1、AECMA STANDARD NORME AECMA AECMA NORM Edition approved for publication prEN 4243 Edition P 1 August 2001 Comments should be sent within six months after the date of Dublication to Material Domain PUBLISHED BY THE EUROPEAN ASSOCIATION OF AEROSPACE INDUSTRIES - STANDARDIZATION (AECMA-STAN) Guiledelie
2、94 - 8-1200 BRUXELLES - Tel. (+32) 2 775 81 10 - Fax. (+32) 2 775 81 I1 ICs: Descriptors: Srie arospatiale Feuilles dacrylique Spcification technique ENGLISH VERSION Aerospace series Cast acrylic sheets Technical specification Luft- und Raumfahrt Platten aus Acrylglas Technische Lieferbedingungen Th
3、is %Aerospace Series“ Prestandard has been drawn up under the responsibility of AECMA-STAN (The European Association of Aerospace Industries - Standardization). It is published on green paper for the needs of the European Aerospace Industry. It has been technically approved by the experts of the con
4、cerned Domain following member comments, Subsequent 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 review by users and fo
5、rmal agreement of AECMA-STAN it will be submitted as a draft European Standard to CEN (European Committee for Standardization) for formal vote. 2001-08-31 AECMA-STAN Gulledelle 94 Mr Pays 8-1200 BRUXELLES 0 aecma 20C Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided
6、by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-1 Page 2 prEN 4243: 2001 Blank page Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or net
7、working permitted without license from IHS-,-,-Page 3 prEN 4243: 2001 1 Scope This standard specifies the inspection for cast acrylic sheets (blocks) used for aerospace glazing applications. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from oth
8、er 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 in it by amendment or
9、 revision. For undated references the latest edition of the publication referred to applies. IS0 62 IS0 75 (ait parts) IS0 179 IS0 306 IS0 489 Plastics - Determination of the refractive index IS0 527-2 Plastics - Determination of tensile properties - Part 2: Test conditions for moulding and extrusio
10、n plastics IS0 554 Standard atmospheres for conditioning and/or testing - Specifications IS0 I1 83 (all parts) Plastics - Methods for determining the density of non-cellular plastics Plastics - Determination of water absorption Plastics - Determination of temperature of deflection under load Plastic
11、s - Determination of Charpy impact strength Plastics - Thermoplastic materials - Determination of Vicat softening temperature IS0 2818 IS0 8402 EN 2000 EN 2155-4 EN 2155-5 EN 2155-6 EN 2155-7 EN 2155-8 EN 2155-9 EN 21 55-1 2 EN 21 55-1 9 EN 21 55-20 EN 2155-21 EN 21 55-22 Plastics - Preparation of t
12、est specimens by machining Quality management and quality assurance - Vocabulary Aerospace series - Quality assurance - EN aerospace products - Approval of the quality system of manufacturers Aerospace series - Test methods for transparent materials for aircraft glazing - Part 4: Determination of ul
13、traviolet light transmission over the wavelength range 280 nm to 360 nm 1) Aerospace series - Test methods for transparent materials for aircraft glazing - Part 5: Determination of visible light transmission Aerospace series - Test methods for transparent materials for aircraft glazing - Part 6: Det
14、ermination of optical defects 1) Aerospace series - Test methods for transparent materials for aircraft glazing - Part 7: Determination of optical deviation Aerospace series - Test methods for transparent materials for aircraft glazing - Part 8: Determination of optical distortion Aerospace series -
15、 Test methods for transparent materials for aircraft glazing - Part 9: Determination of haze Aerospace series - Test methods for transparent materials for aircraft glazing - Part 12: Determination of linear thermal expansion Aerospace series - Test methods for transparent materials for aircraft glaz
16、ing - Part 19: Determination of craze resistance Aerospace series - Test methods for transparent materials for aircraft glazing - Part 20: Determination of retention of strength after crazing for as-cast acrylics 1) Aerospace series - Test methods for transparent materials for aircraft glazing - Par
17、t 21: Determination of resistance to crack propagation (K factor) Aerospace series - Test methods for transparent materials for aircraft glazing - Part 22: Determination of thermal relaxation of stretched acrylic sheet 1) Copyright Association Europeene des Constructeurs de Materiel Aerospatial Prov
18、ided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page 4 prEN 4243: 2001 EN 3042 EN 3844-2 EN 4367 ASTM-D 1925 Standard Test Method for Yellowness Index for Plastics (Discontinued 1995, no Aerospace series - Quality assurance - EN
