1、ASD STANDARD NORME ASD ASD NORM prEN 4473 Edition P 2 September 2009 PUBLISHED BY THE AEROSPACE AND DEFENCE INDUSTRIES ASSOCIATION OF EUROPE - STANDARDIZATIONAvenue de Tervuren, 270 - B-1150 Brussels - Tel. + 32 2 775 8126 - Fax. + 32 2 775 8131 - www.asd-stan.orgICS: Supersedes edition P 1 of Febru
2、ary 1999 Descriptors: ENGLISH VERSION Aerospace series Aluminium pigmented coatings for fasteners Technical specification Srie arospatiale Revtements alumino-organiques pour fixations Spcification technique Luft- und Raumfahrt Aluminium pigmenttete Beschichtungen fr Fixierungen Technische Lieferbedi
3、ngungen This “Aerospace Series“ Prestandard has been drawn up under the responsibility of ASD-STAN (The AeroSpace and Defence Industries Association of Europe - Standardization). It is published for the needs of the European Aerospace Industry. It has been technically approved by the experts of the
4、concerned 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
5、 formal agreement of ASD-STAN, it will be submitted as a draft European Standard (prEN) to CEN (European Committee for Standardization) for formal vote and transformation to full European Standard (EN). The CEN national members have then to implement the EN at national level by giving the EN the sta
6、tus of a national standard and by withdrawing any national standards conflicting with the EN. Edition approved for publication 30 September 2009 Comments should be sent within six months after the date of publication to ASD-STAN Mechanical Domain Copyright 2009 by ASD-STAN prEN 4473:2009 (E) 2 Conte
7、nts Page Foreword2 1 Scope 3 2 Normative references 3 3 Terms and definitions .4 4 Technical specifications .5 5 Quality assurance5 6 Requirements.5 Annex A (normative) Test coupons for paint adhesion test 11 Annex B (normative) Test specimen for ohmic resistance measurement. 12 Annex C (normative)
8、Lightning current simulation and swept lightning. 13 C.1 Lightning current simulation . 13 C.2 Test specimens distribution 13 C.3 Swept lightning (on countersunk head fastener) 13 C.4 Lightning current transfer condition (on protruding head fastener). 14 Foreword This standard was reviewed by the Do
9、main Technical Coordinator of ASD-STANs Mechanical Domain. After inquiries and votes carried out in accordance with the rules of ASD-STAN defined in ASD-STANs General Process Manual, this standard has received approval for Publication. prEN 4473:2009 (E) 3 1 Scope This standard defines the qualifica
10、tion test conditions for aluminium pigmented coatings applicable to fasteners in titanium, titanium alloys, nickel base alloys and corrosion resisting steels. The aluminium pigmented coatings are not applicable to fasteners in non-corrosion resistant steels. Temperature class: 315 C 1)Type I : Coati
11、ng with chromate and a cetyl alcohol lubricant. Type II : Coating without chromate and an cetyl alcohol lubricant. Type III : Coating with chromate, no additional lubricant. Type IV : Coating without chromate, no additional lubricant. 2 Normative references The following referenced documents are ind
12、ispensable 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. ISO 2409, Paints and varnishes Cross cut test. ISO 9227, Corrosion tests in artificial atmo
13、spheres Salt spray tests. EN ISO 2812-1, Paints and varnishes Determination of resistance to liquids Part 1: Immersion in liquids other than water. EN 3032, Aerospace series Test method for dry film lubricants Thickness measurement. EN 4474, Aerospace series Aluminium pigmented coatings Coating meth
14、ods. 2)EN 6117, Specification for bolts with cetyl alcohol. 2)EN 9133, Aerospace series Quality management systems Quality Procedure for Aerospace Standards Parts. TR 4676, Aluminium pigmented coatings List of commercial products.3)NASM 1312-5, Fastener Test Methods; Method 5: Stress durability. 4)N
15、ASM 1312-12, Fasteners Test Methods, Method 12: Thickness of metallic coatings. 4)MIL-A-8625, Anodic coatings for aluminium and aluminium alloys. 5)1) Maximum operating temperature. 2) Published as ASD Prestandard at the date of publication of this standard. 3) Published as ASD Technical Report at t
16、he date of publication of this standard. 4) Published by: Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928, USA. 5) Published by: Department of Defense (DOD), the Pentagon, Washington, D.C. 20301 USA. prEN 4473:2009 (E) 4 3 Terms and definitions For the p
17、urposes of this document, the following terms and definitions apply. 3.1 production lot product quantity of known composition (aluminium pigmented resin) prepared as one mixing using the same equipment 3.2 seam open surface defect 3.3 blister local convexity caused by a sub-surface inclusion of gas
