ASTM D170909 英文版.docx

ASTM D170909 英文版.docx

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ASTMD170909英文版

Designation:

D1709–09

StandardTestMethodsfor

ImpactResistanceofPlasticFilmbytheFree-FallingDart

Method1

ThisstandardisissuedunderthefixeddesignationD1709;thenumberimmediatelyfollowingthedesignationindicatestheyearof

originaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.A

superscriptepsilon（´）indicatesaneditorialchangesincethelastrevisionorreapproval.

ThisstandardhasbeenapprovedforusebyagenciesoftheDepartmentofDefense.

1.Scope*

1.1Thesetestmethodscoverthedeterminationofthe

energythatcausesplasticfilmtofailunderspecifiedconditions

ofimpactofafree-fallingdart.Thisenergyisexpressedin

termsoftheweight（mass）ofthemissilefallingfroma

specifiedheightwhichwouldresultin50%failureofspeci-

menstested.

1.2Twotestmethodsaredescribed:

NOTE1—Testsonmaterialsthatdonotbreak,foranyreason,arenot

consideredtobevalid.Ithasbeennotedthatcertainmaterialsmaystretch

sofarastobottomoutatthebaseofcertaintestinstrumentswithout

actuallyrupturing.SubcommitteeD20.19iscurrentlyconsideringmeth-

odsfortestingthesematerials.AnyoneinterestedinparticipatinginaTask

GroupshouldcontacttheChairmanofSubcommitteeD20.19through

ASTMInternationalHeadquarters.

1.5Thisstandarddoesnotpurporttoaddressthesafety

concerns,ifany,associatedwithitsuse.Itistheresponsibility

1.2.1TestMethodA

employsadartwitha

oftheuserofthisstandardtoestablishappropriatesafetyand

38.1060.13-mm（1.50060.005-in.）diameterhemispherical

headdroppedfromaheightof0.6660.01m（26.060.4in.）.

Thistestmethodmaybeusedforfilmswhoseimpactresis-

tancesrequiremassesofabout50gorlesstoabout2kgto

fracturethem.

1.2.2TestMethodBemploysadartwitha

50.8060.13-mm（2.00060.005-in.）diameterhemispherical

headdroppedfromaheightof1.5060.03m（60.0+0.25,

−1.70in.）.Itsrangeofapplicabilityisfromabout0.3kgto

about2kg.

1.3Twotestingtechniquesaredescribed:

1.3.1Thestandardtechniqueisthestaircasemethod.By

thistechnique,auniformmissileweightincrementisemployed

duringtestandthemissileweightisdecreasedorincreasedby

theuniformincrementaftertestofeachspecimen,depending

upontheresult（failornotfail）observedforthespecimen.

1.3.2Thealternativetechniqueprovidesfortestingspeci-

mensinsuccessivegroupsoften.Onemissileweightis

employedforeachgroupandmissileweightisvariedin

uniformincrementsfromgrouptogroup.

1.3.3Thestaircasetechniqueandthealternativetechnique

giveequivalentresultsbothastothevaluesofimpactfailure

weightwhichareobtainedandastotheprecisionswithwhich

theyaredetermined.

1.4ThevaluesstatedinSIunitsaretoberegardedas

standard.Thevaluesstatedinparenthesesareforinformation

only.

healthpracticesanddeterminetheapplicabilityofregulatory

limitationspriortouse.

NOTE2—Filmhasbeenarbitrarilydefinedassheetinghavingnominal

thicknessnotgreaterthan0.25µm（0.010in.）.

NOTE3—ThistestmethodistechnicallyequivalenttoISO7765-1:

1988,withtheexceptionofalargertoleranceonthedropheightinTest

MethodB.Also,theISOmethoddoesnotallowthealternativetesting

techniquedescribedinSection11ofthistestmethod.

2.ReferencedDocuments

2.1ASTMStandards:

2

D618PracticeforConditioningPlasticsforTesting

D883TerminologyRelatingtoPlastics

D1248SpecificationforPolyethylenePlasticsExtrusion

MaterialsforWireandCable

D3420TestMethodforPendulumImpactResistanceof

PlasticFilm

D4272TestMethodforTotalEnergyImpactofPlastic

FilmsByDartDrop

D6988GuideforDeterminationofThicknessofPlastic

FilmTestSpecimens

E177PracticeforUseoftheTermsPrecisionandBiasin

ASTMTestMethods

E691PracticeforConductinganInterlaboratoryStudyto

DeterminethePrecisionofaTestMethod

1

ThesetestmethodsareunderthejurisdictionofASTMCommitteeD20on

PlasticsandarethedirectresponsibilityofSubcommitteeD20.19onFilmand

2

ForreferencedASTMstandards,visittheASTMwebsite,www.astm.org,or

Sheeting.

CurrenteditionapprovedMay1,2009.PublishedJune2009.Originally

approvedin1959.Lastpreviouseditionapprovedin2008asD1709–08.

contactASTMCustomerServiceat****************.ForAnnualBookofASTM

Standardsvolumeinformation,refertothestandard’sDocumentSummarypageon

theASTMwebsite.

*ASummaryofChangessectionappearsattheendofthisstandard.

Copyright©ASTMInternational,100BarrHarborDrive,POBoxC700,WestConshohocken,PA19428-2959,UnitedStates.

