1、- AECMA PREN*bObO 95 m 1012311 0010233 431 m Edition approved for publication 1995-1 2-1 5 AECMA STANDARD NORME AECMA AECMA NORM AIB/TF6 Chairman Mr K. Schneider Comments should be sent within six months after the date of publication to AECMA Gulledelle 94 B-1200 BRUXELLES prEN 6060 Edition PI Decem
2、ber 1995 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 Fibre reinforced plastics Test method Determination of the tensile single lap shear str
3、ength Srie arospatiale Luft- und Raumfahrt Mthode dessai Prfverf ahren Matires plastiques renforces de fibres Dtermination de la contrainte de cisaillement dun joint recouvrement simple Faserverstrkte Kunststoffe Bestimmung der Bindefestigkeit von einschnittig berlappten Klebungen im Zugversuch This
4、 “Aerospace Series“ Prestandard has been 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 commen
5、t by the Member countries. Subsequent to the publication of this Prestandard, the technical content shall not be changed to an extent that interchangeability is affected, ph ysically or functionally, without re-identification of the standard. After examination and signature of the AECMA Standard Che
6、cking Centre INPS) and formal agreement 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. AECMA PRENubObO 95 H L0123Ll 0030234 378 H Page 2 prEN 6060 : 1995 Contents list 1 2 3 4 5 6 7 8
7、 9 10 Scope Normative references Definitions Principle of the method Designation of the method Apparatus Test specimen Procedure Presentation of the results Test report AECMA PREN*bObO 95 I10123111 00110235 204 Page 3 prEN 6060 : 1995 1 Scope This standard specifies the procedure to determine the te
8、nsile single lap shear strength of fiber reinforced composites on different specimen types and laminate configurations, like full depth, co-bonded or secondary bonded laminates. Specimen may either be unsupported or supported during the test. Support retricts the amount of bending during the test le
9、ading to different test results. 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 EN 2374 Aerospace series Glas
10、s fiber reinforced moulding and sandwich composites Production of test panels EN 2489 Aerospace series Fiber reinforced plastics Determination of the action of liquid chemicals EN 2565 EN 2743 EN 2823 Aerospace series Preparation of carbon fiber reinforced resin panels for test purposes ” Aerospace
11、series Reinforced plastics Standard procedures for conditioning prior to testing ) Aerospace series Fiber reinforced plastics Test method for the determination of the effect of exposure to humid atmosphere on physical and mechanical characteristics Parameters for conditioning and testing ) 3 Definit
12、ions 3.1 Full depth specimen Designation: Table 1 3.1.1 Full depth specimen, laminate Laminate of full specimen thickness cured in a one step operation containing only fiber reinforced layers (see figure 1). 3.1.2 Full depth specimen, with adhesive Laminate of full specimen thickness cured in a one
13、step operation containing one adhesive layer in the centre (see figure 2). I Published as AECMA Prestandard at the date of publication of this standard - _ AECMA PREN*bObO 95 LO12311 0030236 140 W Page 4 prEN 6060 : 1995 3.1.2 Full depth specimen, with adhesive Laminate of full specimen thickness cu
14、red in a one step operation containing one adhesive layer in the centre (see figure 2). 3.2 Co-bonded specimen Designation: Table 1 3.2.1 Co-bonded specimen, laminate Laminate of full specimen thickness which has been manufactured in two steps containing only fiber reinforced layers (see figure 1).