18、or liquid 3.4 nodule localized buildup or unmixed solid particles 3.5 pit void, hole in the surface as caused, for example, by corrosion 3.6 porosity fine holes or pores within the coating 3.7 functional surfaces functional surfaces are defined as surfaces in contact with mating structure and thread
19、ed portion such as screws: under head bearing surface, shank, lead-in radius and thread surface if applicable; nuts: bearing surfaces, thread surface; spherical washers: bearing surfaces; swaged collars: all surfaces. 3.8 generic part familly of similar parts such as: screws; nuts and threaded colla
20、rs; lockbolts; swaged collars; solid rivets; blind bolts; bushes; spherical washers. prEN 4473:2009 (E) 5 4 Technical specifications 4.1 Product TR 4676 gives the list of aluminium pigmented coating commercial products. Product to be applied shall conform to environmental, work safety and public hea
21、lth European regulations. 4.2 Product composition The preparation method and product composition shall be defined by the manufacturer. The latter must peremptorily notify its users of any change subsequent to qualification. The product shall not contain chemical compounds as listed below : lead, gra
22、phite, type II and IV shall not contain hexavalent chromate. 4.3 Product application Product must be applied in accordance with EN 4474. The resin curing temperature must be lower than the last ageing treatment of the material to be coated by at least 10 C. Product may be applied in several coats bu
23、t shall only have one curing (polymerization), pre heating (flash-off) is acceptable for each coat. 5 Quality assurance 5.1 Qualification EN 9133 All coating qualification tests shall be done on fasteners and according to Table 1. For fastener qualification only paragraphes 6.1 to 6.3 apply. 5.2 Acc
24、eptance Acceptance is done through fasteners lots for appearance, thickness and adhesion. Sampling 3 per generic part or coating application process and test method in accordance with sections 6.1 (Appearance), 6.2 (Thickness) and 6.3 (Adhesion). 6 Requirements See Table 1. All the tests are to be c
25、arried out after application according to EN 4474. When cetyl alcohol is added to type III or IV, they shall be qualified according to type I or II. prEN 4473:2009 (E) 6 Table 1 Section Characteristic Requirement Inspection and test method Sampling for qualification 6.1 Appearance The coating shall
26、be smooth, uniform color, and shall be free of pinholes, porosity, blisters, nodules, pits, or other harmful imperfections. Visual examination 10 per generic part External threaded fasteners:The coating thickness shall be between 5 m and 13 m on all functional surfaces as defined in 3.7. Determinati
27、on of coating thickness shall be made by any of the methods specified in NASM 1312-12. 6.2 Thickness Internal threaded fasteners: The coating thickness shall be between 5 m and 20 m on all functional surfaces as defined in 3.7. In case of conflict the micrographic examination shall be chosen. 10 per
28、 generic partor coating application process 6.3 Adhesion The coating must remain continuously bonded to the basis material. Class 0 ISO 2409 If fastener geometry does not alllow ISO 2409 adhesion test, the coating must be cut through to the base material on the largest plain surface of the part. Pre
29、ss the tape firmly to the cut on the plain surface of the fastener and remove the tape in one abrupt motion perpendicular to the fastener surface. Any evidence of coating separation when examined at approximately 4X is cause for rejection. 5 per generic part, material type or coating application pro
30、cess 6.4 Heat resistance The coating must remain continuously bonded to the basis material. No powder shall be detected by visual inspection. Class 0 Expose the coated test part to 315 C for 4 h. Air cool and carry out the adhesion test (see 6.3). ISO 2409. 4 screws continued prEN 4473:2009 (E) 7 Ta
31、ble 1 (continued) Section Characteristic Requirement Inspection and test method Sampling for qualification Immersion according to EN ISO 2812-1 inside : Kerosene: Method 1 = Full immersion 1 000 h at 70 C min in Kerosene or equivalent containing 0,2 % methyl cellosolve; Hydraulic fluid: Method 1 = F
32、ull immersion 1 000 h at 70 C min in phosphate ester hydraulic fluid type IV A. 6.5 Resistance to fuels and hydraulic fluids The coating shall not show evidence of blistering or loss of adhesion. Class 0 Adhesion test as per ISO 2409 2 screws Immersion of the coated test pieces: 24 h at room tempera
33、ture in three products: benzylic alcohol and dimer acid; diestone. 6.6 Resistance to stripper agents and to solvents The coating shall no show evidence of blistering or loss of adhesion. Class 0 Adhesion test as per ISO 2409 2 screws 6.7 Embrittlement 72 h at a tensile load of 80 % of minimum specif
