1、March 2012 Translation by DIN-Sprachendienst.English price group 7No 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 5
2、9.140.30!$zd“1875865www.din.deDDIN EN ISO 3376Leather Physical and mechanical tests Determination of tensile strength and percentage extension(ISO 3376:2011)English translation of DIN EN ISO 3376:2012-03Leder Physikalische und mechanische Prfungen Bestimmung der Zugfestigkeit und der prozentualen De
3、hnung (ISO 3376:2011)Englische bersetzung von DIN EN ISO 3376:2012-03Cuir Essais physiques et mcaniques Dtermination de la rsistance la traction et du pourcentage dallongement(ISO 3376:2011)Traduction anglaise de DIN EN ISO 3376:2012-03SupersedesDIN EN ISO 3376:2003-10www.beuth.deDocument comprises
4、pagesIn case of doubt, the German-language original shall be considered authoritative.1003.12 DIN EN ISO 3376:2012-03 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee CEN/TC 289 “Leather” (Secretariat: UNI, Italy) in collaboration with
5、 the International Union of Leather Technologists and Chemists Societies (IULTCS). This standard is in accordance with the IUP 6:2011 method. The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Working Committee NA 0
6、62-05-51 AA Anforderungen und physika-lische Prfverfahren fr Leder und seine Ausgangsprodukte. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 2418 DIN EN ISO 2418 ISO 2419 DIN EN ISO 2419 ISO 2589 DIN EN ISO 2589 ISO 7500-1 DIN EN ISO
7、7500-1 Amendments This standard differs from DIN EN ISO 3376:2003-10 as follows: a) a tensile testing machine with a means of recording the force has been included; b) the test report has been extended to include more information. Previous editions DIN 53328: 1944-02, 1970-12, 1979-02 DIN EN ISO 337
8、6: 2003-10 National Annex NA (informative) Bibliography DIN EN ISO 2418, Leather Chemical, physical and mechanical and fastness tests Sampling location DIN EN ISO 2419, Leather Physical and mechanical tests Sample preparation and conditioning cal tests Determination of thickness DIN EN ISO 7500-1, M
9、etallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the force-measuring system Leather Physical and mechaniDIN EN ISO 2589, EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 3376 December 2011 ICS 59.1
10、40.30 Supersedes EN ISO 3376:2002English Version Leather - Physical and mechanical tests - Determination of tensile strength and percentage extension (ISO 3376:2011) Cuir - Essais physiques et mcaniques - Dtermination de la rsistance la traction et du pourcentage dallongement (ISO 3376:2011) Leder -
11、 Physikalische und mechanische Prfungen - Bestimmung der Zugfestigkeit und der prozentualen Dehnung (ISO 3376:2011) This European Standard was approved by CEN on 14 December 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
12、 European Standard the status of a national standard 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 ve
13、rsions (English, French, German). A version in 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 Austri
14、a, Belgium, Bulgaria, Croatia, 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. EUROPE
15、AN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 3376:2011: EDIN EN ISO 337
16、6:2012-03 EN ISO 3376:2011 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Normative references 4 3 Principle 4 4 Apparatus .4 5 Sampling and sample preparation .5 6 Procedure .6 6.1 Determination of dimensions .6 6.2 Determination of tensile strength 6 6.3 Determination of the percentage elongation caus
17、ed by a specified load .6 6.4 Determination of the percentage elongation at break .6 6.5 Slippage 6 7 Expression of results 7 7.1 Tensile strength .7 7.2 Percentage elongation caused by a specified load .7 7.3 Percentage elongation at break .7 8 Test report 8 Foreword This document (EN ISO 3376:2011
18、) has been prepared by Technical Committee CEN/TC 289 “Leather”, the secretariat of which is held by UNI, in collaboration with the International Union of Leather Technologists and Chemists Societies. This European Standard shall be given the status of a national standard, either by publication of a
19、n identical text or by endorsement, at the latest by June 2012, and conflicting national standards shall be withdrawn at the latest by June 2012. 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
