BS EN 6034-2015 Aerospace series Carbon fibre reinforced plastics Test method Determination of interlaminar fracture toughness energy Mode II GIIC《航空航天系列 碳纤维增强塑料 试验方法 层间断裂韧度能量的测定 模.pdf

1、BSI Standards PublicationBS EN 6034:2015Aerospace series Carbonfibre reinforced plastics Test method Determinationof interlaminar fracturetoughness energy Mode II GIICBS EN 6034:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 6034:2015.Users attention is dr

2、awn to subclause 7.1, which requires that theinitial crack in the test specimen be introduced in a defined ModeI procedure (outlined in EN 6033 Aerospace series Carbon fibrereinforced plastics Test method Determination of interlaminarfracture toughness energy Mode I GIC), in order to achievereproduc

3、ible test results.A crack produced in Mode I is a result of peel forces perpendicularto the crack plane; a crack produced in Mode II is a result of shearforces at the crack tip introduced by a flexural test (specified in EN6034). However, the possibility of failure outlined in EN 6033 rarelyoccurs.

4、The UK committee notes that in practice test results havebeen achieved by initiating the crack in Mode II, rather than usingtested specimens from EN 6033.The UK participation in its preparation was entrusted to TechnicalCommittee ACE/65, Non-metallic materials for aerospace purposes.A list of organi

5、zations 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 responsible for its correctapplication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISB

6、N 978 0 580 82986 4ICS 49.025.40Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 November 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e

7、 c t e dBS EN 6034:2015EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 6034 November 2015 ICS 49.025.40 English Version Aerospace series - Carbon fibre reinforced plastics - Test method - Determination of interlaminar fracture toughness energy - Mode II - GIIC Srie arospatiale - Matires plastiq

8、ues renforces de fibres de carbone - Mthode dessai - Dtermination de lnergie de tnacit en rupture interlaminaire - Mode II - GIIC Luft- und Raumfahrt - Kohlenstofffaserverstrkte Kunststoffe - Prfverfahren - Bestimmung der interlaminaren Energiefreisetzungsrate - Mode II - GIICThis European Standard

9、was approved by CEN on 10 August 2013. 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

10、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 CEN member into its own l

11、anguage 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 Macedonia, France, Germany, Gre

12、ece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG

13、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 6034:2015 EBS EN 6034:2015EN 6034:2015 (E) 2 Contents Page European foreword . 3 1 Scope 4 2 Normative references

14、 4 3 Terms and definitions . 4 4 Principle of the method 5 5 Designation of the method . 5 6 Apparatus . 5 7 Test specimen . 5 8 Procedure. 6 9 Presentation of the results 8 10 Test report . 8 BS EN 6034:2015EN 6034:2015 (E) 3 European foreword This document (EN 6034:2015) has been prepared by the A

15、erospace 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 member countries of ASD, p

16、rior 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. Attention is drawn to th

17、e 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 organizations of the following count

18、ries 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, Norway, Pol

19、and, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 6034:2015EN 6034:2015 (E) 4 1 Scope This standard specifies the procedure to determine the mode II interlaminar fracture toughness energy GIICof carbon fibre composites manufactured from unid

20、irectional tape or woven fabric. This standard does not give any directions necessary to meet 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 w

21、hole 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 2565, Aerospace series Preparatio

22、n of carbon fibre reinforced resin panels for test purposes 1)EN 2743, Aerospace series Fibre reinforced plastics Standard procedures for conditioning prior to testing unaged materials EN 2823, Aerospace series Fibre reinforced plastics Test method for the determination of the effect of exposure to

23、humid atmosphere on physical and mechanical characteristics 1)EN 6033, Aerospace series Carbon fibre reinforced plastics Test method Determination of interlaminar fracture toughness energy Mode I GIC1)3 Terms and definitions For the purposes of this document, the following terms and definitions appl

24、y. 3.1 interlaminar fracture toughness energy the interlaminar fracture toughness energy is the energy per unit plate width which is necessary to produce an unit crack growth at an interlaminar crack between two plies of a laminate 3.2 mode II the mode indicates the method by which the load is appli

25、ed to produce the crack. Mode Il crack extends as a result of shear forces at the crack tip introduced by a flexural test 3.3 GIICGIICis the designation of the interlaminar fracture toughness energy determined by a mode II test procedure 1) Published as ASD-STAN Prestandard at the date of publicatio

26、n of this standard. http:/www.asd-stan.org/ BS EN 6034:2015EN 6034:2015 (E) 5 4 Principle of the method The end notched flexure specimen is used for mode Il testing. A precracked specimen is loaded in a three point bend fixture (see Figure 2) until crack propagation onset. The load applied to the sp

27、ecimen and the cross head displacement of the test machine are recorded continuously during the test. The total fracture toughness energy is calculated from the initial crack length and load-displacement diagram. 5 Designation of the method The designation of the method used shall be drawn up accord

28、ing to the following example: Description block Carbon fibre reinforced plastic materials Determination of interlaminar fracture toughness energy Mode II GIIC- test Identity block EN6034 Number of this standard NOTE If necessary, the code I9005 may be placed between the description block and the ide

29、ntity block. 6 Apparatus 6.1 Test machine accurate to within 1 % in the load range used. 6.2 Device for recording the deflection as a function of load accurate to within 1 % in the deflection range used. 6.3 Vernier caliper accurate to the nearest 0,1 mm. 6.4 Flat face micrometer accurate to the nea

