1、Designation: D 1654 08Standard Test Method forEvaluation of Painted or Coated Specimens Subjected toCorrosive Environments1This standard is issued under the fixed designation D 1654; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 covers t
3、he treatment of previouslypainted or coated specimens for accelerated and atmosphericexposure tests and their subsequent evaluation in respect tocorrosion, blistering associated with corrosion, loss of adhesionat a scribe mark, or other film failure.1.2 The values stated in SI units are to be regard
4、ed as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of whoever uses this standard to consult andestablish appropriate safety and health practices a
5、nd deter-mine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B117 Practice for Operating Salt Spray (Fog) ApparatusD 610 Practice for Evaluating Degree of Rusting on PaintedSteel SurfacesD 714 Test Method for Evaluating Degree of Blistering ofPain
6、tsD 822 Practice for Filtered Open-Flame Carbon-Arc Expo-sures of Paint and Related CoatingsD 870 Practice for Testing Water Resistance of CoatingsUsing Water ImmersionD 1014 Practice for Conducting Exterior Exposure Tests ofPaints and Coatings on Metal SubstratesD 1735 Practice for Testing Water Re
7、sistance of CoatingsUsing Water Fog ApparatusD 2247 Practice for Testing Water Resistance of Coatings in100 % Relative HumidityD 2803 Guide for Testing Filiform Corrosion Resistance ofOrganic Coatings on MetalD 4141 Practice for Conducting Black Box and Solar Con-centrating Exposures of CoatingsD 45
8、85 Practice for Testing Water Resistance of CoatingsUsing Controlled CondensationD 4587 Practice for Fluorescent UV-Condensation Expo-sures of Paint and Related CoatingsD 5894 Practice for Cyclic Salt Fog/UV Exposure ofPainted Metal, (Alternating Exposures in a Fog/Dry Cabi-net and a UV/Condensation
9、 Cabinet)D 6695 Practice for Xenon-Arc Exposures of Paint andRelated CoatingsD 7087 Test Method for An Imaging Technique to MeasureRust Creepage at Scribe on Coated Test Panels Subjectedto Corrosive EnvironmentsE3 Guide for Preparation of Metallographic SpecimensG85 Practice for Modified Salt Spray
10、(Fog) TestingG87 Practice for Conducting Moist SO2Tests2.2 ANSI Standard:3B94.50 Single-Point Cutting Tools, Basic Nomenclatureand Definitions for3. Terminology3.1 paint removal material, na device or substance that isused to remove loose coating around a scribe.3.2 rust creepage or undercutting, nc
11、orrosion of a sub-strate that occurs around a damaged area of a coated material.3.3 scribe, na linear, intentionally prepared damaged areaon a coated material that extends down to the substrate.3.4 scribing tool, na tool used to prepare a scribe on acoated material.3.5 zone of corrosion, narea of co
12、rrosion of a substrate.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.25 on Evaluation of Weathering Effects.Current edition approved Nov. 1, 2008. Published December 2008
13、. Originallyapproved in 1959. Last previous edition approved in 2005 as D 1654 05.2For 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 pag
14、e onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Significance and Use4.1 This metho
15、d provides a means of evaluating and com-paring basic corrosion performance of the substrate, pretreat-ment, or coating system, or combination thereof, after exposureto corrosive environments.5. Apparatus5.1 Scribing Tools:5.1.1 Lathe Tool TypeHigh speed tool steel or tungstencarbide thread cutting
16、lathe tool bit with a cutting tip having a60 included angle. ANSI B94.50, Style E has been found tomeet these requirements. (See Fig. 1.) The tool bit is typicallymounted in a holder such as a wooden file handle to facilitatethe scribing operation.5.1.2 Pencil TypePencil shaped device, with a high s
17、peedtool steel or tungsten carbide scribing tip. Typically thegripping surface is knurled. The tip may be replaceable orpermanent.5.1.3 Motorized Circular BladeA motor fitted witha1to2 mm wide circular cutting device.5.1.4 Other TypesOther types of scribing instrumentswhich use a knife type blade su
18、ch as a scalpel, razor blade, boxcutter knife, or other sharp pointed tool are acceptable if agreedupon between the producer and the user.5.2 StraightedgeAny straightedge of sufficient length andrigidity to guide the scribing tool in a straight line.5.3 Paint Removal MaterialsThe following materials
19、 canbe used to remove the coating around the scribe.5.3.1 Spatula.5.3.2 Knife or similar instrumentthe sharpness of bladeshall be agreed upon between purchaser and seller.5.3.3 Paint Stripper or strong solvent.5.3.4 Materials for removal by air:5.3.4.1 Air SourceA source of compressed air capable of
