1、BRITISH STANDARD BS ISO 11566: 1996 Implementation of ISO 11566:1996 Carbon fibre Determination of the tensile properties of single-filament specimens ICS 59.100.20BSISO 11566:1996 This British Standard, having been prepared under the directionof the Sector Board for Materials and Chemicals, was pub
2、lished under the authority of the Standards Board and comes into effect on 15 December 1996 BSI 11-1998 The following BSI references relate to the work on this standard: Committee reference PRI/42 Draft for comment 94/303769 DC ISBN 0 580 26815 2 Committees responsible for this British Standard The
3、preparation of this British Standard was entrusted to Technical Committee PRI/42, Fibre reinforced thermosetting plastics and prepregs, upon which the following bodies were represented: BEAMA Ltd. British Plastics Federation Chemical Industries Association Department of the Environment (Building Res
4、earch Establishment) Department of Trade and Industry (National Physical Laboratory) European Resin Manufacturers Association Ministry of Defence Motor Industry Research Association RAPRA Technology Ltd. Society of Motor Manufacturers and Traders Ltd. Amendments issued since publication Amd. No. Dat
5、e CommentsBS ISO 11566:1996 BSI 11-1998 i Contents Page Committees responsible Inside front cover National foreword ii Foreword iii Text of ISO 11566 1BSISO 11566:1996 ii BSI 11-1998 National foreword This British Standard reproduces verbatim ISO 11566:1996 and implements it as the UK national stand
6、ard. This British Standard is published under the direction of the Sector Board for Materials and Chemicals whose Technical Committee PRI/42 has the responsibility to: aid enquirers to understand the text; present to the responsible international committee any enquiries on interpretation, or proposa
7、ls for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. NOTEInternational and European Standards, as well as overseas standards, are available from Customer Services, BSI, 389 Chiswick High Road, London W4 4AL. A British S
8、tandard 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 not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cov
9、er, an inside front cover, pages i and ii, the ISO title page, pages ii to iv, pages 1 to 5 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.BSISO11566:1996 ii BSI 11
10、-1998 Contents Page Foreword iii 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Principle 1 5 Apparatus and materials 1 6 Test specimens 1 7 Procedure 2 8 Expression of results 3 9 Precision 4 10 Test report 4 Annex A (normative) Determination of system compliance 5 Figure 1 Mounting for singl
11、e-filament test specimen 2 Figure 2 Relationship between force and extension during a tensile test 4 Figure A.1 Determination of system compliance K 5 Table 1 Selection of strain limits 4BSISO11566:1996 BSI 11-1998 iii Foreword ISO (the International Organization for Standardization) is a worldwide
12、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 c
13、ommittee. 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. Draft International Standards adopted by th
14、e 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. International Standard ISO 11566 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 13, Compos
15、ites and reinforcement fibres. Annex A forms an integral part of this International Standard.iv blankBS ISO 11566:1996 BSI 11-1998 1 1 Scope This International Standard specifies a method of test for the determination of the tensile properties of a single-filament specimen. The method is applicable
16、to single filaments of carbon fibres, taken from multifilament yarns, strands, tows, staple fibres, staple yarns, woven fabrics, braids and knits. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Stan
17、dard. At the time of publication, the 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 I
18、EC and ISO maintain registers of currently valid International Standards. ISO 291:1977, Plastics Standard atmospheres for conditioning and testing. ISO 527-1:1993, Plastics Determination of tensile properties Part 1: General principles. ISO 10548:1994, Carbon fibre Determination of size content. ISO
19、 10618: 1) , Carbon fibre Determination of tensile properties of resin-impregnated yarns. ISO 11567:1995, Carbon fibre Determination of filament diameter and cross-sectional area. 3 Definitions For the purposes of this International Standard, the definitions given in ISO 527-1 apply, together with t
