1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 26203-1:2010Metallic materials Tensiletesting at high strain ratesPart 1: Elastic-bar-type systems (ISO26203-1:2010)BS EN ISO 26203-1:2010 BRITISH STANDARDNational fore
2、wordThis British Standard is the UK implementation of EN ISO26203-1:2010.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/101/1, Uniaxial testing.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not
3、purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 56156 6ICS 77.040.10Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theSta
4、ndards Policy and Strategy Committee on 31 August 2010.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 26203-1 February 2010 ICS 77.040.10 English Version Metallic materials - Tensile testing at high strain rates - Part 1: Elastic-bar-typ
5、e systems (ISO 26203-1:2010) Matriaux mtalliques - Essai de traction vitesses de dformation leves - Partie 1: Systmes de type barre lastique (ISO 26203-1:2010) Metallische Werkstoffe - Zugversuch bei hohen Dehngeschwindigkeiten - Teil 1: Elastische Stowellentechnik (ISO 26203-1:2010) This European S
6、tandard was approved by CEN on 6 February 2010. 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 standard without any alteration. Up-to-date lists and bibliographical references concern
7、ing such national standards 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 translation under the responsibility of a CEN member into its own
8、language and notified to the CEN Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
9、 Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels
10、2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 26203-1:2010: EBS EN ISO 26203-1:2010EN ISO 26203-1:2010 (E) 3 Foreword This document (EN ISO 26203-1:2010) has been prepared by Technical Committee ISO/TC 164 “Mechanical te
11、sting of metals“ in collaboration with Technical Committee ECISS/TC 101 “Test methods for steel (other than chemical analysis)” 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 endorse
12、ment, at the latest by August 2010, and conflicting national standards shall be withdrawn at the latest by August 2010. 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
13、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, France, Germany,
14、 Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 26203-1:2010 has been approved by CEN as a EN ISO 26203-1:2010 wi
15、thout any modification. BS EN ISO 26203-1:2010ISO 26203-1:2010(E) ISO 2010 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references1 3 Principles1 4 Terms and definitions .2 5 Symbols and designations.2 6 Apparatus.4 7 Test piece .5 7.1 Test-piece shape, size a
16、nd preparation 5 7.2 Typical test piece.7 8 Calibration of the apparatus.8 8.1 General .8 8.2 Displacement measuring device9 9 Procedure.9 9.1 General .9 9.2 Mounting the test piece 9 9.3 Applying force .9 9.4 Measuring and recording9 10 Evaluation of the test result .11 11 Test report12 Annex A (in
17、formative) Quasi-static tensile testing method14 Annex B (informative) Example of one-bar method 16 Annex C (informative) Example of split Hopkinson bar (SHB) method.23 Bibliography31 BS EN ISO 26203-1:2010ISO 26203-1:2010(E) iv ISO 2010 All rights reservedForeword ISO (the International Organizatio
18、n for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has
19、 the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Inter
20、national Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publicat
21、ion as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent righ
22、ts. ISO 26203-1 was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee SC 1, Uniaxial testing. ISO 26203 consists of the following parts, under the general title Metallic materials Tensile testing at high strain rates: Part 1: Elastic-bar-type systems Part 2: Serv
23、o-hydraulic and other test systems BS EN ISO 26203-1:2010ISO 26203-1:2010(E) ISO 2010 All rights reserved vIntroduction Tensile testing of metallic sheet materials at high strain rates is important to achieve a reliable analysis of vehicle crashworthiness. During a crash event, the maximum strain ra
24、te often reaches 103s1, at which the strength of the material can be significantly higher than that under quasi-static loading conditions. Thus, the reliability of crash simulation depends on the accuracy of the input data specifying the strain-rate sensitivity of the materials. Although there are s
25、everal methods for high-strain rate testing, solutions for three significant problems are required. The first problem is the noise in the force measurement signal. The test force is generally detected at a measurement point on the force measurement device that is located some distance away from the
26、test piece. Furthermore, the elastic wave which has already passed the measurement point returns there by reflection at the end of the force measurement device. If the testing time is comparable to the time for wave propagation through the force measurement device, the stress-strain curve may have l
27、arge oscillations as a result of the superposition of the direct and indirect waves. In quasi-static testing, contrarily, the testing time is sufficiently long to have multiple round-trips of the elastic wave. Thus, the force reaches a saturated state and equilibrates at any point of the force measu
28、rement device. There are two opposing solutions for this problem. The first solution is to use a short force measurement device which will reach the saturated state quickly. This approach is often adopted in the servo-hydraulic type system. The second solution is to use a very long force measurement
29、 device which allows the completion of a test before the reflected wave returns to the measurement point. The elastic-bar type system is based on the latter approach. The second problem is the need for rapid and accurate measurements of displacement or test piece elongation. Conventional extensomete