34、ied UTS, fasteners shall withstand the imposed loading conditions without any breaking or craking. NASM 1312-5 4 screws per material type identified as sensitive 6.8 Galvanic corrosion The countersinks and the surface area of the aluminium blocks around the coated fasteners shall show, by visual obs
35、ervations, no more corrosion than the corresponding areas with the cadmium plated fastener control blocks. General surface corrosion on the back of the panels shall not be considered in evaluating the protective qualities of the coating. Place coated countersunk head titanium bolts in a 7075 T6 alum
36、inium alloy block defined in Annex A. The assembled block shall be exposed for 336 h in neutral salt spray (NSS) ISO 9227. 3 screws continued prEN 4473:2009 (E) 8 Table 1 (continued) Section Characteristic Requirement Inspection and test method Sampling for qualification Place coated countersunk hea
37、d bolts in a 7075 T6 aluminium alloy block defined in Annex A: Specimen manufacture: plate shall be anodised and coated with aircraft primer paint prior to drilling and countersinking; fastener installation; appropriate solvent cleaning + scouring pad + tack rag + chromate free external paint scheme
38、. Tests preparation: Cross cut according to ISO 2409. Adhesion tests: 6.9 Paint Adhesion Class 0 at initial stage Class 3 after water immersion on initial stage; after water immersion 336 h at room temperature (Distilled or deionised water with 5,5 1 M.cm). 6 screws 6.10 Electrical conductivity and
39、lightning The ohmic resistance shall be below 10 m. No overheating above 50 C shall be detected. No sparking shall occurrs during lightning test. The lightning test is not mandatory. Tests to be performed on 4,8 mm bolt diameter with interference of (40 10) m. The coating to qualify shall be applied
40、 to the element on which it is applicable (bolt, nut, lockbolt, collar, ). In case the coating shall be qualified on bolt, the nut to be used shall be cadmium plated steel. In case the coating shall be qualified on lockbolt, the collar to be used shall be Chemical Conversion Coating on aluminium. In
41、 case the coating shall be qualified on nut, the bolt to be used shall be Resin Based Aluminium on titanium. Ohmic resistance to be measured between points A and B (see specimen in Annex B) under a current of 10 A. Swept lightning current and lightning current transfer in accordance with Annex C. 48
42、 per generic part continued prEN 4473:2009 (E) 9 Table 1 (continued) Section Characteristic Requirement Inspection and test method Sampling for qualification 6.11 Interference fit This test is only applicable to the following generic parts: screws; lockbolts. Types I and II: The average of the 5 ins
43、tallations shall have an installation force of 34 000 N or less, without a single installation force higher than 37 000 N. Types III and IV: The average of the 5 installations shall have an installation force of 11 000N or less, without a single installation force higher than 13 000 N. For all coati
44、ng types, insertion load versus travel F = f (l) curves shall be recorded and shall not present any discontinuities except at the interface. The removal load shall not exceed more than 25 % of the highest value measured during installation. Cetyl alcohol additional lubrication per EN 6117. Types I a
45、nd II: Five samples of 12,7 mm (1/2“) diameter fasteners shall be coated per the requirements of this specification. Samples shall be installed in two 7075 T6 plates 25,4 mm thick each (both plates must be positioned and then assembled prior to holes drilling and chamfering). Hole surface texture Ra
46、 0,8 m. Interference fit shall be (145 10) m. The edges of the holes shall be chamfered to a diameter up to 1,40 mm larger than the hole. A radius up to 0,9 mm shall be applied to the chamfer edges. Type III and IV: Five samples of 6,35 mm (1/4“) diameter fasteners shall be coated per the requiremen
47、ts of this specification. Samples shall be installed in two 7075 T6 plates 12,7 mm thick each (both plates must be positioned and then assembled prior to holes drilling and chamfering). Hole surface texture Ra 0,8 m. Interference fit shall be (50 10) m. The edges of the holes shall be chamfered to a
48、 diameter up to 1,20 mm larger than the hole. A radius up to 0,7 mm shall be applied to the chamfer edges. 5 screws or lockbolts continued prEN 4473:2009 (E) 10 Table 1 (continued) Section Characteristic Requirement Inspection and test method Sampling for qualification 6.12 Labelling Product must be
49、 identified with a label upon which is legibly recorded: product designation; production lot number; manufacturing date; shelf-life; manufacturers name and address; certificate of conformity. Visual examination Non applicable 6.13 Delivery Product delivery must precede by at least one year the shelf-life. Product must be accompanied by Material Safety Data Sheet in compliance with country specific regulation. Visual examination Non applicable prEN 4473:2009 (E