19、aerospace products - Qualification procedure Aerospace series - Flammability of non-metallic materials - Part 2: Small burner test, horizontal - Determination of the horizontal flame propagation 1) Aerospace series - Cast acrylic sheets - Dimensions 2) replacement 3) 3 Terms and definitions For the
20、purposes of this standard, the terms and definitions given in IS0 8402 and the following apply. 3.1 production batch 3.1 .I sheets, as cast a production batch of as cast acrylic sheet represents the quantity of material manufactured in one continuous production run according to an established manufa
21、cturing process using identical batches of raw materials, additives, etc. 3.1.2 sheets, stretched a production batch of multi-axial orientated (stretched/pressed) acrylic sheet represents the quantity of sheets of one specific thickness produced according to an established manufacturing process usin
22、g one batch of as cast acrylic sheet 3.2 qualification testing a test or a series of tests to demonstrate that the product sample submitted for qualification satisfies the requirements specified in the standard 3.3 acceptance testing testing to demonstrate that the quality characteristics of a produ
23、ct batch conform to the quality characteristics of a qualified type 4 Requirements 4.1 Materials The requirements are specified in the relevant EN material standards. The acrylic material shall be cast polymethyl methacrylate, modified by means of a cross-linking agent, if applicable, and polymerise
24、d in a casting process. Stretched acrylic material shall be produced by subsequent multi-axial stretching or pressing. 4.2 Dimensions In accordance with EN 4367 1) Published as AECMA Prestandard at the date of publication of this standard 2) In preparation at the date of publication of this standard
25、 3) Published by: American Society for testing and Materials (ASTM), 1916 Race Street, Philadelphia, PA 19103, USA Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license f
26、rom IHS-,-,-Page 5 prEN 4243: 2001 Optical deviation according to EN 2155-7 130“ max. 3 max. I 6 max. l IO max. i 4.3 Colour 4.3.1 Colourless material The material shall be of colourless appearance when viewed through the cast surface. 4.3.2 Coloured material Coloured material will be supplied subje
27、ct to agreement between user and manufacturer. Optical defects Optical distortionlgradient according to EN 21 55-8 1 : 17 Angle of optical incidence: 60“ Discontinuity: d = 0,5 mm max. In accordance with 4.4.2,4.4.3 and 4.4.3.1 I : 12 Angle of optical incidence: 45“ Discontinuity: d = 0,5 mm max. An
28、gle of optical incidence: O“ Discontinuity: d = 0,5 mm max. In accordance with 4.4.2,4.4.3 1:12 and 4.4.3.2 4.4 Optical properties 4.4.1 Optical quality classification See table 1. Table 1 -Optical quality classification 4.4.2 General requirements The sheets shall have a high finish and be free from
29、 crazes and significant scratches. However, light scratches which are easily removed by hand polishing are acceptable. 4.4.3 Optical defects a) Minor - bubbles, foreign matter and surface defects from 0,15 mm2 to 0,4 mm2 b) Major - bubbles, foreign matter and surface defects from 0,4 mm2 to 0,5 mm2;
30、 - hairs and fibres from 0,5 mm to 3 mm in length. 4.4.3.1 Sheets containing major or minor defects, inspected as in EN 2155-6, shall be acceptable provided that: I) any area of the sheet enclosed by a circle of 150 mm radius contains no more than one major defect and or 2) any area of the sheet enc
31、losed by a circle of 150 mm radius, without a major defect, contains no more Optical defects for classifications A and B no minor defects, than 3 minor defects. Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduc
32、tion or networking permitted without license from IHS-,-,-Page 6 prEN 4243: 2001 Any accumulation of defects smaller than those defined in clause 4.4.3 a) or individual defects greater than those defined in 4.4.3 b) shall be subject to agreement between user and manufacturer. 4.4.3.2 The frequency o
33、f all defects for classifications C and D shall be subject to agreement between the user and manufacturer. Optical defects for Classifications C and D 4.4.4 Optical defects after heating The above optical tests shall normally be carried out on sheet that has not been heated. However, when required b
34、y the purchaser, the optical quality of unstretched sheet can be assessed as follows: One sheet per batch shall be suspended for a period of time T4) in an oven preheated to a temperature of (145 f 5) OC unless otherwise specified following which it will be cooled to ambient and inspected for optica
35、l defects as per EN 2155-6 (according to table 1 of EN 4243). Should the first sheet fail to satisfy the above acceptance criteria, the test shall be repeated on a second sheet. Should the second sheet fail to satisfy the acceptance criteria, the batch shall not be accepted against this clause. 4.4.
