ASTM D638-22

Standard Test Method for Tensile Properties of Plastics

SIGNIFICANCE AND USE
4.1 This test method is designed to produce tensile property data for the control and specification of plastic materials. These data are also useful for qualitative characterization and for research and development.  
4.2 Some material specifications that require the use of this test method, but with some procedural modifications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that material specification before using this test method. Table 1 in Classification D4000 lists the ASTM materials standards that currently exist.  
4.3 Tensile properties are known to vary with specimen preparation and with speed and environment of testing. Consequently, where precise comparative results are desired, these factors must be carefully controlled.  
4.4 It is realized that a material cannot be tested without also testing the method of preparation of that material. Hence, when comparative tests of materials per se are desired, exercise great care to ensure that all samples are prepared in exactly the same way, unless the test is to include the effects of sample preparation. Similarly, for referee purposes or comparisons within any given series of specimens, care shall be taken to secure the maximum degree of uniformity in details of preparation, treatment, and handling.  
4.5 Tensile properties provide useful data for plastics engineering design purposes. However, because of the high degree of sensitivity exhibited by many plastics to rate of straining and environmental conditions, data obtained by this test method cannot be considered valid for applications involving load-time scales or environments widely different from those of this test method. In cases of such dissimilarity, no reliable estimation of the limit of usefulness can be made for most plastics. This sensitivity to rate of straining and environment necessitates testing over a broad load-time scale (including impact and creep) and range of environmental conditions i...
SCOPE
1.1 This test method covers the determination of the tensile properties of unreinforced and reinforced plastics in the form of standard dumbbell-shaped test specimens when tested under defined conditions of pretreatment, temperature, humidity, and testing machine speed.  
1.2 This test method is applicable for testing materials of any thickness up to 14 mm (0.55 in.). However, for testing specimens in the form of thin sheeting, including film less than 1.0 mm (0.04 in.) in thickness, ASTM standard D882 is the preferred test method. Materials with a thickness greater than 14 mm (0.55 in.) shall be reduced by machining.  
1.3 This test method includes the option of determining Poisson's ratio at room temperature.
Note 1: This standard and ISO 527-1 address the same subject matter, but differ in technical content.
Note 2: This test method is not intended to cover precise physical procedures. It is recognized that the constant rate of crosshead movement type of test leaves much to be desired from a theoretical standpoint, that wide differences may exist between rate of crosshead movement and rate of strain between gage marks on the specimen, and that the testing speeds specified disguise important effects characteristic of materials in the plastic state. Further, it is realized that variations in the thicknesses of test specimens, which are permitted by these procedures, produce variations in the surface-volume ratios of such specimens, and that these variations may influence the test results. Hence, where directly comparable results are desired, all samples should be of equal thickness. Special additional tests should be used where more precise physical data are needed.
Note 3: This test method may be used for testing phenolic molded resin or laminated materials. However, where these materials are used as electrical insulation, such materials should be tested in accordance with Test Methods D229 and Test Method D651...

General Information

• Status: Published
• Publication Date: 30-Jun-2022
• ICS: 83.080.01 - Plastics in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.10 - Mechanical Properties

