ASTM D1938-02

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Designation:D1938–02
Standard Test Method for
Tear-Propagation Resistance (Trouser Tear) of Plastic Film
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and Thin Sheeting by a Single-Tear Method
This standard is issued under the fixed designation D 1938; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope * D 4000 Classification System for Specifying Plastic Mate-
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rials
1.1 This test method covers the determination of the force
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E 4 Practices for Load Verification of Testing Machines
necessary to propagate a tear in plastic film and thin sheeting
E 691 Practice for Conducting an Interlaboratory Study to
(thickness of 1 mm (0.04 in.) or less) by a single-tear method.
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Determine the Precision of a Test Method
The method is not applicable for film or sheeting material
2.2 ISO Standard:
where brittle failures occur during testing.
ISO 6383-1 Film and Sheeting—Determination of Tear
NOTE 1—Film has been arbitrarily defined as sheeting having nominal 7
Resistance Part 1 Trouser Tear Method
thickness not greater than 0.25 mm (0.010 in.).
3. Terminology
1.2 Constant-Rate-of-Grip Separation Test —This test
method employs a constant rate of separation of the grips
3.1 Definitions: For definitions of terms used in this test
holding the test specimen.
method, refer to Terminology D 883.
1.2.1 Specimen extension may be measured in this test
4. Summary of Test Method
method by grip separation.
1.3 The values stated in SI units are to be regarded as the
4.1 The force to propagate a tear across a film or sheeting
standard. The values given in parentheses are provided for specimen is measured using a constant-rate-of-grip separation
information only.
machine as described in Test Methods D 882 and is calculated
1.4 This standard does not purport to address all of the from the load-time chart.
safety concerns, if any, associated with its use. It is the
5. Significance and Use
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- 5.1 This test method is of value in rating the tear-
bility of regulatory limitations prior to use. propagationresistanceofvariousplasticfilmsandthinsheeting
of comparable thickness. For highly extensible film or sheeting
NOTE 2—This standard is similar to ISO 6383-1, but is not considered
the deformation energy of the specimen legs is significantly
technicallyequivalent.ThespecimensizeforISO6383-1islarger,andthe
greater than the tearing energy.The tear-propagation resistance
method specifies different test speeds.
in slightly extensible or non-extensible film or sheeting is
2. Referenced Documents
distinguished from the tear-propagation resistance in highly
extensible film or sheeting by the load-time or load-
2.1 ASTM Standards:
displacement data, (Fig. 1 and Fig. 2). The tear-propagation
D 374 Test Methods for Thickness of Solid Electrical Insu-
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force for slightly extensible or non-extensible material is
lation
determined from the average tear force versus the initial and
D 618 Practice for Conditioning Plastics and Electrical
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peak force for a highly extensible material.
Insulating Materials for Testing
5.2 This test method should be used for specification accep-
D 882 Test Methods for Tensile Properties of Thin Plastic
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tance testing only after it has been demonstrated that the data
Sheeting
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for the particular material are acceptably reproducible.
D 883 Terminology Relating to Plastics
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This test method is under the jurisdiction ofASTM Committee D20 on Plastics
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and is the direct responsibility of Subcommittee D20.19 on Film and Sheeting. Annual Book of ASTM Standards, Vol 08.02.
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Current edition approved March 10, 2002. Published May 2002. Originally Annual Book of ASTM Standards, Vol 03.01.
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published as D 1938 – 62 T. Last previous edition D 1938 – 94. Annual Book of ASTM Standards, Vol 14.02.
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Annual Book of ASTM Standards, Vol 10.01. Available from American National Standards Institute, 25 W. 43rd St., 4th
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Annual Book of ASTM Standards, Vol 08.01. Floor, New York, NY 10036.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D1938
6.1.3.2 Self-aligning grips are attached to the fixed and
movable member of the testing machine in such a manner that
they will move freely into alignment as soon as any load is
applied so that the long axis of the test specimen will coincide
with the direction of the applied pull through the center line of
the grip assembly. The specim
...