1、AECMA PRENlkb035 95 LOL2311 O009993 5TT = Edition approved for publication AECMA STANDARD NORME AECMA AECMA NORM AIBITFG Chairman Comments should be sent within six months after the date of publication to prEN 6035 Edition PI November 1995 - PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTR
2、IES (AECMA) Gulledelle 94 - 8-1200 BRUXELLES - Tel. (32) 2 775 81 10 - Fax. (32) 2 775 81 11 ICs : Descriptors : ENGLISH VERSION Aerospace series Fibre reinforced plastics Test method Determination of notched and unnotched tensile strength Srie arospatiale Matires plastiques renforces de fibres Mtho
3、de dessai Dtermination de la rsistance en traction lisse et en traction troue Luft- und Raumfahrt Faserverstrkte Kunststoffe Prfverfahren Bestimmung der Kerbzugfestigkeit an gekerbten und ungekerbten Probekrpern This “Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA
4、(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 to the publication of this Prestandard, the te
5、chnical 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 agreement of the Officiai Services of the Member countr
6、ies it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for formal vote. 1995-1 1-30 AECMA Gulledelle 94 6-1 200 BRUXELLES Mr K. Schneider I aecma 1995 - AECMA PREN*b035 95 = LOL23LL O009994 436 Page 2 prEN 6035 : 1995 Contents list 1 2 3 4 5 6 7 8 9 10
7、Scope Normative references Definitions Principie of the method Designation of the method Apparatus Test specimen Procedure Presentation of the results Test report AECMA PRENxb035 75 m LOL23LL 0009995 372 Page 3 prEN 6035 : 1995 1 Scope This standard defines a method to be used to determine the tensi
8、le strength of notched and unnotched fibre reinforced plastics. It is applicable to composite laminates with unidirectional plies or woven fabrics reinforcement. This standard does not give any direction necessary to meet health and safety requirements. It is the responsibility of the user of this s
9、tandard to consult and establish appropriate health and safety precautions. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications ar
10、e 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 revision. For undated references, the latest edition of the publication referred to applies. EN 2374 Aerospace ser
11、ies Glass fibre reinforced mouldings and sandwich Production of test panels EN 2489 EN 2565 EN 2743 EN 2823 Aerospace series Fibre reinforced plastics Determination of the action of liquid chemicals 1) Aerospace series Preparation of carbon fibre reinforced resin panels for test purpose 1) Aerospace
12、 series Fibre reinforced plastics Standard atmospheres for conditioning and testing Aerospace series Fibre reinforced plastics Test method for the determination of the effect of exposure to humid atmosphere on physical and mechanical characteristics ?I 3 Definitions 3.1 Unnotched tensile strength Ma
13、ximum tensile load experienced by the unnotched test specimen divided by the initial cross sectional area within the gauge length. 3.2 Notched tensile strength Maximum tensile load experienced by the notched test specimen divided by the initial gross cross sectional area within the gauge length. 1)
14、Published as AECMA Prestandard at the date of publication of this standard. AECMA PRENab035 95 = LOL23Ll OOOb 209 Page 4 prEN 6035 : 1995 3.3 KT value Unnotched tensile strength divided by the notched tensile strength. 4 Principle of the method A tensile test on unnotched specimen is carried out in
15、order to determine the original material strength. A test is performed on notched specimen to determine the residual strength. 5 Designation of the method The designation of the method shall be in accordance with the following example. Description block Identity block Determination of notched and un
16、notched Fibre reinforced plastics tensile strength Number of this standard Laminate configuration A (see table 1) 6 Apparatus 6.1 Calibrated tensile test machine accurate to within loh, equipped with facilities to record maximum load. 6.2 Chamber adapted to the machine to carry out tests at temperat
17、ure. The temperature shall be maintained within f 3C. 6.3 Timer. 6.4 6.5 Thermocouple with recorder to monitor temperature for tests at other than ambient. Flat faced micrometer with 6 mm diameter faces, accurate to 0,Ol mm 6.6 Vernier calliper accurate to the nearest 0,l mm. 7 Test specimen 7.1 Spe
18、cimen description For the description, dimensions and tolerances see figure 1 for notched type specimen and figure 2 for unnotched type specimen. The laminate configurations for the fibre directions are defined in table 1. 7.2 Test specimen preparation The specimens are cut out from laminates. The c
19、oefficient of variation in the thickness measurements shall be smaller than 2% per laminate. The laminates shall be produced according to EN 2565 for carbon and EN 2374 for glass. Special precautions have to be taken to ensure that no delamination occurs during machining especially for the drilling
20、of the notched specimens. The laminate should be inspected for example by C-Scan to establish that the laminate is worth testing. If the NDT reveals unacceptable defects,limits defined in the specification invoking the test, the laminate should not be tested. The process parameters shall be in line
21、with the specification invoking the test. AECMA PREN*b035 95 LOL231L O009997 I45 D Page 5 prEN 6035 : 1995 7.3 Tabs The tests may be performed without the specimen being tabbed. However, if tabs are used they shall be strain compatible with the composite being tested either, by using precured tabs o
