1、Designation: E 1826 05Standard Specification forLow Volatile Organic Compound (VOC) Corrosion-InhibitingAdhesive Primer for Aluminum Alloys to Be AdhesivelyBonded1This standard is issued under the fixed designation E 1826; the number immediately following the designation indicates the year oforigina
2、l adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defe
3、nse.1. Scope1.1 This specification covers pigmented, sprayable, lowvolatile organic compound (VOC) corrosion-inhibiting adhe-sive primers for use on aluminum alloys that are to beadhesively bonded in the fabrication of panels for tacticalshelters. When applied to a properly prepared surface ofalumin
4、um alloy, the primer imparts corrosion resistance andforms a surface suitable for structural bonding and for coatingwith shelter paint finishes.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purp
5、ort to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B11
6、7 Practice for Operating Salt Spray (Fog) ApparatusB 209 Specification for Aluminum and Aluminum AlloySheet and PlateD 1002 Test Method forApparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Ten-sion Loading (Metal-to-Metal)D 3167 Test Method for Floating Roller Peel Res
7、istance ofAdhesivesE 864 Practice for Surface Preparation ofAluminumAlloysto be Adhesively Bonded in Honeycomb Shelter PanelsE 865 Specification for Structural Film Adhesives for Hon-eycomb Sandwich PanelsE 874 Practice forAdhesive Bonding ofAluminum Facingsto Nonmetallic Honeycomb Core for Shelter
8、Panels2.2 Federal Specifications:QQ-A-250/8d Aluminum Alloy 5052 H34 Plate and Sheet3QQ-A-250/11d Aluminum Alloy 6061 T6 Plate and Sheet32.3 Government Document:Rule 1124 Aerospace Assembly and Component Manufac-turing Operations, South Coast Air Quality ManagementDistrict43. Materials and Manufactu
9、rer3.1 The primer shall be a pigmented liquid composed of amodified epoxy phenolic or other resin system compounded tobe spray-applied to produce a continuous, uniform coatingwithout dilution.4. Physical Properties4.1 The uncured primer shall be tested as specified in 5.1and meet the requirement of
10、Table 1.4.2 Properties of Cured FilmWhen applied and cured inaccordance with 5.1.8, the cured film shall meet the require-ments of Tables 2 and 3 when tested as specified in 5.2 and 5.3.4.3 Storage StabilityPrimer stored in accordance with5.1.3 shall meet the requirements for normal- and low-tempera
11、ture floating roller peel in Table 3 when cured inaccordance with 5.1.8 and tested as specified in 5.3.7 and 5.3.8.4.4 Shelf LifeThe shelf life of the primer at 25 6 7C (776 12F) shall be at least four days.After four days, when testedaccording to 5.1.4, the primer shall meet the requirements fornor
12、mal- and low-temperature floating roller peel in Table 3when cured in accordance with 5.1.8 and tested as specified in5.3.7 and 5.3.8.4.5 Film ThicknessThe average, minimum, and maximumfilm thicknesses shall be between 0.0025 and 0.010 mm(0.0001 and 0.0004 in.) 615 % coefficient of variation.At leas
13、t1This specification is under the jurisdiction of ASTM Committee E06 onPerformance of Buildings and is the direct responsibility of Subcommittee E06.53on Materials and Processes for Durable Rigidwall Relocatable Structures.Current edition approved May 1, 2005. Published May 2005. Originallyapproved
14、in 1996. Last previous edition approved in 2000 as E 1826 00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.
15、3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-50984Available from South Coast Air Quality Management District, 9150 Flair Dr.,El Monte, CA 91731.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshoh
16、ocken, PA 19428-2959, United States.five thickness readings shall be made with no more than one inany 645 mm2(1 in.2) area.4.6 VOC ContentThe volatile organic compound (VOC)is any volatile compound containing the element of carbon,excluding methane, carbon monoxide, carbon dioxide, car-bonic acid, m
17、etallic carbides or carbonates, and ammoniumcarbonates, as stated in Rule 1124. The VOC content shallmeet the requirement in Table 1 when determined in accor-dance with 5.1.9.5. Test Methods5.1 Uncured Primer:5.1.1 Solids ContentDetermine the solids content by heat-ing a 2-g sample of thoroughly mix
18、ed primer in an ignition-losscrucible with cover at 121 6 5C (250 6 9F) for not less than90 min. Cool the crucible to room temperature in a desiccator.Weighings before and after heating shall be accurate to 60.001g. Calculate the mass of solids remaining as a percentage of theinitial sample mass as
