1、Designation:D170915aStandard Test Methods forImpact Resistance of Plastic Film by the Free-Falling DartMethod1This standard is issued under the fixed designation D1709;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last
2、revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 These test methods cover the determination
3、 of theenergy that causes plastic film to fail under specified conditionsof impact of a free-falling dart.This energy is expressed interms of the weight(mass)of the missile falling from aspecified height which would result in 50%failure of speci-mens tested.1.2 Two test methods are described:1.2.1 T
4、estMethodAemploysadartwitha38.10 6 0.13-mm(1.500 6 0.005-in.)diameter hemisphericalhead dropped from a height of 0.66 6 0.01 m(26.0 6 0.4 in.).This test method can be used for films whose impact resis-tances require masses of about 50 g or less to about 6 kg tofracture them.1.2.2 TestMethodBemploysa
5、dartwitha50.80 6 0.13-mm(2.000 6 0.005-in.)diameter hemisphericalhead dropped from a height of 1.52 6 0.03 m(60.0+0.25,1.70 in.).Its range of applicability is from about 0.3 kg toabout 6 kg.1.3 Two testing techniques are described:1.3.1 The standard technique is the staircase method.Bythis technique
6、,the missile weight employed during the test isdecreased or increased by uniform increments after the testingof each specimen,depending upon the result(fail or not fail)observed for the specimen.1.3.2 The alternative technique provides for testing speci-mens in successive groups of ten.One missile w
7、eight isemployed for each group and the missile weight is varied inuniform increments from group to group.1.3.3 The staircase technique and the alternative techniquegive equivalent results both as to the values of impact failureweight which are obtained and as to the precisions with whichthey are de
8、termined.1.4 The values stated in SI units are to be regarded asstandard.The values stated in parentheses are for informationonly.NOTE1Tests on materials that do not break,for any reason,are notconsidered to be valid.It has been noted that certain materials may stretchso far as to bottom out at the
9、base of certain test instruments withoutactually rupturing.Subcommittee D20.19 is currently considering meth-ods for testing these materials.Anyone interested in participating in a TaskGroup should contact the Chairman of Subcommittee D20.19 throughASTM International Headquarters.1.5 This standard d
10、oes not purport to address the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety andhealth practices and determine the applicability of regulatorylimitations prior to use.NOTE2Film has been arbitrarily defined as sheeti
11、ng having nominalthickness not greater than 0.25 mm(0.010 in.).NOTE3This test method is technically equivalent to ISO 7765-1:1988,with the exception of a larger tolerance on the drop height in TestMethod B,smaller tolerances on the dart diameters for Test Methods Aand B,and the requirement for a ven
12、ted dart well in 5.1.1.Also,the ISOmethod does not allow the alternative testing technique described inSection 11 of this test method.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD1248 Specification for Polyethylene
13、 Plastics ExtrusionMaterials for Wire and CableD3420 Test Method for Pendulum Impact Resistance ofPlastic FilmD4272 Test Method for Total Energy Impact of Plastic FilmsBy Dart DropD6988 Guide for Determination of Thickness of Plastic FilmTest SpecimensE177 Practice for Use of the Terms Precision and
14、 Bias inASTM Test Methods1These test methods are under the jurisdiction of ASTM Committee D20 onPlastics and are the direct responsibility of Subcommittee D20.19 on Film,Sheeting,and Molded Products.Current edition approved May 15,2015.Published June 2015.Originallyapproved in 1959.Last previous edi
15、tion approved in 2015 as D1709 15.DOI:10.1520/D1709-15A.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
16、 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 E691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 ISO Standard:ISO 7765:1988 Plastic Film and SheetingDeterminationof Impact Resistance by the Free Falling Dart MethodPart 1:Staircase Method33.Terminology3.1 DefinitionsFor definitions related to plastics,see Ter-minology D883.3.2 Defi