20、delivering at least 4.72 L/s (10 ft3/min) at 552 kPa (80 psi).5.3.4.2 Air GunAn air dusting gun and nozzle combina-tion. The following configuration has been found to be suc-cessful:Air Consumption,m3/min (ft3/min)Pressure, kPa(psi)Nozzle Diameter,mm (in.)0.24 (8.4) 550 (80) 3.0 (0.12)5.3.5 Power Wa
21、sher capable of delivering 3500 psi.5.4 ScaleAny rule with 1-mm divisions.6. Preliminary Treatment of Test Specimens6.1 Scribed Specimens:6.1.1 Where specified or agreed upon, prepare each speci-men for testing by scribing it in such a manner that the scribecan be exposed lengthwise when positioned
22、in the test cabinet.This position will allow solution droplets to run lengthwisealong the scribe.6.1.2 Scribe the specimen by holding the tool at approxi-mately a 70 to 90 angle to the surface with the upper end oftool holder inclined toward the operator. Position the tool sothat only the tip is in
23、contact with the surface. (See Fig. 2.) Pullthe scribing tool to obtain a uniform V-cut through the coatingthat is being tested. The endpoints of the scribe shall be at least1.25 cm (0.5 in.) from the edge of the panel. Inspect the toolfrequently, using low power magnification, for dulling, chip-pin
24、g or wear and replace or repair as needed. The scribe shouldbe of sufficient length to cover the significant test area, butshould not contact the edge of the specimen. The scribe mustpenetrate all organic coating layers on the metal, leaving auniformly bright line. The extent of scribe penetration t
25、hroughmetal coatings, such as galvanize, should be agreed uponbetween the producer and user. The coil coating industrytypically requires scribes to penetrate all organic coating layersbut not penetrate the metal coating layers. The automotiveindustry typically requires scribes to penetrate all organ
26、ic andmetal coating layers. The pencil type may be less effective thanthe lathe tool type when scribing coating systems consisting ofmultiple layers of organic coatings or coating systems includ-ing metal layers. When scribing coating systems consisting ofmultiple layers of organic coatings or coati
27、ng systems includ-ing metal layers the depth and quality of scribe techniqueshould be evaluated using the cross section, castable plasticmount, polishing technique described in Practice E3. Qualityof the scribe technique may also be observed with the aid oflow-power magnification. Note, mark, and de
28、scribe defects,coding, and flaws that may affect results. If a motorizedcircular blade is used, position the test specimen to allow for astraight, linear cut at the desired length. The blade shall bepositioned to a depth such that it is able to cut into thesubstrate. This type of blade will result i
29、n a rectangular cutrather than a V-cut.6.1.3 One cut may not be sufficient to cut multi-layerprotective coatings down to the metal. The use of more thanone cut must be agreed to between all concerned parties priorto scribing, and the number of cuts must be recorded in the testdocumentation. When mul
30、tiple cuts are needed, each cut mustFIG. 1 Scribe Tool FIG. 2 Scribing Tool in ActionD1654082be done in the same direction. If a motorized blade is beingused, it may be necessary to clean out residual materials of thescribe with a pencil-type scriber.6.1.4 Scribe lines other than those of a single,
31、straight naturemay be used if agreed upon between the producer and the user.6.1.5 Wipe off the panel with a dry rag, or blow with air toremove any metal flakes from the scribing process.6.1.6 The width of the scribe (w) shall be recorded.6.2 Cut EdgesCut edges of panels may be exposed duringtesting,
32、 or protected by wax, tape, or other means as agreedupon between the producer and the user. If left unprotected,method of shearing panel edges should be agreed uponbetween the producer and user, noting whether edges areoriented in the “burr up” or “burr down” configuration.6.3 DeformationDeformation
33、 of test panels prior to ex-posure, if desired, should be agreed upon between the producerand user.7. Exposure of Test Specimens7.1 Expose test specimens in accordance with one or moreof the following test methods or practices: B117, D 822,D 870, D 1014, D 1735, D 2247, D 2803, D 4141, D 4585,D 4587
34、, D 5894, D 6695, G85, G87, or any other applicabletest method, as agreed upon between the producer and the user.The length of test and evaluation intervals should be agreedupon prior to exposure of specimens.8. Procedure AEvaluation of Rust Creepage forScribed Specimens8.1 Rinse each specimen after
