1、Aerospace series - Carbon fibre thermosetting resin - Unidirectional laminates - Compression test parallel to fibre directionBS EN 2850:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2850 October 2017 ICS 49.0
2、25.40 English Version Aerospace series - Carbon fibre thermosetting resin - Unidirectional laminates - Compression test parallel to fibre direction Srie arospatiale - Fibres de carbone/rsine thermodurcissable - Stratifis unidirectionnels - Essai de compression paralllement au sens des fibres Luft- u
3、nd Raumfahrt - Unidirektionale Laminate aus Kohlenstoffasern und Reaktionsharz - Druckversuch parallel zur Faserrichtung This European Standard was approved by CEN on 26 June 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving thi
4、s 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 v
5、ersions (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 Austr
6、ia, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain
7、, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide
8、for CEN national Members. Ref. No. EN 2850:2017 ENational forewordThis British Standard is the UK implementation of EN 2850:2017.The UK participation in its preparation was entrusted to Technical Committee ACE/65, Non-metallic materials for aerospace purposes.A list of organizations represented on t
9、his committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 98010 7IC
10、S 49.025.40Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN
11、 2850:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 2850 October 2017 ICS 49.025.40 English Version Aerospace series - Carbon fibre thermosetting resin - Unidirectional laminates - Compression test parallel to fibre direction Srie arospatiale - Fibres de carbone/rsine thermodurcissable -
12、Stratifis unidirectionnels - Essai de compression paralllement au sens des fibres Luft- und Raumfahrt - Unidirektionale Laminate aus Kohlenstoffasern und Reaktionsharz - Druckversuch parallel zur Faserrichtung This European Standard was approved by CEN on 26 June 2017. CEN members are bound to compl
13、y 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 may be obtained on application to the CEN-CENELEC
14、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 translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the sam
15、e status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg,
16、 Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brus
17、sels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 2850:2017 EBS EN 2850:2017EN 2850:2017 (E) 2 Contents Page European foreword 3 1 Scope 4 2 Normative references 4 3 Principle of the method 5 4 Terms and definitions . 5 5 D
18、esignation . 6 6 Test pieces . 6 7 Apparatus. 8 8 Conditioning 8 9 Procedure 8 10 Calculation of results . 9 11 Validity 11 12 Test report . 12 Annex A (normative) 13 Annex B (normative) 15 Annex C (informative) . 16 BS EN 2850:2017EN 2850:2017 (E) 3 European foreword This document (EN 2850:2017) ha
19、s been prepared by the Aerospace and Defence Industries Association of Europe - Standardization (ASD-STAN). After enquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the me
20、mber countries of ASD, 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 April 2018, and conflicting national standards shall be withdrawn at the latest by April 20
21、18. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the fo
22、llowing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands
23、, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 2850:2017EN 2850:2017 (E) 4 1 Scope This European Standard defines a method for the determination of stress at failure and Youngs modulus in compression of carbon thermos
24、etting resin unidirectional laminates. The method only covers test pieces the axis of which is parallel to the fibre direction. This method covers fibres (or fabrics) other than carbon, when the relevant technical specification explicitly mentions it. 2 Normative references The following documents,
25、in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 2372 1), Nuts, hexagon, thin,
26、 steel, cadmium plated Classification: 1 100 MPa/235 C Aerospace series 2)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 3)EN 2743, Aerospace series Fibre r
27、einforced plastics Standard procedures for conditioning prior to testing unaged materials EN 2744, Aerospace series Non-metallic materials Preferred test temperatures EN 2823, Aerospace series Fibre reinforced plastics Determination of the effect of exposure to humid atmosphere on physical and mecha
28、nical characteristics 3)EN 2859, Aerospace series Bolts, normal hexagonal head, close tolerance normal shank, short thread, in alloy steel, cadmium plated, metric series Classification: 1 100 MPa (at ambient temperature) / 235 C EN 3228, Aerospace series Nuts, hexagonal, plain, reduced height, norma
29、l across flats, in steel, cadmium plated Classification: 900 MPa (at ambient temperature) / 235 C EN 3783, Aerospace series Fibre composite materials Normalisation of fibre dominated mechanical properties 1) Inactive for new design, see prEN 3228. 2) Published as ASD-STAN Standard at the date of pub
30、lication of this standard by AeroSpace and Defence industries Association of Europe - Standardization (ASD-STAN) (www.asd-stan.org) 3) Published as ASD-STAN Prestandard at the date of publication of this standard by AeroSpace and Defence industries Association of Europe - Standardization (ASD-STAN)
31、(www.asd-stan.org) BS EN 2850:2017EN 2850:2017 (E) 5 3 Principle of the method The method consists in recording and measuring the longitudinal strain of the material as a function of the applied load during a compression test carried out at a constant rate until failure. The load applied to the mate