20、 responsible for identifying any or all such patent rights. This document supersedes EN ISO 3376:2002. 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
21、, 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. DIN EN ISO 3376:2012-03 EN ISO
22、3376:2011 (E) 3 1 Scope This International Standard specifies a method for determining the tensile strength, elongation at a specified load and elongation at break of leather. It is applicable to all types of leather. 2 Normative references The following referenced documents are indispensable for th
23、e 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 2418, Leather Chemical, physical and mechanical and fastness tests Sampling location ISO 2419, Leather P
24、hysical and mechanical tests Sample preparation and conditioning ISO 2589, Leather Physical and mechanical tests Determination of thickness ISO 7500-1:2004, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration o
25、f the force-measuring system 3 Principle A test piece is extended at a specified rate until the forces reach a predetermined value or until the test piece breaks. 4 Apparatus 4.1 Tensile testing machine, with: a force range appropriate to the specimen under test; a means of recording the force to an
26、 accuracy of at least 2 % as specified by Class 2 of ISO 7500-1; a uniform speed of separation of the jaws of 100 mm/min 20 mm/min; a means of recording the force, e.g. as an extension curve; jaws, minimum length 45 mm in the direction of the applied load, designed to apply constant clamping by mech
27、anical or pneumatic means. The texture and design of the inside faces of the jaws shall be such that, at the maximum load attained in the test, the specimen does not slip in either jaw by an amount exceeding 1 % of the original jaw separation. DIN EN ISO 3376:2012-03 EN ISO 3376:2011 (E) 4 4.2 A mea
28、ns of determining the extension of the test piece, either by monitoring the separation of the jaws or by sensors which monitor the separation of two fixed points on the test piece. 4.3 Thickness gauge, as specified in ISO 2589. 4.4 Press knives, as specified in ISO 2419, capable of cutting a test pi
29、ece as shown in Figure 1 to the dimensions given in Table 1. Figure 1 Shape of test piece Table 1 Dimensions of test pieces Dimensions in millimetres Designation l l1l2b b1R Standard 110 50 30 10 20 5 Large 190 100 45 20 40 10 4.5 Vernier callipers, reading to 0,1 mm. 5 Sampling and sample preparati
30、on 5.1 Sample in accordance with ISO 2418. 5.2 From the sample, cut six test pieces in accordance with ISO 2419 by applying a press knife (4.4) to the grain surface, three test pieces with the longer sides parallel to the backbone and three test pieces with the longer sides perpendicular to the back
31、bone. If previous testing has shown that there is slippage of the test piece in the jaws, use the large press knife (4.4). If there is a requirement for more than two hides or skins to be tested in one batch, then only one test piece in each direction need be taken from each hide or skin, provided t
32、hat the overall total is not less than three test pieces in each direction. 5.3 Condition the test pieces in accordance with ISO 2419. DIN EN ISO 3376:2012-03 EN ISO 3376:2011 (E) 5 6 Procedure 6.1 Determination of dimensions 6.1.1 Using vernier callipers (4.5), measure the width of each test piece
33、to the nearest 0,1 mm at three positions on the grain side and three on the flesh side. In each group of three measurements, make one at the mid-point E (as shown in Figure 1) and the other two at positions approximately midway between the mid-point E and the lines AB and CD. Take the arithmetic mea
34、n of the six measurements as the width of the test piece, w. For soft (“flexible”) leather, the width shall be taken as the width of the press knife. 6.1.2 Measure the thickness of each test piece in accordance with ISO 2589. Make the measurements at three positions, namely the mid-point E and at po
35、sitions approximately midway between the mid-point E and the lines AB and CD. Take the arithmetic mean of the three measurements as the thickness of the test piece, t. 6.2 Determination of tensile strength 6.2.1 Set the jaws of the tensile testing apparatus (4.1) 50 mm 1 mm apart if using the standa