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D638 − 22
Standard Test Method for
1
Tensile Properties of Plastics
This standard is issued under the fixed designation D638; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript 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* consider the precautions and limitations of this method found
in Note 2 and Section 4 before considering these data for
1.1 This test method covers the determination of the tensile
engineering design.
properties of unreinforced and reinforced plastics in the form
1.5 The values stated in SI units are to be regarded as
ofstandarddumbbell-shapedtestspecimenswhentestedunder
standard. The values given in parentheses are for information
defined conditions of pretreatment, temperature, humidity, and
only.
testing machine speed.
1.6 This standard does not purport to address all of the
1.2 This test method is applicable for testing materials of
safety concerns, if any, associated with its use. It is the
any thickness up to 14 mm (0.55 in.). However, for testing
responsibility of the user of this standard to establish appro-
specimensintheformofthinsheeting,includingfilmlessthan
priate safety, health, and environmental practices and deter-
1.0 mm (0.04 in.) in thickness, ASTM standard D882 is the
mine the applicability of regulatory limitations prior to use.
preferred test method. Materials with a thickness greater than
1.7 This international standard was developed in accor-
14 mm (0.55 in.) shall be reduced by machining.
dance with internationally recognized principles on standard-
1.3 This test method includes the option of determining
ization established in the Decision on Principles for the
Poisson’s ratio at room temperature.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
NOTE 1—This standard and ISO 527-1 address the same subject matter,
but differ in technical content.
Barriers to Trade (TBT) Committee.
NOTE 2—This test method is not intended to cover precise physical
procedures. It is recognized that the constant rate of crosshead movement
2. Referenced Documents
type of test leaves much to be desired from a theoretical standpoint, that
2
2.1 ASTM Standards:
wide differences may exist between rate of crosshead movement and rate
of strain between gage marks on the specimen, and that the testing speeds D229Test Methods for Rigid Sheet and Plate Materials
specified disguise important effects characteristic of materials in the
Used for Electrical Insulation
plastic state. Further, it is realized that variations in the thicknesses of test
D412TestMethodsforVulcanizedRubberandThermoplas-
specimens,whicharepermittedbytheseprocedures,producevariationsin
tic Elastomers—Tension
thesurface-volumeratiosofsuchspecimens,andthatthesevariationsmay
D618Practice for Conditioning Plastics for Testing
influence the test results. Hence, where directly comparable results are
desired, all samples should be of equal thickness. Special additional tests
D651Test Method for Test for Tensile Strength of Molded
3
should be used where more precise physical data are needed.
Electrical Insulating Materials (Withdrawn 1989)
NOTE 3—This test method may be used for testing phenolic molded
D882Test Method for Tensile Properties of Thin Plastic
resin or laminated materials. However, where these materials are used as
Sheeting
electrical insulation, such materials should be tested in accordance with
D883Terminology Relating to Plastics
Test Methods D229 and Test Method D651.
NOTE 4—For tensile properties of resin-matrix composites reinforced D1822Test Method for Determining the Tensile-Impact
with oriented continuous or discontinuous high modulus >20-GPa
Resistance of Plastics
6
(>3.0×10 -psi) fibers, tests shall be made in accordance with Test
D3039/D3039MTest Method forTensile Properties of Poly-
Method D3039/D3039M.
mer Matrix Composite Materials
1.4 Test data obtained by this test method have been found
D4000Classification System for Specifying Plastic Materi-
to be useful in engineering design. However, it is important to
als
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties. Standards
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D638 − 14 D638 − 22
Standard Test Method for
1
Tensile Properties of Plastics
This standard is issued under the fixed designation D638; 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 (´) 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 This test method covers the determination of the tensile properties of unreinforced and reinforced plastics in the form of
standard dumbbell-shaped test specimens when tested under defined conditions of pretreatment, temperature, humidity, and testing
machine speed.
1.2 This test method is applicable for testing materials of any thickness up to 14 mm (0.55 in.). However, for testing specimens
in the form of thin sheeting, including film less than 1.0 mm (0.04 in.) in thickness, ASTM standard D882 is the preferred test
method. Materials with a thickness greater than 14 mm (0.55 in.) shall be reduced by machining.
1.3 This test method includes the option of determining Poisson’s ratio at room temperature.
NOTE 1—This standard and ISO 527-1 address the same subject matter, but differ in technical content.
NOTE 2—This test method is not intended to cover precise physical procedures. It is recognized that the constant rate of crosshead movement type of test
leaves much to be desired from a theoretical standpoint, that wide differences may exist between rate of crosshead movement and rate of strain between
gage marks on the specimen, and that the testing speeds specified disguise important effects characteristic of materials in the plastic state. Further, it is
realized that variations in the thicknesses of test specimens, which are permitted by these procedures, produce variations in the surface-volume ratios of
such specimens, and that these variations may influence the test results. Hence, where directly comparable results are desired, all samples should be of
equal thickness. Special additional tests should be used where more precise physical data are needed.
NOTE 3—This test method may be used for testing phenolic molded resin or laminated materials. However, where these materials are used as electrical
insulation, such materials should be tested in accordance with Test Methods D229 and Test Method D651.
6
NOTE 4—For tensile properties of resin-matrix composites reinforced with oriented continuous or discontinuous high modulus >20-GPa (>3.0 × 10 -psi)
fibers, tests shall be made in accordance with Test Method D3039/D3039M.
1.4 Test data obtained by this test method have been found to be useful in engineering design. However, it is important to consider
the precautions and limitations of this method found in Note 2 and Section 4 before considering these data for engineering design.
1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1
This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.
Current edition approved Dec. 15, 2014July 1, 2022. Published March 2015July 2022. Originally approved in 1941. Last previous edition approved in 20102014 as
D638 - 10.D638 - 14. DOI: 10.1520/D0638-14.10.1520/D0638-22.
*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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D638 − 22
1.7 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2
2.1 ASTM Standards:
D229 Test Methods for Rigid Sheet and Plate Materials Used for Electrical Insulation
D412 Test Methods for Vulcanized Rubber and Thermoplastic Elast
...