EN ISO 1798:2008

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Penjeni polimerni materiali - Ugotavljanje natezne trdnosti in raztezka pri pretrgu (ISO 1798:2008)Weich-elastische polymere Schaumstoffe - Bestimmung der Zugfestigkeit und der Bruchdehnung (ISO 1798:2008)Matériaux polymeres alvéolaires souples - Détermination de la résistance a la traction et de l'allongement a la rupture (ISO 1798:2008)Flexible cellular polymeric materials - Determination of tensile strength and elongation at break (ISO 1798:2008)83.100Penjeni polimeriCellular materialsICS:Ta slovenski standard je istoveten z:EN ISO 1798:2008SIST EN ISO 1798:2009en,fr,de01-februar-2009SIST EN ISO 1798:2009SLOVENSKI
STANDARDSIST EN ISO 1798:20001DGRPHãþD

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN ISO 1798February 2008ICS 83.100Supersedes EN ISO 1798:1999
English VersionFlexible cellular polymeric materials - Determination of tensilestrength and elongation at break (ISO 1798:2008)Matériaux polymères alvéolaires souples - Déterminationde la résistance à la traction et de l'allongement à larupture (ISO 1798:2008)Weich-elastische polymere Schaumstoffe - Bestimmungder Zugfestigkeit und der Bruchdehnung (ISO 1798:2008)This European Standard was approved by CEN on 12 January 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 ISO 1798:2008: ESIST EN ISO 1798:2009

Reference numberISO 1798:2008(E)© ISO 2008
INTERNATIONAL STANDARD ISO1798Fourth edition2008-02-01Flexible cellular polymeric materials — Determination of tensile strength and elongation at break Matériaux polymères alvéolaires souples — Détermination de la résistance à la traction et de l'allongement à la rupture
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ii © ISO 2008 – All rights reserved
ISO 1798:2008(E) © ISO 2008 – All rights reserved iiiContents Page Foreword.iv 1 Scope.1 2 Normative references.1 3 Terms and definitions.1 4 Apparatus.2 5 Test pieces.2 6 Procedure.4 7 Calculation.4 8 Test report.5 Annex A (informative)
Comparative testing of type 1 and type 1A test pieces.6 Bibliography.11
ISO 1798:2008(E) iv © ISO 2008 – All rights reserved Foreword 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 which 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 matters 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 circulated 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 responsible for identifying any or all such patent rights. ISO 1798 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 4, Products (other than hoses). This fourth edition cancels and replaces the third edition (ISO 1798:1997), which has been technically revised. It also incorporates the Technical Corrigendum ISO 1798:1997/Cor.1:2003. The main change is the introduction of a second type of test piece (see Figure 1) and a comparison of the results obtained with the two test pieces (see Annex A).
INTERNATIONAL STANDARD ISO 1798:2008(E) © ISO 2008 – All rights reserved 1Flexible cellular polymeric materials — Determination of tensile strength and elongation at break WARNING — Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. 1 Scope This International Standard specifies a method for determining the strength and deformation properties of flexible cellular materials when a test piece is extended at a constant rate until it breaks. 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. ISO 1923, Cellular plastics and rubbers — Determination of linear dimensions 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, Metallic materials — Calibration of extensometers used in uniaxial testing ISO 23529, Rubber — General procedures for preparing and conditioning test pieces for physical test methods 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 tensile strength TS maximum tensile stress applied when stretching a test piece to rupture 3.2 elongation at break Eb percentage elongation of a test piece at rupture SIST EN ISO 1798:2009

ISO 1798:2008(E) 2 © ISO 2008 – All rights reserved 4 Apparatus 4.1 Tensile-testing machine, complying with the following requirements: ⎯ the rate of travel of the power-actuated grip shall be 500 mm/min ± 50 mm/min and shall be uniform at all times; ⎯ the accuracy of the machine shall conform to class 0,5 or class 1 of ISO 7500-1:2004 for force-measurement over the range of loading employed. For the determination of elongation at break, the machine may be equipped with either a mechanical or an optical extensometer. If used, however, the extensometer shall comply with the following requirements which shall be verified in accordance with ISO 9513: ⎯ initial gauge length accurate to ± 1 %; ⎯ gauge length at break accurate to ± 1,25 mm. When a mechanical contact extensometer is used, care shall be taken that the contact elements do not damage the test piece. In addition, their mass and inertia shall not influence the determination of the maximum tensile strength by more than 1 %. 5 Test pieces 5.1 Direction of sampling If the product shows a predominant direction of the cellular structure (orientation of the cells), the test pieces for the tensile test shall be taken in such a way that their longitudinal axes lie at right angles to this predominant direction. If it is not possible, the location of the longitudinal axis with respect to the predominant direction shall be stated in the test report. 5.2 Shape and dimensions The test pieces shall be rectangular in cross-section, with or without skin, and without visible defects. The test pieces shall be cut out with one of the two types of test piece cutter shown in Figure 1 and shall be 10 mm to 15 mm thick. 5.3 Number of test pieces Unless agreed otherwise between the interested parties, sufficient test pieces shall be tested to provide five breaks within the gauge length. SIST EN ISO 1798:2009

ISO 1798:2008(E) © ISO 2008 – All rights reserved 3Dimensions in millimetres
a)
Type 1
b)
Type 1A Figure 1 — Test-piece cutters 5.4 Conditioning 5.4.1 The test pieces or the material from which the test pieces are to be cut shall be prepared and conditioned in accordance with ISO 23529, unless otherwise specified. 5.4.2 Materials shall not be tested less than 72 h after manufacture, unless at either 16 h or 48 h after manufacture it can be demonstrated that the mean results do not differ by more than ± 10 % from those obtained after 72 h. Testing is permitted at either 16 h or 48 h if, at the specified time, the above criterion has been satisfied. Prior to the test, the test pieces or the material from which the test pieces are to be cut shall be conditioned for at least 16 h in one of the following atmospheres: ⎯ 23 °C ± 2 °C, (50 ± 5) % relative humidity; ⎯ 27 °C ± 2 °C, (65 ± 5) % relative humidity. This period can form the latter part of the period following manufacture. 5.4.3 In the case of quality-control tests, test pieces can be taken a shorter time (down to a minimum of 12 h) after manufacture and testing carried out after conditioning for a shorter period (down to a minimum of 6 h) in one of the atmospheres specified above. SIST EN ISO 1798:2009

ISO 1798:2008(E) 4 © ISO 2008 – All rights reserved 6 Procedure 6.1 After conditioning as specified in 5.4, measure the thickness of the material at five evenly distributed points in the area from which the test pieces are to be cut. These measurements shall be made in accordance with ISO 1923 and shall not vary from each other by more than ± 2 %. If desired, thickness measurements can be perfo
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