ASTM_D_7087_-_05a_2010.pdf

Designation:D708705a(Reapproved 2010)Standard Test Method forAn Imaging Technique to Measure Rust Creepage at Scribeon Coated Test Panels Subjected to CorrosiveEnvironments1This standard is issued under the fixed designation D7087;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,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.1.Scope1.1 This test method covers the measurement of rust creep-age area from a scribe line on painted/coated flat test panelsafter exposure to corrosive environments.This test method hasthe advantage of simplicity and ease of use.Expensive equip-ment is not required,and the results are more accurate thanvisual evaluation but not as precise as advanced digitalimaging.1.2 This test method uses visual imaging software to deter-mine the area damaged by rust creepage from the scribe.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.4 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 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:2B117 Practice for Operating Salt Spray(Fog)ApparatusD1014 Practice for Conducting Exterior Exposure Tests ofPaints and Coatings on Metal SubstratesD1654 Test Method for Evaluation of Painted or CoatedSpecimens Subjected to Corrosive EnvironmentsD4585 Practice for Testing Water Resistance of CoatingsUsing Controlled CondensationD4587 Practice for Fluorescent UV-Condensation Expo-sures of Paint and Related CoatingsD5894 Practice for Cyclic Salt Fog/UV Exposure of PaintedMetal,(Alternating Exposures in a Fog/Dry Cabinet and aUV/Condensation Cabinet)D6695 Practice for Xenon-Arc Exposures of Paint andRelated CoatingsG85 Practice for Modified Salt Spray(Fog)Testing3.Significance and Use3.1 This test method provides a means of evaluating andcomparing development of corrosion at scribe on painted/coated flat test panels after exposure to corrosive environ-ments.4.Apparatus4.1 Transparent Plastic SheetUse transparent plastic sheetwith thickness approximately 0.085 mm(0.0034 in.or 3.4 mil).The sheet material must be transparent enough for easy tracingand must be sufficiently absorbent to provide good ink adhe-sion.34.2 Tracing PenA black permanent marker with ultrafinetip approximately 0.5 mm(0.02 in.)in diameter.4.3 RulerAny transparent ruler with 1-mm black divi-sions.This length shall be shorter than either length or width ofglass surface of scanner.4.4 Computer and Scanning SystemAny computer andcompatible scanning system is applicable.A computer with atleast 32 MB of RAM is recommended.4Aflat bed scanner with1200 dpi optical,12002400 dpi hardware resolution is sug-gested.The scanner must have a feature where it selects thebest possible resolution required for scanning.There is no needto calibrate or change settings while scanning.4.5 Image SoftwareUse any image software capable ofreading an image file generated from the computer andscanning system,calibrating length,and integrating area rap-idly and accurately.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 June 1,2010.Published July 2010.Originally approvedin 2005.Last previous edition approved in 2005 as D7087 05A.DOI:10.1520/D7087-05AR10.2For 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.3The transparent plastic sheet material of one-gallon size zipper freezer bagwithout surface texture was found acceptable in round robin testing.4A PC compatible computer with the Windows 95,Windows 98,Windows ME,Windows NT,Windows 2000 or Windows XP operating system is applicable.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Specimen Scribing5.1 Scribe test specimens in accordance with Test MethodD1654,section on Preliminary Treatment of Test Specimens.The panels should be scribed in a single straight line.6.Exposure of Test Specimens6.1 Prior to exposure,measure the width of the scribe.Record this information.6.2 Expose test specimens in accordance with any of thefollowing Practices B117,D1014,D4585,D4587,D5894,D6695,and G85,or any other applicable test method,as agreedupon between the producer and the user.The exposure cycle,length of test and evaluation intervals shall be agreed uponprior to exposure of specimens