35、 completion of the exposureperiod, using a gentle stream of water at a temperature up to45C (110F). Remove coating along scribe with one of thefollowing methods such that all corrosion of the substrate (thatis, rust creepage or undercutting) can be observed using one ofthe following methods.8.1.1 Me
36、thod 1 (Scraping)Scrape the specimen vigor-ously with and instrument described in 5.3.1.8.1.2 Method 2 (Knife)Pick off the loose or lifted coatingwith a knife described in 5.3.2.8.1.3 Method 3 (Paint Stripper)Soak the panels in paintstripper or suitable solvent as described in 5.3.3 until thecoating
37、 around the scribe is removed, or can be removed witha spatula.8.1.4 Method 4 (Air Blow-Off)Holding the nozzle, asdescribed in 5.3.4, at approximately a 45 angle, blow alongthe entire scribe line, disturbing the surface adjacent to thescribe adjacent to the scribe mechanically by the air nozzle toen
38、sure an opening for the air blast.8.1.5 Method 5 (Power Washer)Using a power washerdescribed in 5.3.5, remove the coating around the scribe.8.1.6 Other methods can be used to remove loose materialaround the scribe if agreed upon between purchaser and seller.NOTE 1The above methods may not be appropr
39、iate in all cases, suchas for interim ratings in continuing tests.NOTE 2For all methods, complete the removal of loose coating with15 min of specimen removal from the exposure cabinet. If removal cannotbe completed within the prescribed time, immerse the specimens in waterat room temperature or stor
40、e in a plastic bag to avoid any drying effect.8.2 RatingOnly areas of the substrate that are discoloreddue to corrosion should be considered. Record the maximumand minimum creepage from the scribe, and note whether ornot the maximum is an isolated spot. The mean can bedetermined by making at least 6
41、 measurements of the width ofthe zone of corrosion uniformly distributed along the scribe,ignoring 3 mm (0.125 in.) of each end of the scribe. Determinethe arithmetic mean, and use the following equation to deter-mine rust creepage (c):c 5wc2w2(1)where:wc= mean overall width of the corrosion zone an
42、dw = width of the original scribe.As an alternative, use Test Method D 7087. Record creepvalues in millimetres, inches, or rating numbers as prescribedin Table 1, as agreed upon between producer and user. Loss ofpaint that does not extend down to the substrate and result incorrosion can be rated usi
43、ng the same procedure, but shouldnot be considered as scribe creepage, undercutting, or corro-sion. If this is the case, not the coat(s) removed.9. Procedure BEvaluation of Unscribed Areas9.1 Use photographic blister standards given in PracticeD 714 to describe the results of the exposure test with
44、respectto blisters, and Practice D 610 to describe the results of theexposure with respect to rusting10. Procedure CEvaluation of Unprotected Edges10.1 If paint creepage from cut edges is tested, rate thecorrosion or loss of paint extending from a cut edge in the samemanner described for scribes in
45、Procedure A.11. Procedure DEvaluation of Formed Areas11.1 If tested samples contain bends, dimples, or otherformed areas of interest, rate the extent of failure at these areasseparately in the same manner described in Procedure B, or asagreed upon between the producer and user.12. Report12.1 The rep
46、ort shall include the following information,unless otherwise agreed upon between the producer and user:TABLE 1 Rating of Failure at Scribe (Procedure A)Representative Mean Creepage From ScribeMillimetresInches(Approximate)RatingNumberZero 0 10Over 0 to 0.5 0 to164 9Over 0.5 to 1.0164 to132 8Over 1.0
47、 to 2.0132 to116 7Over 2.0 to 3.0116 to18 6Over 3.0 to 5.018 to316 5Over 5.0 to 7.0316 to14 4Over 7.0 to 10.014 to38 3Over 10.0 to 13.038 to12 2Over 13.0 to 16.012 to58 1Over 16.0 to more58 to more 0D165408312.1.1 All pertinent information regarding the conduct ofeach corrosion test, as prescribed i
48、n the specifications for eachtest,12.1.2 Methods of scribing, shearing, or forming, or com-bination thereof, or test specimens.12.1.3 Method of removal of loose coating.12.1.4 Rust creepage.12.1.5 If applicable, the extent of the removal of loose paintaround scribe that did not extend down to the su
49、bstrate, notingwhich coat(s) were removed.13. Precision and Bias13.1 PrecisionSince this is a method of evaluation basedon measurements after various tests, the statement of precisionapplicable to each specific method of exposure to corrosiveenvironments applies.14. Keywords14.1 blistering; corrosion; creepage; edge/scribe; paints/related coatings/materials; rust; undercuttingASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of t
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