BS-EN-2243-6-2005.pdf

BRITISH STANDARD AEROSPACE SERIES BS EN 2243-6:2005 Non-metallic materials Structural adhesives Test method Part 6: Determination of shear stress and shear strain The European Standard EN 2243-6:2005 has the status of a British Standard ICS 49.025.50 ? Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 2243-6:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 18 November 2005 © BSI 18 November 2005 ISBN 0 580 46844 5 National foreword This British Standard is the official English language version of EN 2243-6:2005. The UK participation in its preparation was entrusted by Technical Committee ACE/65, Non-metallic materials for aerospace purposes (excluding textiles), to Subcommittee ACE/65/-/63, Structural adhesives, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 15 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 2243-6 October 2005 ICS 49.025.50 English Version Aerospace series - Non-metallic materials - Structural adhesives - Test method - Part 6: Determination of shear stress and shear strain Série aérospatiale - Matériaux non-métalliques - Système d'adhésifs structuraux - Méthodes d'essai - Partie 6 : Détermination de la contrainte et de la déformation de cisaillement Luft- und Raumfahrt - Nichtmetallische Werkstoffe - Strukturelle Klebstoffsysteme - Prüfverfahren - Teil 6: Bestimmung der Schubspannung und Gleitung This European Standard was approved by CEN on 26 September 2005. 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 national standards may be obtained on application to the Central Secretariat 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 language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels © 2005 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 2243-6:2005: E Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 2243-6:2005 2 Contents Page Foreword 3 Introduction. .4 1 Scope . 4 2 Normative references .4 3 Definitions, symbols and abbreviations. .4 4 Health and safety . .5 5 Principle/Technique 5 6 Resources 5 7 Test samples/Test pieces. 6 8 Testing procedure .7 9 Expression of results 8 10 Designation .9 11 Test report .10 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EN 2243-6:2005 3 Foreword This European Standard (EN 2243-6:2005) has been prepared by the European Association of Aerospace Manufacturers - Standardization (AECMA-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 AECMA, 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 April 2006, and conflicting national standards shall be withdrawn at the latest by April 2006. 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 organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 4 Introduction This standard is part of the series of EN non-metallic material standards for aerospace applications. The general organization of this series is described in EN 4385. This standard is a level 3 document as defined in EN 4385. 1 Scope This standard defines the general requirements for the determination of shear stress and shear strain behaviour of structural adhesives by testing in tension metal to metal lap joints, at ambient or other temperatures. This method can also be used to investigate the influence of environmental exposures on structural adhesives. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the force-measuring system (ISO 7500-1:2004). EN 2243-1, Structural adhesives Test methods Part 1 Single lap shear Aerospace series.1) EN 2334, Aerospace series Chromic-sulphuric acid pickle of aluminium and aluminium alloys. EN 2419, Aerospace series Aluminium alloy AL-P2024- T351 Plate 6 mm a 80 mm.2) EN 4385, Aerospace series Non-metallic materials General organisation of standardisation Links between types of standards.2) 3 Definitions, symbols and abbreviations 3.1 Definitions Not applicable 3.2 Symbols and abbreviations For the purposes of this document, the following symbols and abbreviations apply. 1) Published as AECMA Standard at the date of publication of this standard. 2) Published as AECMA Prestandard at the date of publication of this standard. EN 2243-6:2005 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 5 average shear stress (in megapascals); angle of measured shear strain (in radians); d shear displacement (in millimetres); t adhesive thickness (in millimetres); F load (in newtons); L length of overlap (in millimetres); W width of overlap (in millimetres); Ge elastic shear modulus (in newtons per square millimetres). 4 Health and safety This standard does not necessarily include all health and safety requirements, associated with its use. Persons using this standard shall be familiar with normal laboratory/test house practices. It is the responsibility of the user to establish satisfactory health and safety practices and to ensure conformity with any European, national or local laws/regulations. 5 Principle/Technique Not applicable 6 Resources 6.1 Apparatus All test equipment shall be calibrated at intervals not exceeding 12 months. 6.1.1 Tensile testing machine The tensile testing machine shall conform to class 1 of EN ISO 7500-1. The failing load of the test specimen shall be within 20 % and 80 % of the upper limit of the selected loading range of the machine. 6.1.2 Suspension In order to obtain moment-free load application, a Cardanic suspension is required (see Figure 1). 