1、BS EN ISO1924-2:2008ICS 85.060NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDPaper and board Determination oftensile propertiesPart 2: Constant rate of elongationmethod (20 mm/min) (ISO 1924-2:2008)This British Standardwas published under theauthority of the St
2、andardsPolicy and StrategyCommittee on 28 February2009 BSI 2009ISBN 978 0 580 58756 6Amendments/corrigenda issued since publicationDate CommentsBS EN ISO 1924-2:2008National forewordThis British Standard is the UK implementation of EN ISO 1924-2:2008.It supersedes BS EN ISO 1924 :1995 which is withd
3、rawn.The UK participation in its preparation was entrusted to TechnicalCommittee PAI/11, Methods of test for paper, board and pulps.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisio
4、nsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunityfrom legal obligations.-2EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 1924-2December 2008ICS 85.060 Supersedes EN ISO 1924-2:1995 English VersionPaper and board - Dete
5、rmination of tensile properties - Part 2:Constant rate of elongation method (20 mm/min) (ISO 1924-2:2008)Papier et carton - Dtermination des proprits de traction -Partie 2: Mthode gradient dallongement constant (20mm/min) (ISO 1924-2:2008)Papier und Pappe - Bestimmung von Eigenschaften beiZugbeanspr
6、uchung - Teil 2: Verfahren mit konstanterDehngeschwindigkeit (20 mm/min) (ISO 1924-2:2008)This European Standard was approved by CEN on 19 November 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the statu
7、s 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 ve
8、rsion 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, Den
9、mark, 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 STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIO
10、NEUROPISCHES KOMITEE FR NORMUNGManagement Centre: Avenue Marnix 17, B-1000 Brussels 2008 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 1924-2:2008: EBS EN ISO 1924-2:2008EN ISO 1924-2:2008 (E) 3 Foreword This document (EN ISO 1
11、924-2:2008) has been prepared by Technical Committee ISO/TC 6 “Paper, board and pulps“ in collaboration with Technical Committee CEN/TC 172 “Pulp, paper and board“, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication
12、 of an identical text or by endorsement, at the latest by June 2009, and conflicting national standards shall be withdrawn at the latest by June 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
13、 held responsible for identifying any or all such patent rights. This document supersedes EN ISO 1924-2:1995. 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,
14、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. Endorsement notice The text of IS
15、O 1924-2:2008 has been approved by CEN as a EN ISO 1924-2:2008 without any modification. BS EN ISO 1924-2:2008ISO 1924-2:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2 Normative references1 3 Terms and definitions .2 4 Principle2 5 Apparatus.3 6 Calibrati
16、on and adjustment of apparatus .4 7 Sampling and preparation of test pieces4 7.1 Sampling.4 7.2 Conditioning 4 7.3 Preparation of test pieces.5 8 Procedure.5 9 Calculation and report 6 9.1 General .6 9.2 Tensile strength.6 9.3 Tensile index6 9.4 Strain at break6 9.5 Tensile energy absorption7 9.6 Te
17、nsile energy absorption index .7 9.7 Modulus of elasticity.7 10 Precision.8 10.1 General .8 10.2 Repeatability 8 10.3 Reproducibility 8 11 Test report10 Annex A (normative) Calibration of the tensile testing machine.11 Bibliography12 BS EN ISO 1924-2:2008ISO 1924-2:2008(E) iv ISO 2008 All rights res
18、ervedForeword ISO (the International Organization 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 whic
19、h a technical committee has been established has 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 ma
20、tters of electrotechnical standardization. International 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 circ
21、ulated to the member bodies for voting. Publication 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 respons
22、ible for identifying any or all such patent rights. ISO 1924-2 was prepared by Technical Committee ISO/TC 6, Paper, board and pulps, Subcommittee SC 2, Test methods and quality specifications for paper and board. This third edition cancels and replaces the second edition (ISO 1924-2:1994), which has
23、 been technically revised with respect to terms and definitions (in order to be in line with the terms and definitions used in ISO 1924-31). The numbering of clauses and their contents have been changed to be congruent with ISO 1924-3. ISO 1924 consists of the following parts, under the general titl
24、e Paper and board Determination of tensile properties1): Part 2: Constant rate of elongation method (20 mm/min) Part 3: Constant rate of elongation method (100 mm/min) 1) ISO 1924-1, Constant rate of loading method, was withdrawn in 2004 as it was considered obsolete. BS EN ISO 1924-2:2008ISO 1924-2
25、:2008(E) ISO 2008 All rights reserved vIntroduction The method for determination of tensile properties specified in this part of ISO 1924 is the one most commonly used. It is related to the method specified in ISO 1924-3. In this part of ISO 1924 (ISO 1924-2), the constant rate of elongation applied
26、 is 20 mm/min, whereas in ISO 1924-3, the constant rate of elongation applied is 100 mm/min. Since the results of a tensile test depend on the rate of elongation applied, this part of ISO 1924 and ISO 1924-3 will not give the same results. The rate dependence can vary according to paper grade and is
27、 different for tensile strength, strain at break, tensile energy absorption and modulus of elasticity. NOTE 1 In most cases, the tensile properties can increase by 5 % to 15 % when the rate of elongation is increased from 20 mm/min (180 mm test span length) to 100 mm/min (100 mm test span length). N
28、OTE 2 In this part of ISO 1924, the same terminology and symbols are used as in ISO 1924-3 and in general literature concerning materials physics and mechanics. BS EN ISO 1924-2:2008BS EN ISO 1924-2:2008INTERNATIONAL STANDARD ISO 1924-2:2008(E) ISO 2008 All rights reserved 1Paper and board Determina