19、follows:Percent solids content 5mass of nonvolatile residueinitial sample mass3 100 (1)5.1.2 Ash ContentPlace the crucibles containing the sol-ids content samples in a furnace at 565 6 28C (1050 6 82F)for not less than 60 min. Cool the crucible to room temperaturein a desiccator. Weighings before an
20、d after heating shall beaccurate to 60.001 g. Calculate the ash content remaining as apercentage of the solids content as follows:Percent ash content 5mass of ash residuemass of nonvolatile residue3 100 (2)5.1.3 Storage StabilityStore a sample of the primer forthree months from the date of manufactu
21、re at a temperaturerecommended by the manufacturer. The stored sample shallmeet the requirements for normal- and low-temperature float-ing roller peel in Table 3 when cured in accordance with 5.1.8and tested as specified in 5.3.7 and 5.3.8.5.1.4 Shelf LifeStore a sample of the primer for four daysat
22、 25 6 7C (77 6 13F). The aged sample shall meet therequirements for normal- and low-temperature floating rollerpeel in Table 3 when cured in accordance with 5.1.8 and testedas specified in 5.3.7 and 5.3.8.5.1.5 Film ThicknessThe cured primer film thicknessshall be determined with a eddy-current inst
23、rument as specifiedin 5.2.2.5.1.6 ColorDuring spray application, there shall be adiscernible color change for the primer thickness specified in4.5.5.1.7 SprayabilityThe primer shall be capable of beingreadily applied in accordance with the manufacturers instruc-tions to all test panels of either 606
24、1 T6 or 5052 H34 aluminumalloy (Fed. Spec. QQ-A-250/11d or QQ-A-250/8d, respec-tively, or Specification B 209) and cleaned in accordance withPractice E 864 for each of the tests described in 5.1.8-5.3.8.5.1.8 Curing PropertiesTest the cured film for the abilityto meet the requirements listed in Tabl
25、es 2 and 3. Spray theprimer onto the test panels and air dry at least 20 min at 24 65C (77 6 9F); then heat in air for 65 6 5 min at 121 6 5C(250 6 9F).5.1.9 VOC ContentThe grams of VOC per litre of primer,less water and exempt compounds per Rule 1124, shall bedetermined by the adhesive primer manuf
26、acturer in accordancewith Rule 1124 and meet the requirement for VOC content inTable 1.5.2 Cured Film:5.2.1 Test Panels and Panel Preparation Test panels shallbe either 6061 T6 or 5052 H34 bare aluminum alloy (Fed.Spec. QQ-A-250/11d or QQ-A-250/8d, respectively, or Speci-fication B 209) and cleaned
27、in accordance with Practice E 864.5.2.2 Smooth Uniform CoatingClean a 30- by 30-cm (12-by 12-in.) panel, spray to a primer thickness as specified in 4.5,and cure as specified in 5.1.8. Determine the primer thicknesswith a Fisher isoscope MP2-T3.3B (or equivalent) calibratedwith standards between 0.0
28、025 and 0.010 mm (0.0001 and0.0004 in.). The primer thickness shall meet the requirementsin 4.5 and Table 2.5.2.3 Pencil HardnessDetermine the pencil hardness ofthe cured film using the following procedure:5.2.3.1 Preparation of PencilsPrepare a set of drawingpencils ranging in hardness from 6B to 5
29、H by stripping thewood away from the end approximately 10 mm (38 in.) withoutdamaging the lead. Square the tip of the lead by holding thepencil in a vertical position and moving the lead back and forthover 400-grit or finer abrasive paper. Square the tip of the leadafter each trial.5.2.3.2 Procedure
30、Place a test panel with the cured primerapplied in a horizontal position. Push pencils of increasinghardness at a 45 angle into the coated surface of the panel untilone is found that will cut or scratch the coating. Use thenumber of this pencil to express the primer hardness.5.2.4 Environmental Resi
31、stance Test Clean three testpanels for each test described in 5.2.5-5.2.7 approximately 76by 127 mm (3 by 5 in.) in accordance with 5.2.1. Apply theTABLE 1 Physical Properties of Uncured Liquid PolymerTest RequirementSolids content,% Report onlyAsh content, % Report onlyColor Easily visible filmVOC
32、content 250 g/L maxTABLE 2 Physical Property of Cured Film on Primed SurfacesTest RequirementSmooth uniform coating 0.0025 to 0.010 mm (0.0001 to 0.0004in.)6 15 % coefficient of variationTABLE 3 Physical Properties of Bonded SpecimensTestRequirements(min)Normal-temperature lap shear, 24C (77F), MPa
33、(psi) 20.0 (2903)Low-temperature lap shear, 55C (67F), MPa (psi) 20.0 (2903)High-temperature lap shear, 93C (200F), MPa (psi) 13.0 (1890)Humidity exposure lap shear, 93C (200F), MPa (psi) 8.0 (1161)Salt spray exposure lap shear, 35C (95F), MPa (psi) 16.0 (2322)Normal-temperature floating roller peel
34、 strength, 24C (75F),N/m (lbf/in.)4400 (25.1)Low-temperature floating roller peel strength, 55C (67F),N/m (lbf/in.)2625 (15.0)E1826052primer and cure in accordance with 4.5 and 5.1.8. The primedpanels shall be subjected to the environments specified in5.2.5-5.2.7 and there shall be no cracking, no b
