1、Designation:D170916a1Standard 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.1NOTEEditorially corrected Fig.1 in April 2017.1.Scop
3、e*1.1 These test methods cover the determination 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 t
4、ested.1.2 Two test methods are described:1.2.1 TestMethodAemploysadartwitha38.10 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 abou
5、t 6 kg tofracture them.1.2.2 TestMethodBemploysadartwitha50.80 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 te
6、chnique is the staircase method.Bythis technique,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 spec
7、i-mens in successive groups of ten.One missile weight 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 obtaine
8、d and as to the precisions with whichthey are determined.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 mate
9、rials may stretchso far as to bottom out at the 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 throughAST
10、M International Headquarters.1.5 This standard does 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.
11、NOTE2Film has been arbitrarily defined as sheeting 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 T
12、est Methods Aand B,and the requirement for a vented dart well in 5.1.1.Also,the ISOmethod does not allow the alternative testing technique described inSection 11 of this test method.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-iz
13、ation established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883
14、Terminology Relating to PlasticsD1248 Specification for Polyethylene Plastics ExtrusionMaterials for Wire and Cable1These 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 edi
15、tion approved May 1,2016.Published May 2016.Originallyapproved in 1959.Last previous edition approved in 2016 as D1709 16.DOI:10.1520/D1709-16AE1.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards vol
16、ume 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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the
