.43 12.6.1 Textured materials.43 12.6.2 Multiphase materials.43 12.7 Broad diffraction lines.44 Annex A (informative)
Schematic representation of the European XRPD Standardisation Project.46 Annex B (informative)
Sources of Residual Stress.47 B.1 General.47 B.2 Mechanical processes.47 B.3 Thermal processes.47 B.4 Chemical processes.47 Annex C (normative)
Determination of the stress state - General Procedure.48 C.1 General.48 C.2 Using the exact definition of the deformation.49 C.2.1 General.49 C.2.2 Determination of the stress tensor components.49 C.2.3 Determination of θθθθ and d0.50 C.3 Using an approximation of the definition of the deformation.50 C.3.1 General.50 C.3.2 Determination of the stress tensor components.51 C.3.3 Determination of θθθθ0 and d0.51 Annex D (informative)
Recent developments.52 D.1 Stress measurement using two-dimensional diffraction data.52 D.2 Depth resolved evaluation of near surface residual stress - The Scattering Vector Method.54 SIST EN 15305:2009



EN 15305:2008 (E) 4 D.3 Accuracy improvement through the use of equilibrium conditions for determination of stress profile.55 Annex E (informative)
Details of treatment of the measured data.56 E.1 Intensity correction on the scan.56 E.1.1 General.56 E.1.2 Divergence slit conversion.56 E.1.3 Absorption correction.57 E.1.4 Background correction.58 E.1.5 Lorentz-polarisation correction.58 E.1.6 K-Alpha2 stripping.59 E.2 Diffraction line position determination.59 E.2.1 Centre of Gravity methods.59 E.2.2 Parabola Fit.60 E.2.3 Profile Function Fit.60 E.2.4 Middle of width at x% height method.61 E.2.5 Cross-correlation method.61 E.3 Correction on the diffraction line position.61 E.3.1 General.61 E.3.2 Remaining misalignments.61 E.3.3 Transparency correction.62 Annex F (informative)
General description of acquisition methods.64 F.1 Introduction.64 F.2 Definitions.64 F.3 Description of the various acquisition methods.67 F.3.1 General method.67 F.3.2 Omega (ωωωω) method.68 F.3.3 Chi (χχχχ) method.69 F.3.4 Combined tilt method (also called scattering vector method).71 F.3.5 Modified chi method.73 F.3.6 Low incidence method.76 F.3.7 Modified omega method.77 F.3.8 Use of a 2D (area) detector.78 F.4 Choice of ΦΦΦΦ and ΨΨΨΨ angles.79 F.5 The stereographic projection.80 Annex G (informative)
Normal Stress Measurement Procedure" and "Dedicated Stress Measurement Procedure.82 G.1 Introduction.82 G.2 General.82 G.2.1 Introduction.82 G.2.2 Normal stress measurement procedure for a single specimen.82 G.2.3 Dedicated Stress Measurement Procedure for very similar specimens.82 Bibliography.84
SIST EN 15305:2009



EN 15305:2008 (E) 5 Foreword This document (EN 15305:2008) has been prepared by Technical Committee CEN/TC 138 “Non-destructive testing”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2009, and conflicting national standards shall be withdrawn at the latest by February 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This European Standard about “Non destructive testing - X-ray diffraction from polycrystalline and amorphous material” is composed of:  EN 13925-1, General principles;  EN 13925-2, Procedures;  EN 13925-3, Instruments;  EN 1330-11, Non-destructive testing - Terminology - Terms used in X-ray diffraction from polycrystalline and amorphous materials In order to explain the relationship between the topics described in the different standards, a diagram illustrating typical operation involved in XRPD is given in Annex A. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. SIST EN 15305:2009



EN 15305:2008 (E) 6 Introduction Residual strains in crystalline materials may be determined by X-ray diffraction analysis. Assuming linear elastic distortions, the related residual stresses are calculated.
In this document the principles of the measure procedure and the analysis technique are described. SIST EN 15305:2009



EN 15305:2008 (E) 7 1 Scope
This European Standard describes the test method for the determination of macroscopic residual or applied stresses non-destructively by X-ray diffraction analysis in the near-surface region of a polycrystalline specimen or component.
All materials with a sufficient degree of crystallinity can be analysed, but limitations may arise in the following cases (brief indications are given in Clause 12):
 Stress gradients;  Lattice constants gradient ;  Surface roughness;  Non-flat surfaces (see 5.1.2);  Highly textured materials;  Coarse grained material (see 5.1.4);  Multiphase materials;  Overlapping diffraction lines;  Broad diffraction lines.
The specific procedures developed for the determination of residual stresses in the cases listed above are not included in this document.
The method described is based on the angular dispersive technique with reflection geometry as defined by EN 13925-1.
The recommendations in this document are meant for stress analysis where only the diffraction line shift is determined.
This European Standard does not cover methods for residual stress analyses based on synchrotron X-ray radiation and it does not exhaustively consider all possible areas of application.
Radiation Protection. Exposure of any part of the human body to X-rays can be injurious to health. It is therefore essential that whenever X-ray equipment is used, adequate precautions should be taken to protect the operator and any other person in the vicinity. Recommended practice for radiation protection as well as limits for the levels of X-radiation exposure are those established by national legislation in each country. If there are no official regulations or recommendations in a country, the latest recommendations of the International Commission on Radiological Protection should be applied. 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. EN 13925-1:2003, Non-destructive testing – X-ray diffraction from polycrystalline and amorphous material – Part 1: General principles
SIST EN 15305:2009



EN 15305:2008 (E) 8 EN 13925-2:2003, Non-destructive testing – X-ray diffraction from polycrystalline and amorphous materials – Part 2: Procedures. EN 13925-3:2005, Non-destructive testing – X-ray diffraction from polycrystalline and amorphous materials – Part 3: Instruments ISO 5725-1, Accuracy (trueness and precision) of measurement methods and results – Part 1: General principles and definitions ISO 5725-2, Accuracy (trueness and precision) of measurement methods and results – Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method 3 Terms, definitions and symbols
For the purposes of this document, the following term, definition and symbols apply 3.1 Terms and definitions
3.1.1 Residual stress self-equilibrating internal stresses existing in a free body which has no external forces or constraints acting on its boundary
3.2 Symbols and abbreviations  2θ
The diffraction angle; this is the angle between the incident and diffracted X-ray beams.  θ
The Bragg angle; this is the angle between the diffracting lattice planes and the incident beam.  ω
The angle between the incident X-ray beam and the specimen surface at χ = 0.  φ The angle between a fixed direction in the plane of the specimen and the projection in that plane of the normal to the diffracting lattice planes.
 ψ
The angle between the normal of the specimen and the normal of the diffracting lattice planes.  χ
The angle χ rotates in the plane perpendicular to that containing ω and 2θ; the rotation axis of χ is
orientated perpendicular to both
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