35、listering, and aminimum pencil hardness of 4H.5.2.5 Water ResistanceImmerse the panels with the curedprimer coating in distilled water for seven days at 24 6 3C (756 5F) and then expose to 95 to 100 % relative humidity at 506 3C (121 6 5F) for 30 days.After exposure the panels shallmeet the requirem
36、ents in 5.2.4, and there shall be no loss ofadhesion as described in 5.2.8.5.2.6 Heat ResistanceHeat test panels prepared as in 5.2.4at 120 6 3C (248 6 5F) for 70 h. After exposure the panelsshall meet the requirements in 5.2.4, and there shall be no lossof adhesion as described in 5.2.8.5.2.7 Corro
37、sion ResistanceScribe test panels prepared inaccordance with 5.2.4 through the coating to the base metalwith two diagonal scribe marks extending from corner tocorner and then expose them to 5 % salt fog in accordance withPractice B117for 40 days. After exposure the panels shallmeet the requirements
38、in 5.2.4, and there shall be no under-cutting of the primer along the scribe lines.5.2.8 Loss of Adhesion:5.2.8.1 Thoroughly dry the panel by wiping with a clean drycheesecloth. Conduct the test at 20 to 27C (68 to 81F).5.2.8.2 Scribe two parallel scratches 25 mm (1 in.) apartthrough the coating dow
39、n to the metal with a sharp edgedscribe.5.2.8.3 Apply a strip of 25-mm (1-in.) wide masking tape(not more than five months old from date of manufacture)across the scratches at 90 to the scribe lines in the panel areato be tested. Press the tape down using two passes of a 2-kg(4.4-lb) rubber-covered
40、roller approximately 90 mm (3.5 in.) indiameter by 44.5 mm (1.75 in.) in width. The durometer of theroller surface shall be 70 to 80 Shore A.5.2.8.4 As an alternative to 5.2.8.3, the tape shall be presseddown by rolling the tape roll along the strip of applied tapeusing a firm hand pressure of appro
41、ximately 2 kg (4.4 lb).5.2.8.5 Remove the tape in one abrupt motion perpendicularto the panel. No primer shall be removed from the panel, otherthan that previously removed during the scribing procedure in5.2.8.2.5.3 Bonding Property Tests:5.3.1 Preparation of Test Specimens Prepare five speci-mens i
42、n accordance with Practice E 864 for each of the tests inTable 3. The lap shear specimens shall be in accordance withTest Method D 1002 and the peel specimens in accordancewith Test Method D 3167. The adherents shall be of either6061 T6 or 5052 H34 aluminum alloy. Apply the primer andallow to air dr
43、y for not less than 20 min at 25 6 5C (78 69F); follow by heating at 121 6 5C (250 6 9F) for 65 6 5min. Bond and cure in accordance with Specification E 865.5.3.2 Normal-Temperature Lap ShearSubject each speci-men to a lap shear test at 25 6 3C (77 6 5F) in accordancewith Test Method D 1002.5.3.3 Lo
44、w-Temperature Lap ShearTest each specimen inaccordance with Test Method D 1002 for low-temperature lapshear at 55 6 3C (66 6 5F). Bring the temperature of thespecimen to 55 6 3C (66 6 5F) as indicated by athermocouple at the bond area and stabilize for 10 min prior totest. The test chamber used to t
45、est the specimens shall bestabilized at the test temperature for at least 45 min prior totesting.5.3.4 High-Temperature Lap ShearTest each specimen inaccordance with Test Method D 1002 for high-temperature lapshear at 93 6 3C (200 6 5F). Bring the temperature of thespecimen to 93 6 3C (200 6 5F) as
46、indicated by athermocouple at the bond area and stabilize for 10 min prior totest. The test chamber used to test the specimens shall bestabilized at the test temperature for at least 45 min prior totesting.5.3.5 Humidity Exposure Lap ShearTest each specimen inaccordance with Test Method D 1002 at 93
47、 6 3C (200 6 5F)for lap shear strength after two weeks exposure at 95 6 5%relative humidity at 71 6 3C (160 6 5F).After removing thespecimens from the humidity cabinet, place them and a wetpaper towel in a sealed plastic bag. Bring the temperature ofthe specimen to 93 6 3C (200 6 5F) as indicated by
48、 athermocouple at the bond area. Stabilize the specimen 2 minprior to test. Test the specimens within 24 h after removal fromthe humidity cabinet. The test chamber used to test thespecimens shall be stabilized at the test temperature for at least45 min prior to testing.5.3.6 Salt Spray Exposure Lap
49、Shear Test each specimenin accordance with Test Method D 1002 after exposure for twoweeks to salt spray using 5 % NaCl solution at 35 6 1C (956 2F) in accordance with Practice B117.5.3.7 Normal-Temperature Floating Roller Peel StrengthTest each specimen in accordance with Test Method D 3167.The test temperature shall be 25 6 3C (77 6 5F).5.3.8 Low-Temperature Floating Roller Peel StrengthTesteach specimen according to Test Method D 3167. The testtemperature shall be 55 6 3C (66 6 5
