1、BRITISH STANDARDBS EN 10247:2007Micrographic examination of the non-metallic inclusion content of steels using standard picturesThe European Standard EN 10247:2007 has the status of a British StandardICS 77.040.99g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g
2、44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 10247:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 May 2007 BSI 2007ISBN 978 0 580 50657 4National forewordThis B
3、ritish Standard was published by BSI. It is the UK implementation of EN 10247:2007. It supersedes DD ENV 10247:1998 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee ISE/72, Methods of physical and metallographic testing.A list of organizations represent
4、ed on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments issu
5、ed since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 10247April 2007ICS 77.040.99 Supersedes ENV 10247:1998 English VersionMicrographic examination of the non-metallic inclusion contentof steels using standard picturesDtermination micrographique de la teneur en
6、 inclusionsnon-mtalliques des aciers laide dimages-typesMetallographische Prfung des Gehaltes nichtmetallischerEinschlsse in Sthlen mit BildreihenThis European Standard was approved by CEN on 13 January 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate th
7、e 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
8、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
9、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 COM
10、MITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 10247:2007: EEN 10247:2007 (E) 2 Conten
11、ts Foreword5 Introduction .6 1 Scope 7 2 Normative references 7 3 Principles7 4 Terms and definitions .8 4.1 General8 4.2 Proximity.9 4.3 Parameters .9 4.4 Classes .10 4.5 Others .10 5 Symbols and abbreviations 11 6 Sampling.13 6.1 General13 6.2 Minimum reduction13 6.3 Size and location of test area
12、 .13 6.4 Number of specimens .14 6.5 Preparation of specimens.14 7 Test method14 7.1 Magnification14 7.2 Field of view .15 7.3 Definition of the pictures of the chart15 7.3.1 Size and Shape.15 7.3.2 Parameters .15 7.3.3 Arrangement of the pictures.15 7.4 Procedure .15 7.4.1 General15 7.4.2 Several i
13、nclusions of mixed sizes in one field .16 7.4.3 Scanning.16 7.4.4 Assessment and evaluation .16 7.4.5 Evaluation of different types of inclusions .17 7.4.6 Default assumptions .17 7.4.7 Recording of results17 8 Types of assessment 17 8.1 Worst inclusion method: method P .17 8.1.1 Principle17 8.1.2 E
14、valuation of PL(worst length)17 8.1.3 Evaluation of Pd(worst diameter)18 8.1.4 Evaluation of Pa(worst area)18 8.2 Worst field method: method M.18 8.2.1 Principle18 8.2.2 Evaluation of Mn(rating according to number) .18 8.2.3 Evaluation of ML(rating according to length)18 8.2.4 Evaluation of Md(ratin
15、g according to diameter)18 8.2.5 Evaluation of Ma(rating according to area)18 8.3 Average field method: method K .19 EN 10247:2007 (E) 3 8.3.1 Principle .19 8.3.2 Scanning of a specimen for average field assessment.19 8.3.3 Evaluation 20 8.3.4 Evaluation of Kn, KLfor elongated and Kn, Kdfor globular
16、 inclusions 20 8.3.5 Evaluation of Knand Ka20 9 Test report21 Annex A (normative) Type of inclusions 34 Annex B (normative) Parameters and assessments to be used if not otherwise specified .36 Annex C (informative) Examples for inclusions of different types37 Annex D (informative) Shape factor 41 An
17、nex E (informative) Examples for magnification.42 Annex F (informative) Details of the eyepiece graticules .44 Annex G (normative) Manufacturing of eyepiece graticule45 G.1 General .45 G.2 Narrow field microscopes 45 G.3 Broad field microscopes 46 Annex H (normative) Calculation basis for the pictur
18、es of the chart49 Annex K (normative) Rules for classification 51 K.1 Definition of classes51 K.2 Classification of length.51 K.3 Classification of width 51 K.4 Classification of diameter.51 K.5 Classification of area 52 Annex L (informative) Comparison of inclusion types in different standards .53
19、Annex M (informative) Worst inclusion assessment.54 Annex N (informative) Worst field assessment56 N.1 General .56 N.2 Evaluation of Mn56 N.3 Evaluation of Mn, MLand Md56 N.4 Evaluation of Mnand Ma57 Annex P (informative) Average field assessment60 P.1 General .60 P.2 Evaluation of Kn, KLand Kd.60 P