30、rest 0,01 mm. 6.5 Microscope of a magnification of 15-25. 7 Test specimen 7.1 Test specimen description To achieve reproducible test results the GIIC-test shall only be performed with specimens (see Figure 1) where the initial crack has been introduced in a defined mode I procedure (see EN 6033). Th

31、e test specimen shall be cut from the residual part of GICspecimen tested or at least loaded and cracked per EN 6033, and fulfilling the following requirements. BS EN 6034:2015EN 6034:2015 (E) 6 7.2 Test specimen preparation Prepare the required laminates according to EN 2565 method B for carbon. Th

32、e crack front remains approximately a straightline perpendicular to the longitudinal direction of the specimen (as presumed by the marks performed on both already painted longitudinal side faces of the specimen to locate the crack tips after crack stabilization under the mode I loading). The uncrack

33、ed portion of the specimen is of sufficient length to comply with the requirements of Figure 1. The observation during the mode I loading did not show neither fibre bridgings nor moving of the crack to plies adjacent to the mid plies. The specimen shall be cut in a way that the specified remaining c

34、rack length of Figure 1 is guaranteed. Specimens longer than 112 mm can be used to realize a serie of tests for the determination of GIICif needed. Appropriate identification shall be maintained throughout the specimen preparation to ensure traceability to the GICspecimen and to the original laminat

35、e. If not otherwise defined by the specification invoking the test, three specimens shall be tested per test condition. CAUTION When testing fabric material, the results may be influenced by the position of the crack between the layers (nested, unnested etc.). It shall be clearly stated which interl

36、aminar area shall be tested and how to manufacture the specimens. 8 Procedure 8.1 Conditioning If not otherwise defined by the specification invoking the test, specimens to be tested dry or in the as cured state, should first be conditioned at (23 2) C, (50 5) % RH in accordance with EN 2743, same r

37、equirements to be applied to perform room temperature testing. Aged specimens shall be tested directly after ageing procedure (a maximum storage of 8 h at (23 2) C is allowed before testing). 8.2 Determination of dimensions The width and length of the specimens shall be measured using a vernier cali

38、per (see 6.3). A minimum of three thickness measurements distributed over the specimen shall be made using a flat face micrometer (see 6.4), the average shall be recorded. 8.3 Testing The crack length has to be measured by vernier caliper (see 6.3), using the microscope (see 6.5). A thin layer of wh

39、ite ink applied to the longitudinal side faces of the specimen may be used to facilitate this measurement. For the entire duration of the test, a continuous load-displacement record shall be made, measuring the displacement of the loading nose. BS EN 6034:2015EN 6034:2015 (E) 7 Place the specimen in

40、 the test fixture in accordance with Figure 2, assuring the position of the initial crack: a = (35 1) mm The following procedure shall then apply: Adjust the load cell reading at zero. Remove any slack between the loading nose and the specimen by making the needed displacement. Adjust the displaceme

41、nt reading at zero if necessary. Load the specimen under displacement control at a displacement rate of 1 mm/min. Optically observe the crack tip in order to detect the crack propagation onset (microscope of 6.5). Record the critical load at delamination crack onset and stop the loading as soon as e

42、vidence of crack propagation has been confirmed by a small load drop. 8.4 Elevated and sub-zero temperature tests If not otherwise defined by the specification invoking the test, apply a thermocouple on the specimen as close as possible to cracked area of the specimen and seal the thermocouple from

43、the surrounding air by using vacuum bag sealant. The soak time at test temperature, defined by the specification invoking the test, shall be (5 0,5) min for dry specimens and in accordance with EN 2823 for conditioned specimen. If more then one determination is provided for, wait for crack stabiliza

44、tion under load and mark the current tip location on the painted sides of the specimen. Unload the specimen to zero. The complete procedure shall be repeated for the subsequent determinations when needed. Unless otherwise specified, the remaining uncracked portion of the specimen shall be delaminate

45、d after removal from the test fixture (cooling the specimen down to liquid nitrogen temperature will facilitate this operation). Verification measurements of the crack lengths shall then be made from the crack front (thumbnail marks) on the fractured specimen. Care shall be taken to protect the dela

46、mination surfaces for later inspection of failure mode if requested. The results shall be analysed in accordance with Clause 9. BS EN 6034:2015EN 6034:2015 (E) 8 9 Presentation of the results 9.1 Calculation To calculate GIICthe following formula shall be used: Pa dwLa +=2IIC339 1000G2 (1/ 4 3 )wher

47、e GIICis the fracture toughness energy, in J/m2; d is the crosshead displacement at crack delamination onset, in mm; P is the critical load to start the crack, in N; a is the initial crack length (see Figure 2), in mm; w is the width of the specimen, in mm; L is the span length (see Figure 2), in mm

48、. 9.2 Test results validation The test results and calculation shall be valid if the crack front is approximately perpendicular to the specimen longitudinal direction and does not extensively change from a straightline across the width of the fractured test specimen. 10 Test report The test report s

49、hall refer to this standard and include the following: 10.1 Complete identification of the tested material, including manufacturers name, designation, batch number, etc. 10.2 All details about the preparation of specimens. 10.3 Measured dimensions of the specimens. 10.4 Ageing and/or exposure conditions prior to the test. 10.5 Date of test, facility and identification of individuals performing the test. 10.6 Equipment, method and test parameters used. 10.7 Individual test results and calculations