1、BRITISH STANDARD AEROSPACE SERIES BS EN 2561:1995 Carbon fibre reinforced plastics Unidirectional laminates Tensile test parallel to the fibre direction The European Standard EN 2561:1995 has the status of a British Standard ICS 49.040.10 UDC 678.6.046:667.494-039.626:620.172.629.7BSEN2561:1995 This
2、 British Standard, having been prepared under the directionof the Engineering SectorBoard, was published underthe authority of the Standards Board and comes intoeffect on 15December1995 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference ACE/64 Draft for
3、 comment 88/72264 DC ISBN 0 580 23109 7 Committees responsible for this British Standard The preparation of this European Standard was entrusted to Technical Committee ACE/64, Aerospace structural reinforced plastics, upon which the following bodies were represented: British Plastics Federation Mini
4、stry of Defence Society of British Aerospace Companies Limited Amendments issued since publication Amd. No. Date CommentsBSEN2561:1995 BSI 09-1999 i Contents Page Committees responsible Inside front cover National foreword ii Foreword 2 Text of EN 2561 3 List of references Inside back coverBSEN2561:
5、1995 ii BSI 09-1999 National foreword This British Standard has been prepared under the direction of the Aerospace Standards Policy Committee and is the English language version of EN2561:1995 Aerospace series Carbon fibre reinforced plastics Unidirectional laminates Tensile test parallel to the fib
6、re direction, published by the European Committee for Standardization (CEN). EN 2561 was produced as a result of international discussions in which the United Kingdom took an active part. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Stan
7、dards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references Publication referred to Corresponding British Standard EN 2744:1992 BS EN 2744:1992 Non-metallic materials Preferred test temperatures S
8、ummary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 10, an inside back cover 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
9、table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2561 September 1995 ICS 49.040.10 Descriptors: Aircraft industry, laminates, reinforced plastics, carbon fibres, thermosetting resins, tension tests English version Aerospace series Carbon fibre reinforced plastics
10、Unidirectional laminates Tensile test parallel to the fibre direction Srie arospatiale Plastiques renforcs de fibres de carbone Stratifis unidirectionnels Essai de traction paralllement la direction des fibres Luft und Raumfahrt Kohlenstoffaserverstrkte Kunststoffe Unidirektionale Laminate Zugprfung
11、 parallel zur Faserrichtung This European Standard was approved by CEN on1995-09-19. 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 a
12、nd bibliographical references concerning such national standards may 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 responsib
13、ility of a CEN member into its own language and notified to the Central 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, Po
14、rtugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1995 Copyright reserved to CEN members Ref. No. EN 2561:1995 EEN2561:1995 BSI 09-19
15、99 2 Foreword This European Standard has been prepared by the European Association of Aerospace Manufacturers (AECMA). After inquiries and votes carried out in accordance with the rules of this Association, this Standard has successively received the approval of the National Associations and the Off
16、icial Services of the member countries of AECMA, prior to its presentation to CEN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March1996, and conflicting national standards shall be withdrawn
17、at the latest by March1996. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switze
18、rland and United Kingdom. Contents Page Foreword 2 1 Scope 3 2 Normative references 3 3 Definitions 3 4 Principle 4 5 Apparatus 4 6 Specimens 4 7 Procedure 4 8 Expression of results 5 9 Designation 7 10 Test report 7 Annex A (normative) Form, dimensions of specimen, test fixture 8 Figure 1 6 Figure
19、A.1 Specimen and test fixture, types A and B 8 Figure A.2 Specimen and test fixture, type C 8 Table A.1 9EN2561:1995 BSI 09-1999 3 1 Scope This standard specifies the method of determination of the ultimate tensile strength, tensile modulus and, if required, the Poissons ratio and strain at failure