15、In the first step a laminate of half the thickness of the specimen is cured. In the second step the other half of the specimen thickness is laminated to the first part and cured, providing also the bonding to the first part. 3.2.2 Co-bonded specimen, with adhesive Laminate of full specimen thickness
16、 which has been manufactured in two steps containing one adhesive layer in the bondline (see figure 2). In the first step a laminate of half the thickness of the specimen is cured. In the second step the other half of the specimen thickness is laminated to the first part including the adhesive layer
17、 and cured. 3.3 Secondary bonded specimen Designation: Table 1 3.3.1 Secondary bonded specimen, laminate Specimen prepared by bonding of two already cured laminates of half specimen thickness each, using suitable fiber reinforced material (see figure 1). 3.3.2 Secondary bonded specimen, adhesive Spe
18、cimen prepared by bonding of two already cured laminates of half specimen thickness each, using suitable adhesive (see figure 2). 3.4 Tensile single lap shear strength Shear strength determined in a tensile test with a single overlapped specimen taken into account the load at rupture and the overlap
19、ping area. 3.5 Nominal thickness Nominal thickness is defined as the thickness a laminate shall achieve taken into account a specific number of layers and the cured ply thickness of the single layer. Cured ply thickness is based on the amount of fiber involved and the optimum fiber content. It can b
20、e calculated taken into account the fiber areal weight, density of fiber and resin and the defined optimum fiber content related to the material involved. Page 5 prEN 6060 : 1995 Description block 4 Principle of the method Identity block A fiber reinforced specimen with single overlap area will be l
21、oaded in a tensile test. Load will be applied continuously to a supported or unsupported specimen until it fails in shear mode in the overlap area. The tensile single lap shear strength will be calculated. Number of this standard Specimen type I (see table 1) Laminate configuration 1 (see table 1) 6
22、 Apparatus 6.1 Tensile testing machine, accurate to within 1 % in the load range used, capable of operating at a crosshead speed of 1 mm/min. 6.2 Vernier calliper accurate to 0,l mm. 6.3 Temperature chamber applied to the testing machine covering the needed test temperatures with an accuracy of f 3
23、O C. 6.4 Temperature measuring equipment accurate to t 0,2% at the applied test temperature ranges. 6.5 Moisture chamber covering the requirement of EN 2743 and EN 2823, if needed. 6.6 Machining equipment able to provide the slots and the cuts in the needed accuracy and quality adopted to the materi
24、als involved to prepare the specimens. 7 Test specimen 7.1 Number of specimens Five specimens shall be tested per test condition, except when otherwise specified in the Technical/Material Specification. AECMA PREN*bObO 95 3032333 0030238 T13 W Page 6 prEN 6060 : 1995 7.2 Preparation 7.2.1 Panels The
25、 panels shall be prepared in accordance with relevant figures as full depth laminates (see 3.1 I, co-bonded (see 3.2) or secondary bonded (see 3.31 panels according to the requirements of EN 2374 and EN 2565 as far as applicable, accuracy in fiber orientation shall be t2,5O. The specification invoki
26、ng the test may ask for different laminate thicknesses and/or lay ups. Pretreatment of cured parts of panels prepared in two step operations shall be done in accordance with 7.2.2, if the specification invoking the test does not give different information. The material selection and the curing param
27、eters shall be provided by the specification invoking the test. Ageing or fluid soaking of panels to be co-bonded (see 3.2) or secondary bonded (see 3.31, followed by a drying and cleaning operation may be specified in the specification invoking the test. 7.2.2 Pretreatment of cured laminates Pretre
28、atment of cured laminates for further bonding operations to prepare the complete panels (see 7.2.1 shall be done as follows: - removal of peel-ply, if any - abrading with alumina Grit paper (grade 2 220) or Scotch Brite type A fine until disappearance of gloss, or, if peel-ply has been used, until e
29、ntire disappearance of surface grid pattern, taking care not to damage any fibers. - cleaning and possible control test (water break test, etc.) according to the specification invoking the test, avoiding cleaning agent drying by evaporation. - maximum open time after pretreatment is 24h, except othe
30、rwise specified in the invoking specification. 7.2.3 Specimen The specimen shall be cut from the laminate panel which have been slotted in accordance with figure 1 or figure 2 as relevant, to create an overlap area for testing. Designation of the individual specimens shall assure reference to the pa
31、nel including position in the panel. Cutting the specimens and especially the slotting shall be done very carefully to achieve usable specimens with minor scatter of results. In cases the slots are above the limits specimen will fail in tension instead of shear at lower results, below the limits the
32、 values obtained may be much to high because residual fibers not cut will determine the rupture. Achieving the radius in the slots will contribute to a low scatter of results. Specimens shall be controlled accordingly by measurements and critical visual examination. AECMA PREN*bObO 95 = 3012333 0030
