1、BRITISH STANDARD BS EN ISO 5079:1996 Textiles Fibres Determination of breaking force and elongation at break of individual fibres The European Standard ENISO5079:1995 has the status of a British Standard ICS 59.060BS EN ISO 5079:1996 This British Standard, having been prepared under the directionof
2、the Sector Board for Materials and Chemicals, was published under the authorityof the Standards Boardand comes into effect on 15 May 1996 BSI 10-1999 The following BSI references relate to the work on this standard: Committee reference TCI/24 Draft for comment 93/306144 DC ISBN 0 580 25726 6 Committ
3、ees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee TCI/24, Physical testing of textiles, upon which the following bodies were represented: Association of Consulting Scientists Association of Suppliers to the British Clothing Indust
4、ry British Apparel and Textile Confederation British Measurement and Testing Association British Polyolefin Textiles Association British Textile Machinery Association British Textile Technology Group British Throwsters Association Furniture Industry Research Association International Wool Secretaria
5、t Ministry of Defence SATRA Footwear Technology Centre Society of Dyers and Colourists Textile Finishers Association Textile Institute Amendments issued since publication Amd. No. Date CommentsBS EN ISO 5079:1996 BSI 10-1999 i Contents Page Committees responsible Inside front cover National foreword
6、 ii Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Principle 4 5 Apparatus and reagents 4 6 Conditioning and testing atmospheres 4 7 Sampling 4 8 Procedure 5 9 Expression of results 5 10 Test report 6 Annex A (informative) Mounting of test specimens 7 Annex ZA (normative) Normative
7、references to international publications withtheir relevant European publications 7 Figure 1 Typical force/elongation curve 3 Table 1 Pretension forces 5 List of references Inside back coverBS EN ISO 5079:1996 ii BSI 10-1999 National foreword This British Standard has been prepared by Technical Comm
8、ittee TCI/24 and is the English language version of ENISO5079:1995, Textiles Fibres Determination of breaking force and elongation at break of individual fibres, published by the European Committee for Standardization (CEN). It is identical with ISO5079:1995, published by the International Organizat
9、ion for Standardization (ISO). This British Standard supersedes BS3411:1971 which is withdrawn. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does
10、 not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Standard EN 21039:1992 (ISO 139:1973) BS EN 20139:1992 Textiles Standard atmospheres for conditioning and testing ISO 1130:1975 BS 2545:1965 Methods of fibre sampling for testing ISO
11、 1973:1995 BS EN ISO 1973:1996 Textile fibres Determination of linear density Gravimetric method and vibroscope method ISO 2602:1980 BS 2846 Guide to statistical interpretation of data Part 2:1981 Estimation of the mean: confidence interval ISO 3060:1974 BS 5116:1974 Method of test for determination
12、 of breaking tenacity of flat bundles of cotton fibres Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN ISO title page, pages 2 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendm
13、ents incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 5079 December 1995 ICS 59.060.20 Descriptors: See ISO document English version Textiles Fibres Determination of breaking force and elongation at break o
14、f individual fibres (ISO 5079:1995) Textiles Fibres Dtermination de la force de rupture et de lallongement la rupture des fibres individuelles (ISO 5079:1995) Textilien Fasern Bestimmung der Hchstzugkraft und Hchstzugkraftdehnung an Spinnfasern (ISO 5079:1995) This European Standard was approved by
15、CEN on1995-09-11. 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 concerning such national standards ma
16、y be obtained on application to the Central Secretariat 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 language and notified to the Cen
17、tral Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CEN European
18、Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1995 All rights of reproduction and communication in any form and by any means reserved in all countries to CEN and its members Ref. No. EN ISO 5079:19
19、95 EEN ISO 5079:1995 BSI 10-1999 2 Foreword The text of the International Standard ISO5079:1995 has been prepared by Technical Committee ISO/TC38, Textiles, in collaboration with CEN/TC248, Textiles and textile products. This European Standard shall be given the status of a national standard, either
20、 by publication of an identical text or by endorsement, at the latest by June1996, and conflicting national standards shall be withdrawn at the latest by June1996. According to CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium,
21、Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the UnitedKingdom.EN ISO 5079:1995 BSI 10-1999 3 1 Scope This International Standard specifies the method and conditions of test for the determination of the
22、breaking force and elongation at break of individual fibres in the conditioned or wet state. The determination of these fibre properties, when carried out on different kinds of testing equipment, will not generally give identical results. To avoid such differences, this International Standard is res
23、tricted to the use of constant-rate-of-extension testing apparatus. The method is applicable to all fibres, including crimped fibres, provided that the length of fibre available enables the initial length specified in this International Standard to be used. NOTE 1For natural fibres (especially wool
24、and cotton) the breaking test most commonly performed is that of bundles of fibres (see ISO3060 and IWTO32-82). 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, t
25、he editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of cu
26、rrently valid International Standards. ISO 139:1973, Textiles Standard atmospheres for conditioning and testing. ISO 1130:1975, Textile fibres Some methods of sampling for testing. ISO 1973:1995, Textile fibres Determination of linear density Gravimetric method and vibroscope method. ISO 2602:1980,
27、Statistical interpretation of test results Estimation of the mean Confidence interval. ISO 3060:1974, Textiles Cotton fibres Determination of breaking tenacity of flat bundles. IWTO 32-82, Determination of the bundle strength of wool fibres, International Wool Textile Organization, Brussels. 3 Defin
28、itions For the purposes of this International Standard, the following definitions apply. 3.1 breaking force maximum force applied to a test specimen carried to rupture during a tensile test under specified conditions (see A 1inFigure 1) Figure 1 Typical force/elongation curveEN ISO 5079:1995 4 BSI 1