20、in tension of carbon fibre reinforced plastics in the form of unidirectional laminates. This method is only applicable to specimens where the axis is parallel to the direction of the fibres. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from oth
21、er publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or
22、 revision. For undated references the latest edition of the publication referred to applies. EN 2489, Aerospace series Fibre reinforced plastics Determination of the action of test fluids. EN 2565, Aerospace series Preparation of carbon fibre reinforced resin panels for test purposes 1) . EN 2743, A
23、erospace series Reinforced plastics Standard procedures for conditioning prior to testing 1) . EN 2744, Aerospace series Non-metallic materials Preferred test temperatures. EN 2823, Aerospace series Fibre reinforced plastics Test method for the determination of the effect of exposure to humid atmosp
24、here on physical and mechanical characteristics 1) . 3 Definitions For the purposes of this standard, the following definitions apply: 3.1 tensile stress tensile load experienced by the specimen at any moment during the test, per initial unit cross sectional area within the free length 3.2 ultimate
25、tensile strength ( T11 ) tensile stress at the moment failure occurs 3.3 ultimate tensile strength related to the fibre ( f ) the ultimate tensile strength calculated as a function of the fibre cross sectional area and based on the hypothesis that all the tensile load is carried by the fibres 3.4 st
26、rains ( 11and 22 ) change in the distance between reference points in the specimen free length, produced by a tensile load and expressed with respect to the initial distance between these points 11is the strain measured parallel to the fibre direction 22is the strain measured perpendicular to the fi
27、bre direction (in the plane of the laminate) 3.5 percentage strain to failure (A %) increase in the distance between reference points in the specimen free length, produced by a tensile load and expressed as a percentage of the initial distance between these points and measured at the moment of failu
28、re 1) Published as AECMA Prestandard at the date of publication of this standardEN2561:1995 4 BSI 09-1999 3.6 secant modulus between P R /10 and P R /2 (E T11 ) slope of the straight line passing through: the point of the stress/strain diagram parallel to the load axis, corresponding to a stress cal
29、culated from P R /2; the point on the same diagram corresponding to a stress calculated from P R /10. P Ris the load at failure of the specimen 3.7 secant modulus related to the fibre (E f ) the secant modulus calculated as a function of the fibre cross sectional area and based on the hypothesis tha
30、t all the tensile load is carried by the fibres 3.8 poissons ratio (v 12 ) absolute value of the ratio of the difference in strain 22to the difference in strain 11 , measured between P R /10 and P R /2 (see Figure 1) 4 Principle The method consists of the measurement of the longitudinal and, if requ
31、ired, the lateral strains in the material, in relation to the load applied, during a tensile test carried out at a constant rate of displacement until failure occurs. 5 Apparatus 5.1 Micrometer with6mm diameter flat faces and accurate to0,01mm 5.2 Testing machine, accurate to within1% in the load ra
32、nge used 5.3 A means of recording strains, in relation to the load (extensometer or strain gauges), accurate to within1% in the strain range used. The instrument shall not mark the specimen in a way which may cause premature failures. 5.4 If necessary, heated cabinet, regulated so as to conform to E
33、N2744 for tests at temperatures other than ambient 5.5 Thermocouple and recorder for tests at temperatures other than ambient 6 Specimens Take specimens from panels prepared according to EN2565. 6.1 Form and dimensions See Annex A. 6.2 Number Minimum of five 7 Procedure 7.1 Conditioning EN 2743 for
34、tests in the initial state; EN 2489 for tests after immersion; EN 2823 for tests after humidity exposure. 7.2 Tests 7.2.1 Measure the width to within0,01mm in the centre of the specimen and at two opposite points located30mm from the centre. b is the arithmetic mean of these three measurements.EN256
35、1:1995 BSI 09-1999 5 Measure the thickness to within0,01mm in the centre of the specimen and at two opposite points on the specimen axis and located30mm from the centre. h is the arithmetic mean of these three measurements. 7.2.2 For tests at temperatures other than ambient, the period separating th
