1、August 2014 Translation by DIN-Sprachendienst.English price group 11No 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、 77.040.10!%:1.“2231411www.din.deDDIN EN ISO 10275Metallic materials Sheet and strip Determination of tensile strain hardening exponent (ISO 10275:2007);English version EN ISO 10275:2014,English translation of DIN EN ISO 10275:2014-08Metallische Werkstoffe Blech und Band Bestimmung des Verfestigungs
3、exponenten im Zugversuch (ISO 10275:2007);Englische Fassung EN ISO 10275:2014,Englische bersetzung von DIN EN ISO 10275:2014-08Matriaux mtalliques Tles et bandes Dtermination du coefficient dcrouissage en traction (ISO 10275:2007);Version anglaise EN ISO 10275:2014,Traduction anglaise de DIN EN ISO
4、10275:2014-08SupersedesDIN ISO 10275:2009-06www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document comprises 18 pages 08.14 DIN EN ISO 10275:2014-08 2 A comma is used as the decimal marker. National foreword This document (EN ISO 10275:2014) has been pr
5、epared by Technical Committee ISO/TC 164 “Mechanical testing of metals”, Subcommittee SC 2 “Ductility testing” (Secretariat: JISC, Japan) and has been taken over without any modification as EN ISO 10275 by Technical Committee ECISS/TC 101 “Test methods for steel (other than chemical analysis)” (Secr
6、etariat: AFNOR, France). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (DIN Standards Committee Materials Testing), Working Committee NA 062-01-42 AA Zug- und Duktilittsprfung fr Metalle. Users of this standard should take note of the following: This
7、standard describes the determination of the tensile strain hardening exponent at room temperature. The equations for calculating the true stress (Equation 3), the true plastic strain (Equation 4) and the true cross-section area (Equation 5) are based on the assumption that the parallel length of the
8、 test piece in the area under evaluation remains prismatic and that there is no formation of a neck or waist. Depending on the material/material condition, waisting along the parallel length of test pieces may occur long before a neck actually is formed. This effect is, in general, still more pronou
9、nced at elevated temperatures. For this reason it should be noted that the unrestricted application of the method described in this standard is not possible at elevated temperatures. Besides the following two points that, according to the standard, are required to be satisfied when considering the l
10、ower limit of the plastic (engineering) strain for the regression method: the final testing rate needs to have been reached (this being the rate after the yield/proof strength and yield strength elongation have been determined, i.e. the rate at which the tensile test is generally continued and at wh
11、ich Rmand Ag, for instance, are determined; the plastic (engineering) strain needs to be greater than the yield strength elongation; the following aspect should also be taken into account: the measuring data density needs to be constant, as is the case with the upper limit; the reason being that as
12、the data density is initially higher in the tensile test (i.e. in the elastic region and the region in which the yield strength is determined), the results would otherwise be weighted in favour of the determined range close to the lower limit. According to Table 1 (in analogy with the English refere
13、nce version), epdefines the plastic (engineering) strain at which the tensile strain hardening exponent is determined using the manual evaluation method given in Subclause 7.6. The explanation in parentheses (“single data point method”) is also expressed as the “manual method”. ISO 6892:1998 cited i
14、n this document has been replaced by ISO 6892-1:2009 and adopted as DIN EN ISO 6892-1:2009-12. The DIN Standards corresponding to the International Standards referred to in Clause 2 of this standard are as follows: ISO 6892 DIN EN ISO 6892-1 ISO 7500-1 DIN EN ISO 7500-1 ISO 9513 DIN EN ISO 9513 ISO
15、10113 DIN EN ISO 10113 DIN EN ISO 10275:2014-08 3 Amendments This standard differs from DIN ISO 10275:2009-06 as follows: a) International Standard ISO 10275 has been adopted as European Standard EN ISO 10275; b) the standard has been editorially revised. Previous editions DIN ISO 10275: 2009-06 DIN
16、 EN ISO 10275:2014-08 4 National Annex NA (informative) Bibliography DIN EN ISO 6892-1, Metallic materials Tensile testing Part 1: Method of test at room temperature DIN EN ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Ve
17、rification and calibration of the force-measuring system DIN EN ISO 9513, Metallic materials Calibration of extensometer systems used in uniaxial testing DIN EN ISO 10113, Metallic materials Sheet and strip Determination of plastic strain ratio EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN IS
18、O 10275 June 2014 ICS 77.040.10 English Version Metallic materials - Sheet and strip - Determination of tensile strain hardening exponent (ISO 10275:2007) Matriaux mtalliques - Tles et bandes - Dtermination du coefficient dcrouissage en traction (ISO 10275:2007) Metallische Werkstoffe - Blech und Ba
19、nd - Bestimmung des Verfestigungsexponenten im Zugversuch (ISO 10275:2007)This European Standard was approved by CEN on 6 June 2014. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national sta
20、ndard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in
21、any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Re
22、public, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPE
23、AN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 10275:2014 EEN
24、 ISO 10275:2014 (E) 2 Contents Page Foreword . 3 Introduction . 4 1 Scope 5 2 Normative references 5 3 Symbols and designations . 5 4 Principle . 7 5 Test equipment 7 6 Test pieces . 7 7 Procedure . 7 8 Test report 12 Annex A (informative) International comparison of symbols used in the determinatio
25、n of the tensile strain hardening exponent 13 Bibliography 14 DIN EN ISO 10275:2014-08EN ISO 10275:2014 (E) 3 Foreword The text of ISO 10275:2007 has been prepared by Technical Committee ISO/TC 164 “Mechanical testing 10275:2014 by Technical Committee ECISS/TC 101 “Test methods for steel (other than