22、f two plies of fabric, lay-up + and - 45“, or by co-bonding using a suitable prepreg system. The precured tabs shall be bonded on both specimens faces with a suitable adhesive system. Care should be taken that the adhesive bonding temperature does not add any undesired post cure effect to the lamina
23、te. 7.4 Number of specimens Five specimens shall be tested per test condition, except when otherwise specified in the technical specif ication. 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 referenc
24、e specimens, which had been machined from the same plate as the specimens under investigation are also tested. 7.5 Ageing In case of tests after immersion, the conditions shall be according to EN 2489. For tests after exposure to humid atmosphere, the conditioning shall be in accordance with EN 2823
25、. 8 Procedure 8.1 Conditioning The storage and testing of as received specimens shall be carried out at (23 k 2) OC, (50 f 5) Yo relative humidity in accordance with EN 2743. Aged specimens shall be tested within a maximum of 8 hours after removal from the exposure environment. 8.2 Determination of
26、dimensions Measure and record the thickness and width at three points in the gauge length of the specimen before ageing and again before mechanical testing. Use the micrometer (see 6.5) for the thickness and the vernier calliper (see 6.6) for the width. Average the three measurements. 8.3 Test at am
27、bient temperature Place the specimen in the jaws, ensuring that it is aligned within 1“ and centred on the machine axis. (Note: The jaws shall fully cover the tabs if used). Select the load range such that failure occurs between 20 o/o and 80 % of full scale. Tensile load shall be applied at a const
28、ant cross head speed of 2 mmmin. Record the maximum load Pr 8.4 Test at temperature other than ambient Apply a thermocouple (see6.4) on the composite material as close as possible to the centre of the specimen and seal the thermocouple from the surrounding air by using vacuum bag sealant. After a dr
29、y specimen has reached a ternpararture of 2C below the required elevated temperature or 2C above the required sub-zero temperature, the specimen shall be maintained at the required condition for five minutes prior to testing. The above time for aged specimen is 1 minute The heat up/soak cycle used s
30、hall be given in the test report. For specimens that have been subjected to fluid immersion, apply EN 2489. For specimens that have undergone humidity ageing, apply EN 2823. Follow the same procedure as for the test at ambient temperature. AECIA PRENmb035 95 W LOL23LL 0009998 081 Page 6 prEN 6035 :
31、1995 9 Presentation of the results 9.1 Tensile strength ot For notched specimens Pr otn = For unnotched specimens otu = txw Pr where : otn, otu are the tensile strengths for, notched and unnotched specimens, in MPa is the maximum load, in Newton is the specimen width, in millimetres is the thickness
32、 of the specimen, in millimetres Pr W t 9.2 Nominal tensile strength ont For notched specimens For unnotched specimens ontu = where Pr tnxw Pr tn x w ontn ontu Pr W is the specimen width, in millimetres tn are the nominal tensile strength for, notched and unnotchedspecimens, in MPa is the maximum lo
33、ad, in Newton is the nominal thickness of the specimen, in millimetres, as specified in the relevant material specification 9.3 KT value (see 3.3) AECMA PREN*b035 95 m LOL23LL 0009999 TLB m Tapes Page 7 prEN 6035 : 1995 Fibre mass per unit area Quasi-isotropic laminates Directed laminates (!Ym2 1 Ty
34、pe A Type B 130 -145 160 -190 260 -290 ( 45, O, -45,90 ) 4 sym ( 45, O , -45,90 ) 3 sym ( 45, O, -45,90 ) 2 sym ( O ,45 , -45, O ,90 ) 3 sym ( O ,45 , -45 , O ,90 ) 2 sym ( O ,45, -45, O ,90 ) 2 sym 10 Test report The test report shall refer to this standard and shall include the following. 10.1 10.
35、2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 Complete identification of the material tested, including at least type, source, manufacturers code number, fibre areal weight, filament count, processing details. All details regarding specimen preparation (including when applicable : tabs material, tabs adhesiv
36、e and curing condition of this adhesive) The measured specimen dimensions. Ageing and/or exposure conditions prior to the test. Date of test, facility and identification of individuals performing the test. Equipment, method and test parameters used. Individual values, mean value and standard deviati
37、on of tensile strength for notched and unnotched specimen. KT value Any incident which may have affected the results and any deviation from this standard. di Table 1 : Laminate configurations Lay-ups for different fibre mass per unit area Directed and quasi-isotropic laminates 1) 2) O“ is equivalent
38、 to warp direction and 90“ is equivalent to weft direction n to be determined to have a laminate thickness as close as possible to 4 mm AECMA PRENmb035 95 L0123iIiI OOiIOOOO 123 Page 8 prEN 6035 : 1995 I I - 180 0,5 - Dimensions in rnm L=21 +180mm 1 = tab length : Function of the equipment (test mac
39、hine, jaws, etc) and / or the material to be t : according to lay-up (see table 1) tested (tabs must be able to transfer the shear loads). Figure 1 : Notched tensile specimen R = 200 f 1 /- Il 0,05 f 7 * f I Dimensions in mm L=21 +180mm 1 = tab length : Function of the equipment (test machine, jaws,
40、 etc) and / or the material to be t : according to lay-up (see table 1) tested (tabs must be able to transfer the shear loads). Figure 2 : Unnotched tensile specimen Note: Parallelism of tab faces must be maintained to within 0,05 mrn across width and length. Tabs faces must be parallel with specimen faces to within 0,05mm.