36、e conditioning and start of the test shall conform to the following conditions: For specimens which have not been aged or subjected to immersion, the exposure time at the test temperature shall be established by preliminary tests. For specimens subjected to immersion, see EN2489. For humidity aged s
37、pecimens, see EN2823. 7.2.3 The alignment of the specimen in the test machine jaws shall be sufficient to avoid the introduction of any bending loads. 7.2.4 The jaws shall entrap the tabs of the specimens of types A and B (see Figure A.1). 7.2.5 The load shall be applied at a constant rate of jaw se
38、paration of2mm/min. 7.2.6 Record the strain 11and, if necessary, the strain 22using the extensometer or strain gauges as a function of load. 7.2.7 Record the load at failure P Rand, if necessary, the strain at failure ( 11 ) R . 8 Expression of results 8.1 Ultimate tensile strength T11(MPa) where: 8
39、.2 Ultimate tensile strength related to the fibre f (MPa) where: P R is the load at failure, in newtons; b is the width, in millimeters; h is the thickness, in millimeters. n is the number of plies; M sf is the mass per unit area of fibre, in grams per square meter, per ply; f is the density of fibr
40、e, in kilograms per cubic meter; P R is the load at failure, in newtons; b is the width, in millimeters. T11 P R bh - = f P R f nbM sf - =EN2561:1995 6 BSI 09-1999 8.3 Secant modulus E T11(MPa) between P R /10 and P R /2 Determine the strains from the recorded load/strain diagram (Figure 1): where:
41、8.4 Secant modulus E f(MPa) between P R /10 and P R /2 related to the fibre where: Figure 1 P R is the load at failure, in newtons; b is the width, in millimeters; h is the thickness, in millimeters; ( 11 ) A is the strain parallel to the fibre direction corresponding to P R /10; ( 11 ) B is the str
42、ain parallel to the fibre direction corresponding to P R /2. P R is the load at failure, in newtons; n is the number of plies; f is the density of fibre, in kilograms per cubic meter; M sf is the mass per unit area of fibre, in grams per square meter; b is the width, in millimeters;EN2561:1995 BSI 0
43、9-1999 7 8.5 Poissons ratio 12 where: 8.6 Percentage strain to failure A % A % = 100 ( 11 ) R ( 11 ) R= strain to failure parallel to the fibre direction 8.7 Validity The failure shall occur within the free length of the specimen but may extend under the end tabs or within the test machine jaws. 9 D
44、esignation EXAMPLE: 10 Test report It shall include the following: designation (see9); all data ensuring the traceability of the material (trade mark, identification, marking, date of receipt etc.); all information regarding specimen preparation; specimen dimensions; test conditions, for example tes
45、t temperature, relative humidity if these differ from this standard; exposure time at the test temperature; load/strain diagram; ultimate tensile strength T11and mode of failure; method of strain measurement (extensometer or strain gauges); secant modulus E T11between P R /10 and P R /2; Poissons ra
46、tio 12(if required); ultimate tensile strength related to the fibre f(if required); secant modulus E fbetween P R /10 and P R /2 related to the fibre (if required); percentage strain to failure A (%); individual values, arithmetic mean and standard deviation; any incident which may have affected the
47、 results. ( 11 ) A is the strain parallel to the fibre direction corresponding to P R /10; ( 11 ) B is the strain parallel to the fibre direction corresponding to P R /2. ( 11 ) A is the strain parallel to the fibre direction corresponding to P R /10; ( 11 ) B is the strain parallel to the fibre dir
48、ection corresponding to P R /2; ( 22 ) A is the strain perpendicular to the direction corresponding to P R /10; ( 22 ) B is the strain perpendicular to the direction corresponding to P R /2.EN2561:1995 8 BSI 09-1999 Annex A (normative) Form, dimensions of specimen, test fixture See Figure A.1 andFig
49、ure A.2 andTable A.1. The dimensions are expressed in millimetres. Figure A.1 Specimen and test fixture, types A and B Figure A.2 Specimen and test fixture, type CEN2561:1995 BSI 09-1999 9 Table A.1 Symbol Specimen type A b B b C c b 10 0,5 15 0,5 15 0,5 h a 2 0,2 1 0,2 1 0,2 a If the ply thickness causes any uncertainty regarding the number of layers necessary to o