33、239 95T Page 7 prEN 6060 : 1995 8 Procedure 8.1 Ageing of specimen Tests after exposure to humid atmosphere shall be in accordance with EN 2823. Tests after immersion shall be in accordance with EN 2489. 8.2 Conditioning The storage and the testing of as-cured specimens (see EN 2743) shall be carrie
34、d out at (23 i 2)OC, (50 i 51% relative humidity in accordance with EN 2743. Aged specimen shall be tested directly after the ageing procedure, maximum interval of 8 hours at (23 i 2)OC is allowed. 8.3 Determination of dimensions Before testing the width and the length of the overlap area have to be
35、 determined to the nearest of 0,l mm using the vernier calliper (see 6.3). Specimen thickness shall be measured in the overlap area. For requirements refer to the relevant figure. 8.4 Testing 8.4.1 Attachment of the specimen I test procedures Specimens shall be symmetrically and rigidly placed into
36、the jaws of the testing machine fulfilling the requirements of figure 3 (type A for unsupported specimen and type B for supported specimen). If test procedure B (supported) is invoked by the relevant specification supporting jig in accordance with figure 3 shall be applied. Screws of the supporting
37、jig shall only be tightened by hand to keep the jig in place. The supporting jig shall be mounted in such a way that it can still be moved by hand. 8.4.2 Loading Work scale of the testing machine shall be selected in such a way that the loads obtained throughout the test are comprised within 10% to
38、90% of the scale. The load shall be applied with a constant cross head speed of 1 mm/min until rupture of the specimen. 8.4.3 Elevated and sub-rero temperature tests For specimen tested unsupported a thermocouple shall be applied to the specimen surface in the overlap area and isolated from surround
39、ing air by suitable sealant material, like vacuum bag sealant material (see figure 3). In case of supported testing a thermocouple shall be introduced into one of the slots (see figure 3). AECMA PREN*bObO 95 1012311 0010240 671 Page 8 prEN 6060 : 1995 After a dry specimen has reached a temperature o
40、f 2OC below the required elevated temperature or 2OC above the required sub-zero temperature, the specimen shall be maintained at the obtained condition for 5 minutes prior to testing. The procedure for aged specimen shall be in accordance with EN 2823. 9 Presentation of the results 9.1 Failure mode
41、 Failure mode of each specimen shall be determined. Only specimens which have failed in shear mode in the overlap area shall be taken into consideration for presentation of tensile single lap shear strength results. Specimen failed in tension mode or with residual tension mode (see 7.2.3) shall be e
42、xcluded or investigated. Specification invoking the test may ask for detailed investigation of the surfaces of the shear failures. 9.2 Tensile single lap shear strength Following formula shall be used: P LxW r= where: r P L W is the tensile lap shear strength, in N / mm2 is the maximum load during t
43、he test, in Newton is the overlap length, in millimetres is the overlap width, in millimetres Note : Specimen of the same material and configuration tested supported will to those tested unsupported (see figure 3). Test results shall be comparison with requirements or for further calculations. achie
44、ve different test results checked accordingly before 10 Test report The test report shall refer to this standard and shall at least include the following: 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 Complete identification of the material tested, including at least: material designation, manufacturer /
45、supplier, batch number, roll number, fiber areal weight, filament count, processing details All details about the preparation of panels and specimens, including any applied ageing before cobonding or secondary bonding Dimensions of the specimens Ageing and/or further treatments prior to testing, con
46、ditioning Date of test, facility and identification of individuals performing the test Equipment, method and test parameters used Individual test results, calculations anf failure modes (e.g. adhesive or cohesive) Any incident which may have affected the results and any deviation from this standard
47、- AECMA PREN*bObO 35 1012311 0010241 508 H Page 9 prEN 6060 : 1995 Table 1 : Specimen configurations TvDe Full depth (see 3.1 1 Type I Co-bonded (see 3.2) Type II Secondary bonded see 3.3) Type III Specimen configuration Laminate configuration Full depth, laminate see 3.1 .I 1 Figure 1 Full depth, w
48、ith adhesive (see 3.1.2) Figure 2 Co-bonded, laminate (see 3.2.1 ) Figure 1 Co-bonded, with adhesive (see 3.2.2) Figure 2 Secondary bonded, laminate (see 3.3.2) Figure 1 Secondary bonded, with adhesive (see 3.3.1 Figure 2 Desianation 1.1 1.2 11.1 11.2 111.1 111.2 Page 10 prEN 6060 : 1995 O O Cu- 21
49、90“ f 1“ - 25,O f 0,5 Il- ta Dimensions in mm I. Symmetrical lay-up fuominal Thickness a: N 4,O rnrn unless otherwise specified nominal thickness (see 3.5) related to ta shall be used to calculate the number of layers needed for the diff erent materials Actual thickness (ta) of the laminates involved shall fulfil the requirements of the relevant Material Specification, in case no requirement is provided, the following requirement shall be used : tn f 0,2 rnm. Slot deDth s : 52 - 55% of ta Figure 1 : Tensile single lap shear specimen (without adhesive) Designa