29、tion of tensile properties Part 2: Constant rate of elongation method (20 mm/min) 1 Scope This part of ISO 1924 specifies a method for measuring the tensile strength, strain at break and tensile energy absorption of paper and board, using a testing machine operating at a constant rate of elongation
30、(20 mm/min). This part of ISO 1924 also specifies equations for calculating the tensile index, the tensile energy absorption index and the modulus of elasticity. Testing in conformance with this part of ISO 1924 always includes the measurement of tensile strength. Measurement or calculation of other
31、 properties is subject to agreement between the parties concerned. This part of ISO 1924 is applicable to all papers and boards, including papers with a high strain at break if the results are within the capacity of the testing machine. It also applies to the components of corrugated board but not,
32、however, to corrugated board itself. This part of ISO 1924 is not applicable to tissue paper and tissue products for which ISO 12625-42is applicable. For the determination of tensile properties of laboratory sheets, ISO 52703is recommended. 2 Normative references The following referenced documents a
33、re 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 186, Paper and board Sampling to determine average quality ISO 187, Paper, board
34、and pulps Standard atmosphere for conditioning and testing and procedure for monitoring the atmosphere and conditioning of samples ISO 534, Paper and board Determination of thickness, density and specific volume ISO 536, Paper and board Determination of grammage BS EN ISO 1924-2:2008ISO 1924-2:2008(
35、E) 2 ISO 2008 All rights reserved3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 tensile strength maximum tensile force per unit width that paper and board will withstand before breaking under the conditions defined in this International Stan
36、dard 3.2 tensile index tensile strength divided by the grammage 3.3 elongation increase in length of a test piece NOTE Elongation is expressed in millimetres. 3.4 strain ratio of the elongation of a test piece to the initial test length NOTE 1 Strain is expressed as a percentage of the initial test
37、length. NOTE 2 The initial test length of the test piece is the same as the initial span between the clamping lines. 3.5 strain at break ratio of the measured elongation at the moment of rupture of a test piece of paper, when extended under the conditions defined in the standard method of test, to t
38、he initial test length 3.6 tensile energy absorption amount of energy per unit surface area of a test piece when it is strained to the maximum tensile force NOTE Surface area is calculated as test length multiplied by width. 3.7 tensile energy absorption index tensile energy absorption divided by th
39、e grammage 3.8 modulus of elasticity maximum slope of the force-elongation curve multiplied by the initial length divided by the width and the thickness of the test piece NOTE See also Figure 2. 4 Principle A test piece of given dimensions is strained to break at a constant rate of elongation using
40、a testing machine that records both the tensile force and, if required, the elongation. If the tensile force and elongation are continuously recorded, the strain at break, the tensile energy absorption and the modulus of elasticity may be determined. From the recorded data, and the knowledge of the
41、grammage of the sample, the tensile index and the tensile energy absorption index may be calculated. BS EN ISO 1924-2:2008ISO 1924-2:2008(E) ISO 2008 All rights reserved 35 Apparatus 5.1 Tensile testing machine, designed to extend a test piece of given dimensions at an appropriate constant rate of e
42、longation (20 mm/min), and to measure the tensile force and, if required, the elongation produced. The tensile testing machine includes means of measuring and indicating the tensile force to an accuracy of 1 % of the true force and, if required, the elongation to an accuracy of 0,1 % elongation. The
43、 tensile force may be recorded as a function of the elongation on an electronic integrator or an equivalent device. NOTE 1 The accuracy of measurement of elongation is very important. An appropriate extensometer, placed directly on the test piece, is recommended for accurate measurement of true elon
44、gation (see ISO 9513, class 1 or class 0,5). This is to avoid the possibility of including in the measurement any apparent elongation which can result from undetected slippage of the test piece in the clamps or from the take-up in the joints of the apparatus. The latter is dependent upon the load ap
45、plied and the error can increase due to wear of the joints of an apparatus which has been in use for some time. It is advisable that means be applied to limit additional loads, which an extensometer would apply to the test piece, to the required accuracy of the tensile force. The tensile testing mac
46、hine also includes two clamps, for holding a test piece of the required width (see 7.3). Each clamp shall be designed to grip the test piece firmly, but without damage or slippage, along a straight line across the full width of the test piece and have a means of adjusting the clamping force. The cla
47、mping surfaces of the clamps shall be in the same plane and so aligned that they hold the test piece in that plane throughout the test. NOTE 2 It is advisable that the clamps grip the test piece between a cylindrical and a flat surface, or between two cylindrical surfaces, with the plane of the test
48、 piece tangential to the cylindrical surface. Other types of clamps can be used provided no slippage of, or damage to, the test piece occurs during test. When the test piece is clamped, the clamping lines shall be parallel to each other within a maximum angle of 1 (see Figure 1). In addition, the cl
49、amping lines shall remain perpendicular to the direction of the applied tensile force, and to the long dimension of the test piece, to within a maximum of 1, while under load (see Figure 1). The distances between the clamping lines shall be adjustable to the test length required to within 1 mm. aClamping lines parallel to each other within a maximum angle of 1. bCentreline of test piece perpendicular to clamping lines to within a maximum angle of 1. cTensile force parallel to the test piece centreline to within a maxi
