ASTM_D_4242_-_07_2013.pdf

Designation:D424207(Reapproved 2013)Standard Test Method forInclined Plate Flow for Thermosetting Coating Powders1This standard is issued under the fixed designation D4242;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 test method specifies a method for determining theflow characteristics of a fused thermosetting coating powderdown a plane inclined at a set angle to the horizontal.The testgives an indication of the degree of melt flow that may occurduring the curing of the coating powder.This characteristiccontributes to the coherence of the coating,to its surfaceappearance and to the degree of coverage over sharp edges(seeTest Method D2967),however,it should not be used as the solefactor for judgment.The test acts as a useful method forchecking for batch to batch variation in the behavior of a givencoating powder.Correlation between the results from coatingpowders of differing composition is not to be expected.Thismethod is unlikely to yield meaningful results with coatingpowders which have gel times of less than one minute at thetest temperature(see Test Method D4217).Oven drafts,angleof inclination and pellet variations significantly affect resultsmaking inter-lab reproducibility somewhat difficult to corre-late.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 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 to determine theapplicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD2967 Test Method for Corner Coverage of Powder Coat-ingsD4217 Test Method for Gel Time of Thermosetting CoatingPowderD5965 Test Methods for Specific Gravity of Coating Pow-ders2.2 Other Documents:ISO 8130-2 Coating powdersPart 2:Determination ofdensity by gas comparison pyknometer3ISO 8130-3 Coating powdersPart 3:Determination ofdensity by liquid displacement pyknometer3ISO 813011:1997 Coating powdersPart 11:Inclined-plane flow test33.Terminology3.1 Definitions:3.1.1 coating powder,nfinely divided particles of resin,either thermoplastic or thermosetting,generally incorporatingpigments,fillers,and additives and remaining finely dividedduring storage under suitable conditions,which after fusingand possibly curing,give a continuous film.3.1.2 powder coating,ncoatings which are protective ordecorative,or both,formed by the application of a coatingpowder to a substrate and fused in a continuous film by theapplication of heat or radiant energy.3.1.3 gel time of a coating powder,nthe interval requiredat a given temperature for a coating powder to be transformedfrom a dry solid to a gel-like state.3.1.4 cure time of a coating powder,nthe time required fora thermosetting coating powder to sufficiently chemicallycrosslink at a given temperature to provide the required coatingproperties.3.1.5 thermosetting,adjdescribing a material that,whenheated per a minimum recommended cure condition,under-goes a chemical reaction and a permanent change to a moredurable state capable of specific properties as designed forsubstrate protection or decoration,or both.4.Summary of Test Method4.1 The thermosetting coating powder is pressed into apellet of standard size which is allowed to melt and flow downa heated inclined plate.The extent of flow is measured.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.51 on Powder Coatings.Current edition approved June 1,2013.Published July 2013.Originally approvedin 1983.Last previous edition approved in 2007 as D4242 07.DOI:10.1520/D4242-07R13.2For 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.3Available from International Organization for Standardization(ISO),1 rue deVaremb,Case postale 56,CH-1211,Geneva 20,Switzerland,http:/www.iso.ch.*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 5.Significance and Use5.1 This test method is useful for selecting coating powdersof similar characteristics of melt flow under minimal shear.Itis not recommended as an absolute measurement,but rather asa comparative measurement of samples on the same panelmeasured at the same time.6.A