1、BSI Standards PublicationBS EN 6031:2015Aerospace series Fibrereinforced plastics Testmethod Determination of in-plane shear properties ( 45tensile test)BS EN 6031:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 6031:2015.The UK participation in its prepara
2、tion was entrusted to TechnicalCommittee ACE/65, Non-metallic materials for aerospace purposes.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsibl
3、e for its correctapplication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 86120 8ICS 49.025.40Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Polic
4、y and Strategy Committee on 30 November 2015.Amendments/corrigenda issued since publicationDate Text affectedBS EN 6031:2015EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORMEN 6031 November 2015 ICS 49.025.40 English Version Aerospace series - Fibre reinforced plastics - Test method -Determination o
5、f in-plane shear properties ( 45 tensile test) Srie arospatiale - Matires plastiques renforces de fibres - Mthode dessai - Dtermination des proprits en cisaillement plan (traction il 45) Luft- und Raumfahrt - Faserverstrkte Kunststoffe - Prfverfahren - Bestimmung der Schubeigenschaften ( 45 Zugversu
6、ch) This European Standard was approved by CEN on 21 June 2014. 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 re
7、ferences 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 versions (English, French, German). A version in any other language made by translation under the responsibility of a
8、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 Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedo
9、nia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROP
10、ISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 6031:2015 EBS EN 6031:2015EN 6031:2015 (E) 2 Contents PageEuropean foreword . 3 1 Scope
11、 4 2 Normative references 4 3 Terms and definitions . 4 4 Principle of the method 5 5 Designation of the method . 5 6 Apparatus . 5 7 Test specimen . 6 8 Procedure. 7 9 Presentation of the results 8 10 Test report . 8 BS EN 6031:2015EN 6031:2015 (E) 3 European foreword This document (EN 6031:2015) h
12、as 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 m
13、ember 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 May 2016, and conflicting national standards shall be withdrawn at the latest by May 2016.
14、 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 responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national standards organizatio
15、ns of the following 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,
16、 Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 6031:2015EN 6031:2015 (E) 4 1 Scope This European Standard specifies the procedure for the determination of the in-plane shear strength and modulus of fibre composite
17、s. The procedure is based on the uni-axial tensile stress-strain response of a 45 laminate which is symmetrically laminated about the mid-plane. This standard is applicable to composite laminates manufactured from unidirectional tape or woven fabric reinforcement. This standard does not give any dir
18、ections necessary to meet the health and safety requirements. It is the responsibility of the user of this standard to consult and establish appropriate health and safety precautions. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and
19、 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 2374, Aerospace series Glass fibre reinforced mouldings and sandwich composites Production of tes
20、t panels 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, Aerospace series Fibre reinforced plastics Standard procedures for conditioning prior to
21、testing unaged materials EN 2823, Aerospace series Fibre reinforced plastics Test method for the determination of the effect of exposure to humid atmosphere on physical and mechanical characteristics 1)3 Terms and definitions For the purposes of this document, the following terms and definitions app
22、ly. 3.1 tensile stress at a given moment during the test longitudinal tensile load experienced by the test specimen at a particular moment during the test, divided by the initial unit cross sectional area within the gauge length 3.2 shear stress at a given moment during the test the shear stress is
23、defined as the in-plane shear stress with its principal direction under 45 with the direction in which the tension load is applied, and its magnitude is half of the tensile stress 3.3 shear strength the shear strength is the maximum occurring shear stress during the test. For calculation see 9.1. 1)
24、 Published as ASD-STAN Prestandard at the date of publication of this standard. http:/www.asd-stan.org/BS EN 6031:2015EN 6031:2015 (E) 5 3.4 tensile strain variation in the longitudinal or transverse distance between points within the test specimen gauge length, produced by a tensile load and expres
25、sed with respect to the initial distance between the points (0is the longitudinal strain, its value is positive; 90is the transverse strain of a tensile specimen, its value is negative) 3.5 shear modulus slope of the straight line in a shear stress/strain diagram through the points corresponding wit
26、h two longitudinal strain limits. Unless otherwise defined these longitudinal strains are (0)1= 500 10-6and (0)2= 2 500 10-6(see Figure 3). For calculation see 9.2. 4 Principle of the method Through the use of relations derived from laminated plate theory, expressions are presented which allow the i
27、n-plane 0 shear stress-strain curve to be generated from a uniaxial tension test of a 45 laminate. Experimental test data from a tensile test are used for generating the shear strength and modulus. 5 Designation of the method The designation of the used method shall be drawn up according to the foll
28、owing example. Description block Fibre reinforced plastics, determination of in-plane shear properties ( 45 tensile test) Identity block EN6031 Number of this standard 6 Apparatus 6.1 Tensile testing machine, accurate to within 1 %, in the load range used. 6.2 Flat face micrometer accurate to the ne
29、arest 0,01 mm. 6.3 Vernier caliper accurate to the nearest 0,1 mm. 6.4 This procedure requires load strain data in both the longitudinal and transverse directions. This is accomplished by instrumenting the specimen with longitudinal and transverse strain gauges (5 mm to 10 mm gauge length). The gaug