30、rs are unsuitable because of their large inertia. Non-contact type methods such as optical and laser devices should be adopted. It is also acceptable to measure displacements using the theory of elastic wave propagation in a suitably-designed apparatus, examples of which are discussed in this docume
31、nt. The displacement of the bar end can be simply calculated from the same data as force measurement, i.e. the strain history at a known position on the bar. Thus, no assessment of machine stiffness is required in the elastic-bar-type system. The last problem is the inhomogeneous section force distr
32、ibuted along the test piece. In quasi-static testing, a test piece with a long parallel section and large fillets is recommended to achieve a homogeneous uniaxial-stress state in the gauge section. In order to achieve a valid test with force equilibrium during the dynamic test, the test piece must b
33、e designed differently from the typically designed quasi-static test piece. Dynamic test pieces must generally be smaller in the dimension parallel to the loading axis than the test pieces typically used for quasi-static testing. BS EN ISO 26203-1:2010ISO 26203-1:2010(E) vi ISO 2010 All rights reser
34、vedThe elastic-bar-type system can thus provide solutions for dynamic testing problems and is widely used to obtain accurate stress-strain curves at around 103s1. The International Iron and Steel Institute developed the “Recommendations for Dynamic Tensile Testing of Sheet Steel” based on the interl
35、aboratory test conducted by various laboratories. The interlaboratory test results show the high data quality obtained by the elastic-bar type system. The developed knowledge on the elastic-bar-type system is summarized in this part of ISO 26203; part 2 of ISO 26203 covers servo-hydraulic and other
36、test systems used for high-strain-rate tensile testing. BS EN ISO 26203-1:2010INTERNATIONAL STANDARD ISO 26203-1:2010(E) ISO 2010 All rights reserved 1Metallic materials Tensile testing at high strain rates Part 1: Elastic-bar-type systems 1 Scope This International Standard specifies methods for te
37、sting metallic sheet materials to determine the stress-strain characteristics at high strain rates. This part of ISO 26203 covers the use of elastic-bar-type systems. The strain-rate range between 103to 103s1is considered to be the most relevant to vehicle crash events based on experimental and nume
38、rical calculations such as the Finite Element Analysis (FEA) work for crashworthiness. In order to evaluate the crashworthiness of a vehicle with accuracy, reliable stress-strain characterization of metallic materials at strain rates higher than 103s1is essential. This test method covers the strain-
39、rate range above 102s1. NOTE 1 At strain rates lower than 101s1, a quasi-static tensile testing machine that is specified in ISO 7500-1 and ISO 6892-1 can be applied. NOTE 2 This testing method may be applied to tensile test-piece geometries other than the flat test pieces considered here. 2 Normati
40、ve 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 6892-1, Metallic materials Tens
41、ile testing Part 1: Method of test at room temperature 3 Principles The stress-strain characteristics of metallic materials at high strain rates are evaluated. At a strain rate higher than 10 s1, the signal of the loading force is greatly perturbed by multiple passages of waves reflected within the
42、load cell that is used in the quasi-static test. Thus, special techniques are required for force measurement. This may be accomplished in two opposite ways: one is to lengthen the force measurement device in the loading direction, in order to finish the measurement before the elastic wave is reflect
43、ed back from the other end (elastic-bar type systems); another way is to shorten the force measurement device, thus reducing the time needed to attain dynamic equilibrium within the force measurement device and realizing its higher natural frequency (servo-hydraulic type systems). BS EN ISO 26203-1:
44、2010ISO 26203-1:2010(E) 2 ISO 2010 All rights reservedTests at low strain rates (under 101s1) can be carried out using a quasi-static tensile testing machine. However, special considerations are required when this machine is used for tests at strain rates higher than conventional ones. It is necessa
45、ry to use a test piece specified for high-strain-rate testing methods. Annex A provides details of the test procedure for this practice. 4 Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1 elastic-bar-type system measuring system in which the for
46、ce-measuring device is lengthened in the axial direction to prevent force measurement from being affected by waves reflected from the ends of the apparatus NOTE The designation “elastic-bar-type system” comes from the fact that this type of system normally employs a long elastic bar as force-measuri
47、ng device. 5 Symbols and designations Symbols and corresponding designations are given in Table 1. Table 1 Symbols and designations Symbol Unit Designation Test piece aomm Original thickness of a flat test piece bomm Original width of the parallel length of a flat test piece bgmm Width(s) of the gri
48、p section of a test piece Lomm Original gauge length see 7.1 e) Lcmm Parallel length Ltotalmm Total length that includes the parallel length and the shoulders Lumm Final gauge length after fracture r mm Radius of the shoulder Somm2Original cross-sectional area of the parallel length Sbmm2Cross-secti
49、onal area of the elastic bar Time t s Time Elongation A % Percentage elongation after fracture NOTE With non-proportional test pieces, the symbol A is supplemented with an index which shows the basic initial measured length in millimetres, e.g. A20mm= Percentage elongation after fracture with an original gauge length Lo= 20 mm Au% Specified upper limit of percentage elongation for mean strain rate BS EN ISO 26203-1:2010ISO 26203-1:2010(E) ISO 2010 All rights reserved 3Table 1 (continued) Symb