36、rd test piece or 100 mm apart if using the large test piece. Clamp the test piece in the jaws so that the edges of the jaws lie along the lines AB and CD. When the test piece is clamped, ensure its grain surface lies in one plane. The length axis shall be parallel to the traction direction. 6.2.2 Ru
37、n the machine until the test piece breaks and record the highest force exerted as the breaking force, F. 6.3 Determination of the percentage elongation caused by a specified load 6.3.1 Clamp the test piece between the jaws of the apparatus, as described in 6.2.1. Measure the distance between the jaw
38、s at least to the nearest 0,5 mm and record this distance, L0, as the initial length of the test piece for the purpose of the test. 6.3.2 Start the test. Unless the apparatus automatically draws a force/extension curve with the necessary accuracy (see 4.2), follow the distance between the pair of ja
39、ws or the sensors as the force increases. 6.3.3 Note the distance, in millimetres, between the pair of jaws or sensors at the instant when the force first reaches the specified value. This distance represents the length of the test piece at this force, L1. Do not stop the apparatus if results from t
40、he procedures described in 6.2 or 6.4 are also required. 6.4 Determination of the percentage elongation at break 6.4.1 Carry out the steps given in 6.3.1. 6.4.2 Run the tensile test machine until the test piece breaks. 6.4.3 Record the distance between the jaws or sensors at the instant when rupture
41、 of the test piece occurs. This distance represents the length of the test piece at break, L2. 6.5 Slippage If there is slippage of the test piece in either jaw when tested according to 6.2, 6.3 or 6.4, and the slippage is greater than 1 % of the initial jaw separation, reject the result and repeat
42、the determination with a new test piece cut using the large press knife (4.4). DIN EN ISO 3376:2012-03 EN ISO 3376:2011 (E) 6 7 Expression of results 7.1 Tensile strength The tensile strength, Tn, in MPa (or newtons per square millimetre, if required) shall be calculated using the equation: nFTwtwhe
43、re F is the highest force recorded, in newtons; w is the mean width of the test piece, in millimetres; t is the mean thickness of the test piece, in millimetres. NOTE The relationship between MPa and N/mm2is the following: 1 N/mm2 1 MPa. 7.2 Percentage elongation caused by a specified load The perce
44、ntage elongation caused by a specified load, E1, shall be calculated using the equation: 1010100LLEL where L1is the separation of the jaws or sensors at the specified load; L0is the initial separation of the jaws or sensors. 7.3 Percentage elongation at break The percentage elongation at break, Eb,
45、shall be calculated using the equation: 20b0100LLEL where L2is the separation of the jaws or sensors at break; L0is the initial separation of the jaws or sensors. DIN EN ISO 3376:2012-03 EN ISO 3376:2011 (E) 7 8 Test report The test report shall include the following: a) a reference to this Internat
46、ional Standard, i.e. ISO 3376:2011; b) the mean tensile strength, in MPa (or newtons per square millimetre), to the nearest 0,1 MPa, for the test pieces with the longer edge cut parallel to the backbone; c) the mean tensile strength, in MPa (or newtons per square millimetre), to the nearest 0,1 MPa,
47、 for the test pieces with the longer edge cut perpendicular to the backbone; d) the mean percentage elongation at break to the nearest 1 %, for the test pieces with the longer edge cut parallel to the backbone; e) the mean percentage elongation at break to the nearest 1 %, for the test pieces with t
48、he longer edge cut perpendicular to the backbone; f) the mean percentage elongation at a specified load to the nearest 1 %, for the test pieces with the longer edge cut parallel to the backbone; if required; g) the mean percentage elongation at a specified load to the nearest 1 %, for the test pieces with the longer edge cut perpendicular to the backbone, if required; h) the thickness of the sample, in millimetres, in accordance with ISO 2589; i) any deviations from the metho