36、5 Yellowness index after heating When required by the purchaser, one sample per batch of unstretched sheet shall be heated as described in clause 4.4.4. and Yellowness Index determined according to ASTM-D 1925. 4.5 Weathering When required by the purchaser weathering conditions (natural or artificia
37、l), test methods and requirements after weathering shall be subject to agreement with the supplier. 4.6 Required characteristics The required test methods and frequency of testing are specified in table 2. 5 Quality assurance See EN 2000 and EN 3042. 5.1 Qualification testing For material qualificat
38、ion, all the required values of the material standard shall be demonstrated and documented by the manufacturer performing all the tests to the test methods given in table 2. The number of batches to be tested shall be in accordance with the material standard. These tests shall be performed before th
39、e first delivery. No changes shall be made to the composition of the material and the manufacturing process, otherwise further qualification testing is required. Should the manufacturer not be in a position to perform the required tests, due to the lack of test facilities, they may be carried out by
40、 an approved materials testing facility. Separate qualification testing is required for materials supplied in the following thickness bands: As cast: I 10 mm; 10 mm to 20 mm; 20 mm to 35 mm; 35 mm. 4) T = 1 O + (3 x a, where d = thickness of sheet in mm, and T = time in minutes Copyright Association
41、 Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page 7 prEN 4243: 2001 Stretched: I7 mm; 7 mm to 12 mm; 12 mm to 20 mm; 20 mm. Qualification of any one thickness within eac
42、h band qualifies the material for the whole of this thickness band. 5.2 Acceptance testing 5.2.1 Sampling and testing Samples for acceptance testing according to table 2 shall be taken at the frequency as defined in the material standard and tested against the requirements of 4.1 to 4.5. , 5.2.2 Cer
43、tificate of conformity For each delivery, the manufacturer shall confirm compliance to the requirements of the material standard by means of a Certificate of Conformity (for example, see Annex A) for each production batch. 6 Protection and packaging Each sheet shall be provided with a suitable prote
44、ctive covering (plastic film or paper) on both sides, which is easily removable without damaging the surface. This covering shall protect the surfaces against damages during delivery, storage, handling and cutting to size and shall not cause any degradation. Unless otherwise agreed with the customer
45、, sheet shall be packed separated according to thickness and size. The packaging shall be such that the material retains its original condition whilst protected. 7 Marking 7. I Sheets Sheets shall be appropriately marked on the protective covering with the following information: - designation accord
46、ing to EN 4367, - name of manufacturer or manufacturers identification mark including colour reference, if applicable (as agreed at qualification), - production batch number or manufacturers reference. 7.2 Packages Packages shall be marked with the following information: - designation according to E
47、N 4367, - name of manufacturer or manufacturers identification mark (as agreed at qualification). Copyright Association Europeene des Constructeurs de Materiel Aerospatial Provided by IHS under license with AECMANot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page
48、8 prEN 4243: 2001 Column 1 2 3 Table 2 - Tests 4 Line No. Properties Tensile stress at yield/at break Tensile strain at yield/at break bc Modulus of elasticity e Number of test specimens for qualification testing acceptance testing a Test to IS0 527-2 Specime; Type 1B IS0 179/1fU I I - 5 5 5 10 - -
49、- 1.4 2 Impact strength I Thermal properties IS0 75-2Ae Temperature of deflection under load 2.1 - 3 2.2 2.3 2*4 2.5 2.6 2.7 Vicat softening temperature IS0 306 3 3 /lo Vicat softening temperature 9 50 “Clh 3 3 Coefficient of linear thermal expansion Method B - EN 2155-12 2 3 3.1 Optical properties - Refractive index n; IS0 489 2 3.2 3.3 Visible light transmission Optical defects 3.6 I Haze _ - EN 2155-5 EN 2155-6 3.7 1 UV transmis