30、es, surface preparation, and bonding agents should be chosen to provide for optimal performance on the subject material, and suitable automatic strain recording equipment shall be employed. If available, a bi-directional extensometer or a combination of longitudinal and a transverse extensometer can
31、 be used. The extensometers shall be accurate to within 1 % in the applied load range. 6.5 Temperature measuring equipment accurate to 0,2 C at the applied test temperature. 6.6 Vacuum bag sealant material. 6.7 Timer/clock. BS EN 6031:2015EN 6031:2015 (E) 6 7 Test specimen 7.1 Test specimen descript
32、ion The test specimen can consist of either unidirectional tape or woven fabric. Eight plies oriented at + 45 and 45 to the longitudinal axis are applied: (+ 45, 45, + 45, 45) s. To avoid distortions and induced bending the lay-up shall be fully symmetrical. See Figure 1 for dimensions and tolerance
33、s of test specimen. 7.2 Test specimen preparation The specimens are cut out of plates. The coefficient of variation in thickness measurements shall be smaller than 2 % per plate. The lay-up shall be alternatively at + 45 and 45 and symmetrical (see 7.1). The accuracy of the orientation of the fibres
34、 shall be within 2,5. Carbon plates shall be produced according to EN 2565, glass plates in accordance with EN 2374. The process parameters such as bleeders, curing temperature and time, etc. shall be in accordance with the applicable technical specification. All the specimens shall have a 45 lay-up
35、 with respect to the specimen axis. Precautions shall be taken to avoid notches, undercuts, rough or uneven surfaces after machining. 7.3 Strain gauges If strain gauges (see 6.4) are applied for modulus determination, they shall be attached at the centre of the specimen in the longitudinal (0) and i
36、n the transverse (90) direction. 7.4 Tabs The specimen shall have tabs (see Figure 1), either by using precured tabs made by two plies of fabric (lay-up 45) or by co-bonding using a suitable prepreg system. The precured tabs shall be bonded on both specimen faces with an adhesive system that will me
37、et the temperature and ageing requirements. Care should be taken that the (co-)bonding temperature does not add any undesired post cure effect to the laminate. 7.5 Number of test specimens Five specimens shall be tested per test condition, except when otherwise specified in the applicable technical
38、specification. If tests are carried out after ageing or at a temperature different from room temperature, care should be taken to assure that room temperature/dry reference specimens which have been machined from the same plate as the specimen under investigation are also tested. 7.6 Ageing of speci
39、men ln case of tests after immersion, the conditioning shall be according to EN 2489. ln case of tests after exposure to humid atmosphere, the conditioning shall be according to EN 2823. BS EN 6031:2015EN 6031:2015 (E) 7 8 Procedure 8.1 Conditioning The storage and testing of the as-cured specimens
40、(see EN 2743) shall be carried out at (23 2) C, (50 5) % relative humidity in accordance with EN 2743. Aged specimens shall be tested directly after the ageing procedure (a maximum of 8 h at (23 2) C is allowed). 8.2 Determination of dimensions Measure and record before ageing and mechanical testing
41、 the thickness and width at 3 points in the non-gripping area of the specimen. Use for the thickness the micrometer (see 6.2) and for the width the vernier caliper (see 6.3) or the micrometer (see 6.2). 8.3 Tensile testing Place test specimen into wedge action or hydraulic tension grips of the testi
42、ng machine (see 6.1), in such a way that the tabs are fully clamped; see Figure 2 for details. Alignment of the test specimen in the test machine shall be as accurate as possible, in order to avoid introducing any bending loads. The tensile load shall be applied at a crosshead speed of 1 mm/min unti
43、l 2 % longitudinal strain has been reached; the 0 and 90 strains being recorded versus the load by the strain indicator device (see 6.4) continuously throughout the test. At this point the speed is to be increased to 10 mm/min until failure (if necessary, the strain recording may revert to a longitu
44、dinal record of crosshead movement by constant chart feed only). If strain indicators are used on both sides of the specimen, the strain in each direction is the average of the strain in that direction measured on both sides of the specimen. NOTE It is allowed to arrange the longitudinal and transve
45、rse strain indicators in the wheatstone bridge in such a way that the (0 90) is measured directly (see 9.2). Record the maximum load carried by the specimen during the test and time to failure. 8.4 Elevated and sub-zero temperature tests Apply a thermocouple (see 6.5) on the composite material as cl
46、ose as possible to the centre of the specimen and seal the thermocouple from the surrounding air by using vacuum bag sealant (see 6.6). After a dry specimen has reached a temperature of 2 C below the required elevated temperature or 2 C above the required sub-zero temperature, the specimen shall be
47、maintained at the required condition for 5 min prior to testing. The above time for aged specimen is 1 min. BS EN 6031:2015EN 6031:2015 (E) 8 9 Presentation of the results 9.1 Shear strength (see 3.3) P.Twt= 0,5maxwhere T is the shear strength, in N/mm2; P max. is the highest tensile load during tes
48、ting, in N; w is the average of the three width measurements per specimen, in mm; t is the average of the three thickness measurements per specimen, in mm. 9.2 Shear modulus (see 3.5) PGwt= 0 900,5()where (see Figure 3) G is the shear modulus, in N/mm2; P is the difference in tensile loads at (0)2=
49、2 500 10-6and at (0)1= 500 10-6, in N; w is the average of the three width measurements per specimen, in mm; t is the average of the three thickness measurements per specimen, in mm; 0= (0)2 (0)1= 2 000 10-6; 90is the difference in transverse strains corresponding to (0)2= 2 500 10-6 and (0)1= 500 10-6; (note: 90is negative). NOTE If 0 90is measured directly (see Figure 4) than: P is the difference in tensile loads at (0 90)2= 4 50
