Designation:D4145−10(Reapproved2018)StandardTestMethodforCoatingFlexibilityofPrepaintedSheet1ThisstandardisissuedunderthefixeddesignationD4145;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethoddescribesaprocedurefordeterminingtheflexibilityandadhesionoforganiccoatings(paints)onmetallicsubstratesthataredeformedbybendingwhenthesheetisfabricatedintobuildingpanelsorotherproducts.1.2Themetalsubstratemustbecapableofpassingthistestwithoutfracturingandwithnoexcessivegraindevelopment.1.3Thevaluesstatedininch-poundunitsaretoberegardedasstandard.ThevaluesgiveninparenthesesaremathematicalconversionstoSIunitsthatareprovidedforinformationonlyandarenotconsideredstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.Terminology2.1DefinitionsofTermsSpecifictoThisStandard:2.1.1T-bend,n—adescriptionoftheseverityofabendintermsofthegaugeorthickness(t)ofthesheettowhichthecoatinghasbeenapplied;asusedinthistestmethod,theT-bendratingistheminimumnumberofthicknessesofmetalaroundwhichthecoatedsheetisbent(Fig.1),orifbentaroundadie,thenumberofthicknessesofmetalequivalenttothediameterofthedietoachievenofractureorremovalofthecoating.3.SummaryofTestMethod3.1Prepaintedpanelsarebent180°aroundprogressivelymorethicknessesofmetalorlargerdiameterdies,theendpointbeingwhenfailuresnolon...