20、he following. 3.1 system compliance: that portion of the indicated extension contributed by the load train system and the specimen-gripping system 3.2 specimen mounting: a thin sheet made of paper, metal or plastic with a slot whose length corresponds to the gauge length of a test specimen 4 Princip
21、le A single-filament specimen is loaded in tension at a constant speed by a suitable mechanical testing machine until failure and the force-extension curve recorded. The tensile strength and tensile modulus of elasticity are calculated from the force-extension relationship and the specimen cross-sec
22、tional area. The tensile modulus of elasticity is calculated by dividing the difference in stress at two defined points by the corresponding difference in strain at these points, which may be two stress levels (method A) or two strain levels (method B). The difference in strain is corrected for the
23、system compliance. The cross-sectional area is determined independently. The relationship between stress and strain may not be linear, hence a chord modulus has to be defined. The two methods (A and B) represent two distinct methods of defining the position of the chord and may not give identical re
24、sults. 5 Apparatus and materials 5.1 Tensile-testing machine, operating at a constant crosshead speed, equipped with force- and extension-recording devices. The accuracy of the force indication shall be better than 1 % of the recorded value. The movement of the crosshead shall be recorded in order t
25、o calculate the specimen extension. The grips shall have flat surfaces. 5.2 Specimen mounting, made from a thin sheet of paper, flexible metal or plastic, with slot of length25 mm 0,5 mm, as shown in Figure 1. The sheet shall be as thin as possible in order to minimize misalignment of the specimen a
26、t the grips. A thickness of 0,1 mm is recommended 5.3 Adhesive: any epoxy resin, rosin or sealing wax which is suitable for bonding the filament firmly to the mounting. 5.4 Adhesive tape, to fix the filament temporarily to the mounting (no special requirements). 6 Test specimens Prepare at least 20
27、test specimens from each elementary unit, to enable 20 measurements to be made for each result reported. Removal of any size present makes it easier to prepare good specimens. To remove the size, use the solvent-extraction, chemical-digestion or pyrolysis methods specified in ISO 10548. 1) To be pub
28、lished.BS ISO 11566:1996 2 BSI 11-1998 7 Procedure 7.1 Test atmosphere Carry out the test in one of the standard atmospheres defined in ISO 291. 7.2 Measurement of cross-sectional area 7.2.1 Measure the cross-sectional area of the filaments independently by one of the methods given in ISO 11567 (mic
29、roscopic determination for transversely cut specimens; calculation from the number of filaments, density and linear density of the yarns; calculation from the diameter as determined by optical microscopy; or calculation from the diameter as determined by laser diffractometry). When the cross-section
30、al area is determined from the diameter measured by optical microscopy or laser diffractometry, the same test specimens can be used for the measurement of both cross-sectional area and tensile properties. 7.2.2 In cases where the cross-sectional area of the fibres is known to vary widely within a gi
31、ven fibre bundle or tow, ensure, if judged necessary, that the tensile strength is determined on filaments for which the cross-sectional area has been measured. In this case, prepare the test specimens and determine the cross-sectional area in accordance with ISO 11567 using optical microscopy or la
32、ser diffractometry. Take care when measuring the cross-sectional area to avoid damage to the filaments. 7.3 Tensile testing 7.3.1 System compliance The system compliance K is a correction coefficient applied to the indicated extension to correct for the contribution from the load train system and th
33、e specimen-gripping system (see 3.1) and hence give the true specimen gauge-length extension. The procedure for the determination of the system compliance is given in annex A. Determine the system compliance experimentally for each combination of test machine conditions, grip system and specimen mou
34、nting. Subtract the compliance from the indicated extension to give the true specimen gauge-length extension see 8.2, equations (2) and (3). Check the compliance at regular intervals as recommended in the product specification or by the person requesting the test. 7.3.2 Performing the test 7.3.2.1 P
35、lace a single-filament specimen over the centre of the slot of a mounting (5.2). Temporarily fix one end of the specimen to the mounting with a piece of adhesive tape (5.4). Lightly stretch the specimen across the slot and fix the other end to the other end of the mounting with a piece of adhesive t
