ASTM_D_5894_-_16.pdf

Designation:D589416Standard Practice forCyclic Salt Fog/UV Exposure of Painted Metal,(AlternatingExposures in a Fog/Dry Cabinet and a UV/CondensationCabinet)1This standard is issued under the fixed designation D5894;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.Scope*1.1 This practice covers basic principles and operatingpractice for cyclic corrosion/UV exposure of paints on metal,using alternating periods of exposure in two different cabinets:a cycling salt fog/dry cabinet,and a fluorescent UV/condensation cabinet.1.2 This practice is limited to the methods of obtaining,measuring,and controlling exposure conditions,and proce-dures.It does not specify specimen preparation nor evaluationof results.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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:2D610 Practice for Evaluating Degree of Rusting on PaintedSteel SurfacesD714 Test Method for Evaluating Degree of Blistering ofPaintsD1654 Test Method for Evaluation of Painted or CoatedSpecimens Subjected to Corrosive EnvironmentsD4587 Practice for Fluorescent UV-Condensation Expo-sures of Paint and Related CoatingsG85 Practice for Modified Salt Spray(Fog)TestingG113 Terminology Relating to Natural and Artificial Weath-ering Tests of Nonmetallic MaterialsG147 Practice for Conditioning and Handling of Nonmetal-lic Materials for Natural and Artificial Weathering TestsG151 Practice for Exposing Nonmetallic Materials inAccel-erated Test Devices that Use Laboratory Light SourcesG154 Practice for Operating Fluorescent Ultraviolet(UV)Lamp Apparatus for Exposure of Nonmetallic Materials3.Terminology3.1 DefinitionsThe definitions given in Terminology G113are applicable to this practice.4.Summary of Practice4.1 The test specimens are exposed to alternating periods ofone week in a fluorescent UV/condensation chamber followedby one week in a cyclic salt fog/dry chamber.The fluorescentUV/condensation cycle is 4-h UV at 0.89 W/(m2 nm)at 340nm at 60C followed by 4-h condensation at 50C,usingUVA-340 lamps.The fog/dry chamber runs a cycle of 1-h fogat ambient temperature and 1-h dry-off at 35C.The fogelectrolyte is a relatively dilute solution,with 0.05%sodiumchloride and 0.35%ammonium sulfate.5.Significance and Use5.1 The outdoor corrosion of painted metals is influenced bymany factors,including:corrosive atmospheres,rain,con-densed dew,UV light,wet/dry cycling,and temperaturecycling.These factors frequently have a synergistic effect onone another.This practice is intended to provide a morerealistic simulation of the interaction of these factors than isfound in traditional tests with continuous exposure to a staticset of corrosive conditions.5.2 Results obtained from this practice can be used tocompare the relative durability of materials subjected to thespecific test cycle used.5.3 No single exposure test can be specified as a completesimulation of actual use conditions in outdoor environments.Results obtained from exposures conducted according to thispractice can be considered as representative of actual outdoor1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved April 1,2016.Published May 2016.Originallyapproved in 1996.Last previous edition approved in 2010 as D5894 10.DOI:10.1520/D5894-16.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 exposures only when the degree of rank correlation has beenestablished for the specific materials being tested.The relativedurability of materials in actual outdoor service can be verydifferent in different locations because of differences in UVradiation,time of wetness,temperature,pollutants,and otherfactors.Therefore,even if results from a specific artificial testcondition are found to be useful for comparing the relativedurability of materials exposed in a particular exteriorenvironment,it cannot be assumed that they will be useful fordetermining relative durability for a different environ