29、0-1999 3.2 force at rupture final force just before complete rupture of the test specimen (see B 1inFigure 1) 3.3 extension increase in length of a test specimen, produced by a force on that specimen, expressed in units of length 3.4 elongation ratio of the extension of a test specimen to its initia
30、l length, expressed as a percentage 3.5 elongation at break elongation of a test specimen produced by the breaking force (see A 2inFigure 1) 3.6 elongation at rupture elongation of a test specimen corresponding to rupture (see B 2in Figure 1) 3.7 gauge length distance between two effective clamping
31、points of a testing device 3.8 initial length length of a test specimen under specified pretension at the beginning of a test NOTE 2For a tensile test, the initial length is measured between the two effective clamping points. 3.9 pretension tension applied to a test specimen at the beginning of a te
32、nsile test 3.10 tension force tending to cause the extension of a body NOTE 3In textile testing, the tension applied is based on the linear density or cross-sectional area. 3.11 breaking tenacity breaking force divided by the linear density 4 Principle An individual fibre is extended at a constant r
33、ate until rupture occurs. The elongation of the fibre and the force required are measured. To calculate the breaking tenacity, the linear density of the individual fibres or the mean linear density of the laboratory sample is also required (see ISO1973). 5 Apparatus and reagents 5.1 Tensile testing
34、machine, with suitable clamps for gripping individual fibres at the required initial length, means for stretching the fibre to rupture at constant rate of extension by moving one of the clamps, and means for recording the force applied to the fibre and the corresponding extension (elongation). A dev
35、ice giving a force/extension (tenacity/elongation) curve to indicate whether fibre slippage is occurring in the clamps is useful. A digital display or data-collecting system may be used in addition. Advice on mounting of test specimens is given inAnnex A. 5.1.1 The machine shall be capable of operat
36、ing at various constant rates of extension between at least5mm/min and20mm/min. 5.1.2 The machine shall meet the following requirements of accuracy and repeatability. a) The error in indication of the force shall not exceed1% of the mean breaking force of the specimen. b) The error in indication of
37、the extension shall not exceed 0,1mm. c) The error of the initial length shall not exceed 0,2mm. The constant rate of displacement of the moving clamp shall vary by less than 5%. 5.1.3 The clamps of the machine shall be capable of adjustment, and the surface of the clamp jaws in contact with the spe
38、cimen shall be of a material to provide the correct gripping force without damage to the fibre, thereby avoiding slippage and jaw breaks (see8.5). 5.2 Distilled or deionized water, at a temperature of(20 2) C, to which has been added a nonionic wetting agent to a maximum concentration of0,1%, for us
39、e if wet testing is to be carried out. 6 Conditioning and testing atmospheres The atmospheres for preconditioning, conditioning and testing shall be as specified in ISO139. 7 Sampling To ensure that the laboratory sample is representative of the material and that the test specimen taken from the lab
40、oratory sample is representative of that sample, sampling shall be carried out in accordance with ISO1130.EN ISO 5079:1995 BSI 10-1999 5 8 Procedure 8.1 Condition the test specimens and carry out the tests in one of the standard atmospheres for testing as specified in clause6. 8.2 Adjust the machine
41、 to extend the specimen using a speed of the moving clamp of a) 50 % elongation per minute, for specimens with a mean elongation at break lower than8%, or b) 100 % elongation per minute, for specimens with a mean elongation at break equal to or greater than8%. If the nominal elongation at break is n
42、ot known, establish an approximate value by preliminary tests. In cases where the breaking elongation found in the preliminary test lies around8%, one of the above testing speeds shall be agreed upon by the interested parties. If both linear density and breaking force for the same fibre are required
43、, then the linear density of the fibre shall be determined in accordance with ISO1973 before the tensile test is performed. NOTE 4If the final results vary slightly from those obtained in the preliminary test, a repetition of the test at a different speed is not necessary. 8.3 Prepare and mount an i
44、ndividual fibre (seeAnnex A) under specified pretension in the clamps of the testing machine. For pretensioning, apply a mass piece to the fibre. Ensure that the fibre lies along the axis of extension of the machine. 8.3.1 Use a pretension of (1,0 0,1) cN/tex for the conditioned test and (0,5 0,05)
45、cN/tex for the wet test. For the fibres listed inTable 1, use the pretension values indicated. Table 1 Pretension forces Calculate the mass necessary to obtain the required pretension on the basis of the nominal linear density of the fibre. 8.3.2 Use an initial length of20mm. NOTE 5Where it is impos
46、sible to use the20mm initial length because of short fibre length, then an initial length of10mm may be used. In this case the accuracy of results is reduced. 8.4 After the fibre has been clamped under a specified pretension, set the traversing clamp in motion at the specified testing speed and exte
47、nd the test specimen to rupture, recording the elongation of the fibre and the force required. 8.5 Test at least50 fibres, unless otherwise agreed by the interested parties. Record the number of jaw breaks, i.e. breaks in which none of the broken ends is visible. The condition of the clamps shall be
48、 such that the number of jaw breaks does not exceed20% of the number of specimens tested, otherwise the jaws shall be examined and, if necessary, changed. Ascertain during the test that the clamped fibre length is not spuriously increased by slippage of the fibre in the jaws. This shall be done by i
49、nspection of the recorded curve or the recorded force and corresponding elongation. Results obtained from test specimens showing jaw breaks or fibre slippage in the jaws shall be discarded. 8.6 If a wet test is required, first immerse the test specimens for a period of2min in distilled or deionized water (5.2). With the lower clamp open, mount the wetted test specimen under pretension in the upper clamp. Wet the test specimen again for10s using a glass vessel filled with water (5.2). Then remove the glass v
