1、Designation: F 502 02Standard Test Method forEffects of Cleaning and Chemical Maintenance Materials onPainted Aircraft Surfaces1This standard is issued under the fixed designation F 502; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revisi
2、on, 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 Defense.1. Scope1.1 This test method cov
3、ers determination of the effects ofcleaning solutions and liquid cleaner concentrates on paintedaircraft surfaces (Note 1). Streaking, discoloration, and blister-ing may be determined visually. Softening is determined witha series of specially prepared pencils wherein determination ofthe softest pen
4、cil to rupture the paint film is made.NOTE 1This test method is applicable to any paint film that is exposedto cleaning materials. MIL-PRF-85285 has been selected as a basicexample. When other paint finishes are used, refer to the applicablematerial specification for panel preparation and system cur
5、ing prior totesting.1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this st
6、andard 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:D 329 Specification for Acetone2D 1193 Specification for Reagent Water32.2 Military Standards:4MIL-PRF-85285 Coating: Polyure
7、thane, High SolidsA-A-58054 Abrasive Mats, Non-Woven Non-MetallicMIL-PRF-23377 Primer Coatings: Epoxy, High SolidsMIL-C-81706 Chemical Conversion Materials for CoatingAluminum and Aluminum Alloys2.3 Federal Standards:4FED-STD-595 Colors Used in Government Procurement2.4 Industry Standards:5SAE-AMS-Q
8、Q-A-250/13 Aluminum Alloy Alclad 7075,Plate and Sheet3. Materials3.1 Drawing Pencils (Note 2)6B, 5B, 4B, 3B, 2B, B, HB,F, H, 2H, 4H, 5H, and 6H.3.2 Fine Sand Paper, 180 to 320 grit.3.3 Abrasive Mats, A-A-58054, aluminum oxide, fine orvery fine.3.4 Acetone, in accordance with Specification D 329.3.5
9、MIL-PRF-85285 Coating, polyurethane, aliphatic,weather-resistant, FED-STD-595 Color No. 17875, insigniawhite.3.6 MIL-PRF-23377 Primer Coating, epoxy polyamide,chemical- and solvent-resistant.3.7 Chemical Conversion Materials, MIL-C-81706, Class1A, for coating aluminum and aluminum alloys.3.8 Distill
10、ed or Deionized Water, in accordance with Speci-fication D 1193, Type IV.NOTE 2All pencils in a set must be from one manufacturer (forexample, Venus, Eagle, and so forth).4. Safety Precautions4.1 All safety regulations prescribed for spray application ofpolyurethane paints shall be strictly adhered
11、to in the use of thistest method.4.2 The testing procedure shall be conducted in a well-ventilated area.5. Test Specimens5.1 SAE-AMS-QQ-A-250/13 Aluminum Alloy Alclad7075-T6, Plate and Sheet.6. Test Solutions6.1 Concentrated (as received, if a liquid).1This test method is under the jurisdiction of A
12、STM Committee F07 onAerospace and Aircraft and is the direct responsibility of Subcommittee F07.07 onQualification Testing of Aircraft Cleaning Materials.Current edition approved Aug. 10, 2002. Published September 2002. Originallypublished as F 502 77. Last previous edition F 502 93(1998)e1.2Annual
13、Book of ASTM Standards, Vol 06.04.3Annual Book of ASTM Standards, Vol 11.01.4Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, Attn: NPODS.5Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrenda
14、le, PA 15096-0001.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.2 In use dilution, if diluent is water, see 3.8.7. Procedure7.1 Preparation of PencilsPrepare a set of drawing pen-cils for testing the painted panels by stripping t
15、he wood awayfrom the end approximately38 in. without damaging the lead(as shown in Fig. 1). Then square the tip of the lead by holdingthe pencil in a vertical position and moving the lead back andforth over a very fine (180- to 320-grit) sandpaper. Square thetip of the lead after each trial.7.2 Prep
16、aration of PanelsWipe 3- by 6- by 0.02-in. (76-by 152- by 0.5-mm) aluminum panels with acetone, dry andabrade lightly with a fine aluminum oxide mat. Rinse thesurface with distilled water and coat with a conversion coatingmaterial conforming to MIL-C-81706, Class 1A. Apply onecoat of MIL-PRF-23377 e
17、poxy primer, 0.6 to 0.8 mil (0.015 to0.020 mm) and allow to dry1hatroom temperature. Apply amist coat of the designated polyurethane and allow to dry 30min at room temperature. Apply the finish coat in threeapplications of 0.4 to 0.6 mil (0.010 to 0.015 mm), allowing a1-h drying time at room tempera
18、ture between each coat. Allowthe painted panels to dry four days at room temperature; thenbake for 24 h at 180F (82C) or allow panels to air dry anadditional three to ten days at room temperature. No greaterthan one pencil hardness difference between coated panelsprepared from the same batch of pain
19、t at the same time shall bepermitted.7.3 Procedure:7.3.1 Place the test panels in a horizontal position in an ovenmaintained at 100 6 5F (38 6 2C). Apply the test solutionto approximately one half the area of each panel and allow toremain on the panels for 30 min. Then remove the panels fromthe oven
20、 and rinse with distilled or deionized water and allowto air dry for 24 h. Examine for streaking, discoloration, orblistering of the finish.7.3.2 Determine the hardness of the treated and untreatedareas in the following manner: Hold pencils of decreasinghardness by hand at a 45 angle (see Fig. 1) an
21、d push across thepaint film with a firm uniform pressure until a pencil is foundthat will not cut the film but will leave a black mark on thesurface, whereas the next hardest pencil will cut through thefilm without leaving a black mark. The hardness number of thepencil that cuts the film shall expre
22、ss film hardness. Make atleast three determinations on both exposed and unexposedportions of the coated panel.8. Report8.1 The report shall include the following:8.1.1 The appearance of the panels after exposure,8.1.2 The pencil hardness required to rupture the paint filmon the unexposed portion of
23、the panel, and8.1.3 The pencil hardness required to rupture the paint filmon the exposed portion of the panel.9. Precision and Bias9.1 No statement as to precision and bias can be made asstandard materials do not exist for comparative tabulationpurposes.10. Keywords10.1 aircraft; effect; painted sur
24、facesASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights
25、, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional st
26、andardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Co
27、mmittee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).FIG. 1 Test for Hardness of Painted SurfaceF502022