26、 chemical analysis)” the secretariat of which is held by AFNOR. EN ISOof metals” of the International Organization for Standardization (ISO) and has been taken over asThis European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement
27、, at the latest by December 2014, and conflicting national standards shall be withdrawn at the latest by December 2014. 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 identifyi
28、ng any or all such patent rights. 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, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav
29、Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 10275:2007 has bee
30、n approved by CEN as EN ISO 10275:2014 without any modification. DIN EN ISO 10275:2014-08Introduction In the former version of this International Standard, for the calculation of the true strain, the elastic strain did not need to be subtracted from the total strain if it was lower than 10 % of the
31、total strain. In this new International Standard, the elastic strain is subtracted from the total strain for calculation of the true strain, which is now referred to as “true plastic strain”. DIN EN ISO 10275:2014-084EN ISO 10275:2014 (E) 1 Scope This International Standard specifies a method for de
32、termining the tensile strain hardening exponent n of flat products (sheet and strip) made of metallic materials. The method is valid only for that part of the stress-strain curve in the plastic range where the curve is continuous and monotonic (see 7.4). In the case of materials with a serrated stre
33、ss-strain curve in the work hardening range (materials which show the Portevin-Le Chatelier effect, e.g. AlMg-alloys) the automatic determination (linear regression of the logarithm true stress vs. the logarithm true plastic strain, see 7.7) should be used to give reproducible results. 2 Normative r
34、eferences The following referenced documents are indispensable for the application of this document. For dated references, only edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 6892:1998, Metallic materials Tensile t
35、esting at ambient temperature ISO 7500-1:2004, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the force-measuring system ISO 9513:1999, Metallic materials Calibration of extensometers used in uniaxial t
36、esting ISO 10113, Metallic materials Sheet and strip Determination of plastic strain ratio 3 Symbols and designations The symbols and corresponding designations used in determining the tensile strain hardening exponent are given in Table 1. Metallic materials Sheet and strip Determination of tensile
37、 strain hardening exponent DIN EN ISO 10275:2014-085EN ISO 10275:2014 (E)Table 1 Symbols and designations Symbol Designation Units LeExtensometer gauge length (Le) mm L Instantaneous extension of the measurement base mm L Instantaneous length of the extensometer gauge length L = Le+ L mm epSpecified
38、 plastic (engineering) strain at which the tensile strain hardening exponent should be determined (single data point method) % ep epSpecified plastic (engineering) strain range at which the tensile strain hardening exponent should be determined (linear regression method, ep= lower limit of the plast
39、ic strain in percent, ep= upper limit of the plastic strain in percent) % SoOriginal cross-sectional area of the parallel length mm2S True cross-sectional area mm2F Instantaneous force applied to the test piece N R Stress MPa True stress MPa True plastic strain mESlope of the elastic part of the str
40、ess/percentage extension-curve MPa n Tensile strain hardening exponent C Strength coefficient MPa N Number of measurements made in determining the tensile strain hardening exponent r Plastic strain ratio RmTensile strength MPa AePercentage yield point extension % AgPercentage plastic extension at ma
41、ximum force % A, B, x, y Variables used for the evaluation of n by the manual method NOTE 1 In the literature the readers may encounter other symbols. For an international comparison of symbols, see Annex A. NOTE 2 1 MPa = 1 N/mm2. 3.2 The tensile strain hardening exponent n is defined as the expone
42、nt of the true plastic strain in the mathematical equation relating the true stress to the true plastic strain (during uniaxial application of a force). This equation can be taken as follows: nC = (1) 3.3 This equation can be transformed into a logarithmic one as follows: ln ln lnCn =+ (2) The strai
43、n hardening exponent in the logarithmic system of coordinates is defined as the slope of the corresponding straight line. DIN EN ISO 10275:2014-086EN ISO 10275:2014 (E) 4 Principle A test piece is subjected to uniaxial tensile strain at a prescribed constant rate within the region of uniform plastic
44、 strain. The tensile strain hardening exponent n is calculated either by considering a portion of the stress-strain curve in the plastic region, or by considering the whole uniform plastic strain region. 5 Test equipment 5.1 Tensile testing machine, verified and calibrated in accordance with ISO 750
45、0-1:2004 and of class 1 or better. The method of gripping the test piece shall conform to the requirements of ISO 6892. 5.2 Extensometer, of class 2 or better (class 1 in the event of determination of the plastic strain ratio r, see ISO 10113) in accordance with ISO 9513:1999, for measuring changes
46、in the gauge length. 5.3 Dimension-measuring equipment, capable of measuring the width and thickness of the parallel-sided section of the test piece to within the tolerances specified for these dimensions in ISO 6892. 6 Test pieces 6.1 Sampling to obtain test pieces shall be in accordance with the r
47、equirements of the relevant product standard or, if not specified therein, by agreement. Machining tolerances, tolerances on shape, and the marking shall be as specified in ISO 6892. 6.2 In the event of the plastic strain ratio r and the tensile strain hardening exponent n being determined simultane
48、ously, the conditions of ISO 10113 shall apply. 6.3 The thickness of the test piece shall be that of the full sheet, unless otherwise specified. 6.4 The surface of the test piece shall not be damaged (by scratches, etc.). 7 Procedure 7.1 In general, the test shall be carried out at ambient temperature, i.e. between 10 C and 35 C. Tests carried out under controlled conditions, where required, shall be made at a temperature of (23 5)C. 7.2 The test piece shall