6.1.3 Extensometers They shall meet the following requirements: accuracy of test piece displacement measurement to within 0,001 mm; measurement of test piece overlap displacement (example of three point measurement is shown in Figures 1 and 2); EN 2243-6:2005 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 6 continuous recording of the load-displacement curve; negligible influence of test piece deformation on test results. To eliminate the effect of a non-uniform adhesive layer, it is recommended to measure the overlap displacement on both sides of the test piece (see note). NOTE A correct determination of adhesive characteristics is only possible when properly measuring the adhesive layer shear deformation. Depending on the type of extensometer and its fixing to the test specimen, however, the measured value can include adherent deformations. This should be kept to a minimum. Otherwise, it is necessary to determine with the extensometer used on a dummy specimen (without adhesive layer) the adherent deformation corresponding to the test conditions in order to take it into account in the calculation. 6.1.4 Recorder It shall record continuously the displacement (see 9.2) relative to the load applied throughout the test until failure occurs. 6.2 Materials/Reagents Not applicable 6.3 Qualification of personnel Not applicable 7 Test samples/Test pieces 7.1 Materials 7.1.1 For test temperatures up to 150 °C Aluminium alloy EN 2419 7.1.2 For test temperatures above 150 °C See EN 2243-1. 7.2 Surface preparation before bonding EN 2334 unless otherwise specified 7.3 Bonding The application and curing of the adhesive system (adhesive and primer) shall be carried out according to the material standard unless otherwise agreed with the adhesive system manufacturer. Shims can be applied outside the overlap to adjust the adhesive thickness (see Figures 2 and 3). Adhesive shall not be applied at the location of the shims. The entire mating surface of the two panels shall be bonded. 7.4 Dimensions of panels See Figure 3. EN 2243-6:2005 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 7 7.5 Storage of test panels after bonding They shall be stored under the following conditions: temperature : (23 ± 2) °C; relative humidity : (50 ± 5) %. 7.6 Cutting of panels and preparation of test pieces The panels shall be cut into test pieces (see Figures 2 and 3). The panels made with high temperature curing adhesives shall be cut only after a storage period of 16 hours (see note 1). NOTE 1 For batch acceptance testing, this 16 hours period can be omitted. Nevertheless, for temperature curing adhesive, care shall be taken to cut panels only when their temperature is down to ambient. Perform the cutting operation so as to avoid overheating ( 50 °C) or mechanical damage to the joint (see note 2). NOTE 2 A fine-tooth, circular or band-saw has been found suitable for this purpose. The panels may also be pre-cut outside the area to be bonded. Cutting shall be straight and parallel. After cutting, the test pieces shall be reworked to the required width by milling and the holes shall be drilled (see Figure 2). The use of cooling liquids is not permitted, unless otherwise specified. 7.7 Test pieces 7.7.1 Dimensions See Figure 2. 7.7.2 Number of specimens See material standard. 7.7.3 Identification Each test piece shall be marked to identify the panel from which it was cut and its position in the panel. 8 Testing procedure 8.1 Dimensions measurement Measure the dimensions “L“ and “W“ (see Figure 2) with an accuracy of ± 0,1 mm. Measure the thickness of the adhesive in the middle of the overlap at both sides of the test piece with an accuracy of ± 0,01 mm. The average thickness shall be determined. EN 2243-6:2005 Licensed Copy: sheffieldun sheffieldun, na, Fri Nov 03 01:30:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 8 8.2 Fixing See Figure 1. Install the extensometer(s) on the test piece. The measurement axis shall be aligned parallel to the specimen axis. The ends of the test piece shall be attached by means of pins. The suspension and the test piece shall be aligned such that the long axis of the test piece coincides with the direction of applied tensile force through the fixing points. 8.3 Test temperatures When the test temperature is different from ambient (23 ± 2) °C, then the chamber including suspension shall be stabilized within the test temperature tolerance for at least 30 minutes prior to inserting the test piece. The temperature control of the test piece shall be carried out using a thermocouple. The junction of the thermocouple shall be firmly attached to the test piece in immediate contact with the metal. It shall be shielded from direct heating. 8.4 Loading For test temperature different from ambient, and unless otherwise specified, a minimum exposure time of 10 minutes at the required temperature shall be applied prior to loading. The load shall be applied at a uniform jaws separation of 1 mm/min (see note 1). NOTE 1 For test other than qualification, it can be tolerated to apply the load at speed between 1 mm/min and 2,5 mm/min, or at rate between 4 000 N/min and 5 000 N/min. Record the load-displacement curve (see note 2). NOTE 2 For non-ambient temperature tests, there is a requirement for the test portion of the specimen to be within the specified temperature tolerance throughout the period of loading to failure. The exposure time of ten minutes is normally sufficient to fulfill this requirement. Nevertheless, the test laboratory may be required to prove the heat dwell concept (pr