36、ape. 7.3.2.2 Apply a drop of adhesive (5.3) to the specimen at each end of the mounting slot to bond the specimen firmly in place. 7.3.2.3 Set the crosshead speed of the tensile testing machine (5.1) to a value between 1 mm/min and 5 mm/min. Figure 1 Mounting for single-filament test specimenBS ISO
37、11566:1996 BSI 11-1998 3 7.3.2.4 Clamp the mounting in the grips so that the specimen is aligned with the loading axis of the test machine. 7.3.2.5 Before applying the load, i.e. with the mounting unstrained, cut or burn through both sides of the mounting at mid-gauge. If burning is used, care must
38、be taken to avoid exposing the specimen to the flame. As the filament is very fragile, the specimen breaks occasionally during this step. 7.3.2.6 Start the recording equipment and load the test specimen to failure. 7.3.2.7 If the test specimen fails within the grips, discard the result and repeat wi
39、th a fresh specimen. 8 Expression of results 8.1 Tensile strength For each test specimen, calculate the tensile strength s f , expressed in megapascals, of the filament using the equation where 8.2 Tensile modulus of elasticity 8.2.1 Method A (see Figure 2) In this method, the tensile modulus of ela
40、sticity E f,Aexpressed in gigapascals, is calculated using the equation where 8.2.2 Method B (see Figure 2) In this method, the tensile modulus of elasticity E f,Bexpressed in gigapascals, is calculated using the equation where . . . (1) F f is the maximum tensile force, in newtons; A f is the cross
41、-sectional area, in square millimetres, of the filament (see 7.2). .(2) DF A is the difference in force, in newtons, corresponding to load limits of 400 mN/tex and 800 mN/tex; A f is the cross-sectional area, in square millimetres, of the filament (see 7.2); L is the gauge length, in millimetres, of
42、 the specimen; DL A is the difference in length, in millimetres, corresponding to load limits of 400 mN/tex and 800 mN/tex; K is the system compliance, in millimetresper newton, calculated in accordance with annex A. .(3) DF B is the difference in force, in newtons, corresponding to the strain limit
43、s selected, depending on the nominal strain at break of the fibre, as specified in Table 1; A f is the cross-sectional area, in square millimetres, of the filament (see 7.2); L is the gauge length, in millimetres, of the specimen; DL B is the difference in length, in millimetres, corrresponding to t
44、he strain limits selected, depending on the nominal strain at break of the fibre, as specified in Table 1; K is the system compliance, in millimetresper newton.BS ISO 11566:1996 4 BSI 11-1998 9 Precision The precision of this method is not known because interlaboratory data are not available. Interl
45、aboratory data are being obtained and a precision statement will be added at the following revision. Table 1 Selection of strain limits 10 Test report The test report shall include the following particulars: a) a reference to this International Standard; b) all details necessary for identification o
46、f the fibre sample tested; c) the cross-sectional area of the filament and the method used to determine it; d) the adhesive used; e) the crosshead speed used in the tensile test; f) the system compliance K; g) the number of specimens tested, including the number of specimens discarded; h) the indivi
47、dual and mean values of the tensile strength and tensile modulus of elasticity; i) the method used to calculate the tensile modulus of elasticity, i.e. method A or B; j) the date of the test; k) the atmospheric conditions used in the test; l) any deviation from the procedure specified likely to have
48、 had a bearing on the results. Figure 2 Relationship between force and extension during a tensile test Value in percent Nominal strain at break, e Strain limits 1,2 e 0,1 to 0,6 0,6 e 1,2 0,1 to 0,3 0,3 e 0,6 0,05 to 0,15 NOTEThe nominal strain at break (or percent elongation atmaximum load) of comm
49、ercially available products may be calculated from the nominal tensile strength and tensile modulus of elasticity values for the type of carbon fibre undertest.BS ISO 11566:1996 BSI 11-1998 5 Annex A (normative) Determinationofsystem compliance A.1 Prepare specimen mountings (5.2) with slots of different lengths, in order to produce test specimens of different gauge lengths. These mountings shall all be of the same material and differ only in overall length and slot length. Use slot lengths such as5mm, 10 mm, 20 mm, 30 mm and 40 mm, p