32、rial may be introduced in two different ways: either mainly in shear through co-cured or bonded tabs (Method A); or exclusively in compression by direct end loading of the test piece (Method B). It is important to note that the test results obtained using different test pieces are not comparable. 4
33、Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1 compression stress at any point in time during the test (c) compression load per initial unit cross-sectional area in the gauge length sustained by the test piece at any point in time during the t
34、est 4.2 compression stress at failure (c11) compression stress at the moment of failure Note 1 to entry: It is calculated using the formula given in 10.1. 4.3 strain (11) change in the distance between reference points within the gauge length of the test piece produced by a compression load expresse
35、d in relation to the original distance between these points Note 1 to entry: 11 is the strain measured parallel to the fibre axis. 4.4 secant compression modulus two methods of calculation are possible Note 1 to entry: The one based on strain shall be preferred. Note 2 to entry: Otherwise, the one b
36、ased on the forces shall be used. 4.5 secant compression modulus Ec11(, ) slope of the straight line passing through the stress/longitudinal strain diagram at a point corresponding to % strain with respect to the gauge length of the test piece and a point corresponding to % strain on the same diagra
37、m Note 1 to entry: and are defined in the material standard. Note 2 to entry: In the absence of a material standard, = 0,1 % and = 0,5 % shall be chosen. Note 3 to entry: It is calculated using the formula in 10.2.1. BS EN 2850:2017EN 2850:2017 (E) 6 4.6 secant compression modulus Ec11(PR/10, PR/2)
38、slope of the straight line passing through the stress/longitudinal strain diagram at a point corresponding to a stress calculated from PR/10, and a point corresponding to a stress calculated from PR/2, where PRis the load at failure of the test piece Note 1 to entry: It is calculated using the formu
39、la in 10.2.2. 5 Designation Designation of the method shall be in accordance with the following example: EN2850A Number of this standard Type of test piece (see 6.2) 6 Test pieces 6.1 Preparation of test panels Test panels shall be prepared according to EN 2565. Manufacturing parameters, such as env
40、ironmental products, curing cycle, etc. shall comply with the applicable technical specification. 6.2 Shape and dimension Two types of test pieces are given: Type A (see example in Annex A); Type B (see example in Annex B). Alternatives to type A are possible if they satisfy the following requiremen
41、ts: Gauge length g = (10 0,25) mm; Thickness h = (2 0,2) mm; Total thickness H = (4,5 0,5) mm; Width b = (10 0, 2) mm; Tab length t = 50 mm; Distance between grips K = (13 0,1) mm. BS EN 2850:2017EN 2850:2017 (E) 7 Key 1 Detail of the encircled area Figure 1 Angle of misalignment of the fibres with
42、respect to the compression loading axis shall be less than 0,5. 6.3 Tabs 6.3.1 Bonded tabs In the case of bonded tabs, a check shall be made that the temperature of the bonding cycle does not induce any undesirable post-curing effect in the laminate. The material forming the tabs shall preferably be
43、 the same as that of the test pieces. It is preferable to form the tabs in a co-curing operation when testing at high temperature and/or after humidity ageing. 6.3.2 Integral tabs The test piece is made up of n plies at 0 at its center and of m plies at 45 each side of the plies at 0. n is such that
44、 n plies are 2,25 mm to 2,5 mm thick. m is such that (n + 2 m) plies are 4 mm to 5 mm thick. The integral tabs are machined to provide the gauge length of the test piece (see Annex A - Test pieces A2/A4). NOTE Where the grips slip, a ply of dry glass may be added to the surface of the tabs, prior to
45、 the curing of the panel. 6.4 Number The number of test pieces to be used is defined in the technical specification. If it is not the case, five (5) test pieces shall be used. BS EN 2850:2017EN 2850:2017 (E) 8 7 Apparatus 7.1 Micrometer with flat faces 6 mm in diameter, accurate to within 0,01 mm 4)
46、. 7.2 Test machine accurate to within 1 % in the load range used. 7.3 In order to avoid any buckling, which would affect the test, an accurate alignment shall be ensured in a suitable way. An example of grip alignment guidance is given in Annex A or B and C. 7.4 Device for recording strain as a func
47、tion of load accurate to within 1 % in the strain range used. This equipment shall not produce marks on the test piece likely to cause premature failures. The chosen device shall allow any possible buckling during the test to be detected by the separate recording of the strain on each face of the te
48、st piece (e g. strain gauges). 7.5 If required, a controlled temperature cabinet and recording thermocouple may be used for tests at temperatures (in accordance with EN 2744) other than ambient. 8 Conditioning Where testing is carried out in the initial state, conditioning shall be in accordance wit
49、h EN 2743. Where testing is carried out after immersion, conditioning shall be in accordance with EN 2489. Where testing is carried out after exposure to humid heat, conditioning shall be in accordance with EN 2823. 9 Procedure 9.1 Measure the thickness twice to the nearest 0,01 mm and the width to the nearest 0,01 mm in the gauge length of the test piece. 9.2 Position the strain measuring device (see 7.4) on the test piece. 9.3 For tests at a temperature other than