1

D1709–09

2.2ISOStandard:

ISO7765:

1988PlasticFilmandSheeting—Determination

ofImpactResistancebytheFreeFallingDartMethod—

Part1:

StaircaseMethod3

initiatedenergy,whileTestMethodD4272isinitiationplus

completionenergy.Somefilmsmayshowconsistencywhen

theinitiationenergyisthesameasthetotalenergy.This

statementandthetestdataalsoappearinthesignificance

sectionsandappendixesofTestMethodsD3420andD4272.

3.Terminology

3.1

Definitions—Fordefinitionsrelatedtoplastics,see

5.Apparatus

TerminologyD883.

3.2DefinitionsofTermsSpecifictoThisStandard:

3.2.1failure—anybreakthroughthefilmthatcanbeob-

servedreadilybyfeelingorbyviewingthespecimenunder

backlightedcondition.

3.2.2impactfailureweight—thatmissileweight,estimated

statistically,atwhich50%ofthespecimenswouldfailinthe

specifiedtest.

3.2.3missileweight—theweight（mass）ofthedartplusthe

totalvalueofincrementalweightsattachedplusthelocking

collar.

4.SignificanceandUse

4.1TestMethodsAandBareusedtoestablishtheweightof

thedartwhen50%ofthespecimensfailundertheconditions

specified.Dataobtainedbyonetestmethodcannotbecom-

pareddirectlywiththeothertestmethodnorwiththose

obtainedfromtestsemployingdifferentconditionsofmissile

velocity,impingingsurfacediameter,effectivespecimendiam-

eter,andthickness.Thevaluesobtainedbythesetestvariables

arehighlydependentonthemethodoffilmfabrication.

4.2TheresultsobtainedbyTestMethodsAandBare

greatlyinfluencedbythequalityoffilmundertest.The

confidencelimitsofdataobtainedbythisprocedurecan,

therefore,varysignificantly,dependingonthesamplequality,

uniformityoffilmgage,diemarks,contaminants,etc.（see

Section15）.

4.3TestMethodsAandBhavebeenfoundusefulfor

specificationpurposes.Correlationbetweentestresultsand

fieldperformancecanusuallybeestablished.

4.4Theimpactresistanceofplasticfilm,whilepartly

dependentonthickness,hasnosimplecorrelationwithsample

thickness.Hence,impactvaluescannotbenormalizedovera

rangeofthicknesswithoutproducingmisleadingdataastothe

actualimpactresistanceofthematerial.Datafromthesetest

methodsarecomparableonlyforspecimensthatvarybyno

morethan625%fromthenominaloraveragethicknessofthe

specimenstested.

4.5Severalimpacttestmethodsareusedforfilm.Itis

sometimesdesirabletoknowtherelationshipsamongtest

resultsderivedbydifferenttestmethods.Astudywascon-

ductedinwhichfourfilmsmadefromtworesins（polypropy-

leneandlinearlow-densitypolyethylene）,withtwofilm

thicknessesforeachresin,wereimpactedusingTestMethods

D1709（MethodA）,D3420（ProceduresAandB）,and

D4272.ThetestresultsareshownintheAppendix.Differ-

encesinresultsbetweenTestMethodsD1709andD4272may

beexpectedsinceTestMethodsD1709representsfailure

5.1Theapparatusshallbeconstructedessentiallyasshown

inFig.1,usingthefollowingcomponentscommontobothtest

methods:

5.1.1DartWell—Ifthedartimpactmachineutilizesan

encloseddartwell,itmustcontainasingleunobstructedvent

withaminimumareaof625mm2（~1in.2）toprovideadequate

venting.

NOTE4—Somedartimpactmachinedesignsutilizeencloseddartwells

thatdonotpermitadequateventingtotheatmosphereduringimpact.Data

haveshownthatthishasasignificanteffectontheobservedimpactvalue,

especiallywithfilmsthatexhibithighelongationduringtesting,resulting

inatypicallyhighimpactvalues.

NOTE5—Theuseofsmaller,multipleventsispermittedifitcanbe

demonstratedthattheventingefficiencyiscomparableandhasno

statisticallysignificanteffectonthevaluesobtained.

5.1.2SpecimenClamp—Atwo-pieceannularspecimen

clamphavinganinsidediameterof12562.0mm（5.0+0.0,

−0.15in.）andconformingtothefollowingrequirements:

5.1.2.1Thelowerorstationaryhalfoftheclampshallbe

mountedrigidlysothattheplaneofthespecimenishorizontal.

5.1.2.2Theupperormovablepartoftheclampshallbe

designedtomaintainpositiveandplanecontactwiththelower

partoftheclampwheninposition.Theclampsshallbe

providedwithsuitablemeansofmaintainingsufficientcontact

toholdthefilmsamplefirmlyinplaceduringthetest.

Pneumaticallyoperatedclampshavebeensuccessfullyem-

ployed.

5.1.2.3Rubber-likegasketsmaybeaffixedtothespecimen

contactsurfacesofbothclampstoprovideacushionwhich

minimizesthicknessvariationeffects.Rubbergasketing

3.061mm（0.125+0.025,−0.04in.）thick,of50to60Shore

Adurometerhardness,12562.0mm（5.00+0.00,−0.15in.）

ininsidediameterand15063.0mm（6.0+0.02,−0.2in.）in

outsidediameterhasbeenfoundsatisfactoryforthispurpose.

5.1.2.4Slippageoffilmsgreaterthan0.10mm（0