20、.3 Evaluation of Knand Ka60 P.4 Restricted values.60 Annex Q (normative) Calculation basis for the assessment69 Q.1 Worst inclusion assessment69 Q.2 Worst field assessment 69 Q.2.1 Calculation of Mn69 Q.2.2 Calculation of ML69 Q.2.3 Calculation of Md70 Q.2.4 Calculation of Ma.70 Q.3 Average field 70
21、 Annex R (normative) Determination of precision and scanning parameters for average field assessment 72 Annex S (informative) Edge Errors correction.75 S.1 General .75 S.2 Field by field measurement 75 Annex T (normative) Calculation of average values of parameters for one class.77 EN 10247:2007 (E)
22、 4 Annex U (normative) Average values of parameters.79 Annex V (informative) Comments of the working group.80 V.1 General80 V.2 Length .80 V.3 Width .80 V.4 Number .80 V.5 Resolution 80 V.6 Area .81 V.7 Description of inclusions81 V.8 Globular particles 82 V.9 Shape factor .82 V.10 Combined inclusio
23、ns 83 V.11 Measuring frame 83 Bibliography 84 EN 10247:2007 (E) 5 Foreword This document (EN 10247:2007) has been prepared by Technical Committee ECISS/TC 2 “Steel - Physico-chemical and non-destructive testing”, the secretariat of which is held by AFNOR. This European Standard shall be given the st
24、atus of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2007, and conflicting national standards shall be withdrawn at the latest by October 2007. Attention is drawn to the possibility that some of the elements of this document may be the s
25、ubject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes ENV 10247:1998. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement
26、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 U
27、nited Kingdom. EN 10247:2007 (E) 6 Introduction This document establishes procedures for the assessment of inclusions in steels, based on their morphology using standard pictures. These procedures include principles that are coherent with physical results obtained from inclusion measurements. The re
28、sults are in physical units: length in m/ mm2, number/ mm2, areas in m2/ mm2. In comparison to other inclusion rating standards, in this standard the order of the classification begins with the length (row index q).These results can be transposed into other standards ratings for comparison purposes.
29、 The conditions of assessments, for instance the rules to scan fields on the specimen, are defined such that there is an optimization between magnification and the number of fields to be assessed. The same precision level is achieved by using the same method in manual evaluation and computer control
30、led measurements. The chart of standard pictures is derived from mathematical principles. The results and their precision may be directly computed from field assessments. EN 10247:2007 (E) 7 1 Scope This European Standard defines a method of microscopic non-metallic inclusion assessment using pictur
31、e charts. The method does not apply to particles of a length less than 3,0 m or a width smaller than 2,0 m. Defined by a product standard or agreement between the involved parties for certain special products, inclusions with a width below 2,0 m can only be evaluated according to their length. Elong
32、ated inclusions with a length above 1 410 m are counted separately and are beyond the upper application limit of this standard. Globular inclusions with a diameter of 3,0 m and above are included in the assessment. It is assumed, if particles are elongated or if there are stringers of particles, tha
33、t they are parallel to each other. Other arrangements are not covered by this standard. This European Standard applies to samples with a microscopic precipitation approaching random distribution. From the data of measurements obtained by this method, evaluation according to other standards can be es
34、tablished. This European Standard does not apply to free cutting steels. NOTE The basic principle of this European Standard allows the determination of non-metallic inclusion content by image analysis techniques. 2 Normative references The following referenced documents are indispensable for the app
35、lication 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 ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:
36、2005) 3 Principles This method consists of a comparison between inclusions observed in a field of view with chart pictures. The chart pictures defined by this European Standard are based on the shape of inclusions and for each shape on length, width and area, for columns 1 to 10 and number for colum
37、n 11. This standard employs an ellipse as a basic shape with the circle as a special case of an ellipse (see Figure 1a). Inclusions with a shape like a rectangle or square are treated as ellipses or circles as their areas are not significantly different for the purpose of this method. The pictures a
38、re arranged in rows and columns. The length changes from row to row, the shape factor changes from column to column. This standard is principally concerned with the morphology and arrangement of inclusions. It does not provide information relevant to crystal structure or chemical constitution of mea
39、sured inclusions. General practice usually requires a differentiation between inclusions of different chemical composition. The definition of the types should be defined by the product standards. Should no standard be available, then the definition of characteristic morphologies shall be, by agreeme
40、nt, between the involved parties. To make description easier, a tree of specific terms is given in Annex A, Figure A.1. The chart pictures represent the upper limits of classes. The length Lxis classified in row q if: qx1-qLLL 3 w2then the particles w1and w2are treated separately. For an example see
41、 Figure 2e. Some examples for inclusions are given in Figure 2f EN 10247:2007 (E) 9 4.1.3 stringer arrangement of at least 3 particles, normally aligned, forming an inclusion (see Figures 2b, 2f), For examples see Annex C and Figure 2f 4.1.4 test area area on the polished surface of the specimen to
42、be evaluated NOTE In general, the size of the test area is 200 mm2. 4.2 Proximity 4.2.1 distances between particles distance e between the particles in the direction of main deformation and distance t in the direction perpendicular to it (see Figure 2a) 4.2.2 distance between stringers similar to th
43、at for the distance between particles (see Figure 2b) 4.2.3 scattered random arrangement of particles. NOTE For example see Annex C. This is defined in one field of view 4.3 Parameters 4.3.1 length dimension of an inclusion in the main direction of deformation, always assumed to be greater than the
44、width 4.3.2 diameter maximum dimension of inclusion classified according to column 6 (globular inclusion) 4.3.3 width Maximum width perpendicular to the direction of principal deformation. This is the width of the ellipse inscribed to the confining rectangle and having the same length as the inclusi
45、on. For manual evaluation this value can only be estimated. The width is the maximum width perpendicular to the direction of principal deformation for inclusions with only one particle. The width w of an inclusion with 2 particles is given by the largest particle (see Figure 2a). Width of a stringer
46、 (see Figure 1b): The width of a stringer is defined as the width of an ellipse inscribed to the confining rectangle and having the same length as the stringer Width of an inclusion out of several stringers (see Figure 2b). The distance t between two stringers is defined as the shortest distance bet
47、ween the confining rectangles in a transverse direction. The distance e is defined as the shortest distance between the confining rectangles in a machine direction. Case a) for 0 e 40 m, t 10 m: is the width of an inclusion out of two stringers defined as the width of the widest stringer. (wtotal= w
48、1, w1 w2) (see Figure 2b, a). EN 10247:2007 (E) 10 Case b) for e w1 w = w2(1 inclusion) if e 40 m or t 10 m, L1= L1w1= w1L2 = L2w2 = w2(2 inclusions) Figure 2a Definition of inclusions composed by single particles EN 10247:2007 (E) 25 w = width of an ellipse inscribed to the confining rectangle and
49、having the same length as the stringer n = number of particles if all t 10 m and if e1to e17all 40 m L = L1+ e1+ L2+ e2e17+ L18 ()=+=1n1xxxneLLL Figure 2b Definition of stringers a) b) c) Key w1 w2w1 w2w2* = w2+ t2+ w3w2* = w4 w1 w2 w30 e5 40 m t 10 m wtotal= w1e53 m w1 2 m L33 m w2 2 m if e 40 m 2 inclusions Figure 2c Definition of inclusions: Particles below minimum size are not taken into account EN 10247:2007 (E) 27 Key 1 spherical or rectangular particle 2 elongated particle ( ) number of the example Figure 2d In
