1、_ AECMA PREN*b033 95 LOL23Ll 0010150 b3T = PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES (AECMA) Gulledelle 94 - 8-1200 BRUXELLES - Tel. (32) 2 775 81 10 - Fax. (32) 2 775 81 11 ICs : Descriptors : ENGLISH VERSION Aerospace series Carbon fibre reinforced plastics Test method Determin
2、ation of interlaminar fracture toughness energy Mode I - GIc AECMA STANDARD prEN 6033 NORME AECMA Edition PI AECMA NORM December 1995 Srie arospatiale Matires plastiques renforces de fibres de carbone Mthode dessai Dtermination de lnergie de tnacit en rupture interlaminaire Mode I - GIc Luft- und Ra
3、umfahrt Kohlenstoffaserverstrkte Kunststoffe Prfverfahren Bestimmung der interlaminaren Energief reisetzungsrate Mode I - Glc Nota - Extra copies can be supplied by B.N.A.E. - Technopolis 54 - 199, rue Jean-Jacques Rousseau - 921 38 ISSY-LES-MOULINEAUX CEDEX This “Aerospace Series“ Prestandard has b
4、een drawn up under the responsibility of AECMA (The European Association of Aerospace Industries). It is published on green paper for the needs of AECMA-Members. It has been technically approved by the experts of the concerned Technical Committee following comment by the Member countries. Subsequent
5、 to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, physically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Checking Centre (NPSI and formal agreemen
6、t of the Official Services of the Member countries it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for formal vote. I Comments should be sent within six months after the date of publication to I Edition approved for publication 1995-1 2-1 5 AECMA Gul
7、ledelle 94 8-1 200 BRUXELLES AiBiTF6 Chairman Mr K. Schneider aecma 1995 AECMA PREN*b033 95 W LOL23LL OOLO15L 57b = Page 2 prEN 6033 : 1995 Contents list 1 2 3 4 5 6 7 8 9 10 Scope Normative references Definitions Principle of the method Designation of the method Apparatus Test specimen Procedure Pr
8、esentation of the results Test report AECMA PREN*b033 95 1012311 0010152 402 = Page 3 prEN 6033 : 1995 1 Scope This standard specifies the procedure to determine the mode I interlaminar fracture toughness energy GI, of carbon fibre composites manufactured from unidirectional tape or woven fabric. Th
9、is 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 This European Standard incorporates by dated or undated referenc
10、e, provisions from other 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
11、 in it by amendment or revision. For undated references, the latest edition of the publication referred to applies. !N 2565 Aerospace Series Preparation of carbon fibre reinforced resin panels for test purposes I EN 2743 Aerospace Series Reinforced Plastics Standard procedures for conditioning and t
12、esting ) EN 6034 Carbon Fibre Reinforced Plastics Determination of interlaminar fracture toughness energy Mode II - Gii,-test ) 3 Definitions 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
13、 crack growth at an interlaminar crack between two plies of a laminate. 3.2 Mode I The mode indicates the method by which the load is applied to .produce the crack. A mode I crack extends as a result of peel forces perpendicular to the crack plane. 3.3 GI, G, is the designation of the interlaminar f
14、racture toughness energy determined by a mode I test procedure. ” Published as AECMA Prestandard at the date of publication of this standard AECMA PREN*b033 95 LOL23LL OOLOL53 34% Page 4 prEN 6033 : 1995 4 Principle of the method The precracked specimen is loaded continuously by peel-forces until a
15、total propagated crack length of approximately 100 mm has been achieved. During the crack propagation the loads and cross head displacement of the test machine will be recorded continuously. The interlaminar fracture toughness energy is calculated from the propagated crack length and the applied ene
16、rgy determined from the load - cross head displacement diagram. 5 Designation of the method The designation of the method used shall be drawn up according to the following example : Identity block EN 6033 I Description block Carbon fibre reinforced plastic materials Determination of interlaminar fra
17、cture toughness energy Mode I - Glc - test Number of this standard 6 Apparatus 6.1 Tensile testing machine, accurate to within 1 %, in the load range used. The misalignment of the grip faces must be less than 0,05 mm at 300 mm separation, increasing by less than 0,l mm per metre at separations above
18、 300 mm. Parallelism between loading heads should be better than 0,4 mm at any position of the cross head. 6.2 As tabs, bent aluminium strips of about 0,5 - 0,7 mm thick or hinged metallic tabs of about 1,0 mm to 1,5 mm thickness shall be used as shown in figure 1. 6.3 A slide caliper with an accura
19、cy to the nearest 0,05 mm 6.4 Release film e.g. PTFE (Polytetrafluorethylene) foil of about (0,02 to 0,031 mm thickness 6.5 Microscope of magnification of 15-25. 7 Test specimen 7.1 Test specimen description The dimensions of the specimens shall be in accordance with figure 1. If fabric is used, the
20、 thickness shall be of the nearest to figure 1. The fibre direction for tape material shall be at 0 to the specimen length and at Oo/900 for fabric material. If the specification invoking the test also asks for GI, - results according to EN 6034 from the same material, it is recommended to use the r
21、emainder of the laminate as a test specimen for GI, - test (see EN 6034 for specimen dimensions). 7.2 Test specimen preparation The test specimens shall be cut from flat laminates which have been processed in accordance with EN 2565. - AECMA PREN*b033 95 = LOL23LL 0010154 285 Page 5 prEN 6033 : 1995
22、 Cure processing parameters as temperature, pressure and time, as well as any detailed and/or specific information regarding the process if any, shall be given in accordance with the relevant specification invoking the test. To introduce the initial crack, a double layer of release film (see 6.4) wi
23、th dimensions according to figure 1 shall be incorporated at the mid-plane of the laminate. Caution : When testing fabric material, the results may be influenced by the positioning of the crack between the layers (nested, unnested etc.). It shall be fixed clearly before Starting manufacturing the sp
24、ecimens, which interlaminar area shall be tested and how to manufacture specimens. The metallic end tabs shall be bonded to the specimen according to figure 1. A high peel strength material shall be used for bonding the tab. The bonding process (surface preparation, curing temperature) may not affec
25、t the properties of the material to be tested. 8 Procedure 8.1 Conditioning Specimens are to be tested dry r in the cured state at room temperature, should first be conditioned at (23 f 2I0C, (50 i 5%) RH in accordance with EN 2743 if not otherwised imposed by the relevant specification invoking the
26、 test. 8.2 Determination of dimensions The average of a minimum of three measurements along the length of the specimen is to be recorded. The width of the specimens shall be measured to the nearest 0,l mm using the slide caliper (see 6.3). 8.3 Testing Align the specimen in the test fixture. To avoid
27、 any influence of the incorporated release film the specimen shall be loaded until an initial crack length of 1 O to 15 mm has been achieved. Mark the position of the initial crack tip after preloading on both sides of the specimen using microscope of 6.5. A thin layer of white ink applied to the lo
28、ngitudinal side faces of the specimen may be used to facilitate this measurement. Load the specimen constantly with a cross head speed of 10 mm/min until a total crack length of about 100 mm has been achieved Record load and cross head displacement during the test Mark the final crack length on both
29、 sides of the specimen using the microscope of 6.5 Unload the specimen Determine the propagated crack length (see 9) Analyse the results in accordance with 9 9 Presentation of the results To calculate the interlaminar fracture toughness energy, the following formula shall be used : Page 6 prEN 6033
30、: 1995 axw where : GI, A a W is the fracture toughness energy, in J/m2 is the energy to achieve the total propagated crack length, in Joules (Integration of the area of the load-cross head displacement diagram according to figure 2) is the propagated crack length, in millimetres (Final crack length
31、minus inital crack length) is the width of the specimen, in millimetres 10 Test report The test report shall refer to this standard and include the following : 1 O. 1 Complete identification of the tested material, including manufacturers name, designation, batc number etc. 10.2 All details about th
32、e preparation of specimens 10.3 The measured specimen dimensions 10.4 Ageing and/or exposure conditions prior to the test 10.5 Date of test, facility and indentification of individuals performing the tests 10.6 Equipment, method and test parameters used. 10.7 Individual test results and calculations
33、 plus a set of typical load-cross head displacernent curves. Individual curves shall be kept in file by the test laboratory. 10.8 Any incident which may have effected the results and any deviation from this standard. Fibre bridgeing in the crack or movement of the crack to plies adjacent to the mid
34、plies shall be reported. - AECMA PRENrb033 95 m 1012311 0010156 058 m Page 7 prEN 6033 : 1995 mm L = (250 I 5) mrn II = (25 * 1) mm W = (25.0 r 0.21 mm t = (3.0 I 0.2) mm Figure 1 : Test specimen - - AECMA PRENJb033 95 9 1012311 0010157 T94 Page 8 prEN 6033 : 1995 t z -0 m O cross head displacement (ml - D1 : cross head displacement at initial crack length (see 8) D2 : cross head displacement at final crack length (see 8) A : calculated energy (see 81 Figure 2 : Load-Cross head displacement diagram
