ASTM D638-08

Standard Test Method for Tensile Properties of Plastics

SIGNIFICANCE AND USE
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. For many materials, there may be a specification that requires 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 D 4000 lists the ASTM materials standards that currently exist.
Tensile properties may vary with specimen preparation and with speed and environment of testing. Consequently, where precise comparative results are desired, these factors must be carefully controlled.
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, the greatest care must be exercised 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 must be taken to secure the maximum degree of uniformity in details of preparation, treatment, and handling.
Tensile properties may 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 condit...
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 can be used 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, Test Methods D 882 is the preferred test method. Materials with a thickness greater than 14 mm (0.55 in.) must be reduced by machining.
1.3 This test method includes the option of determining Poisson's ratio at room temperature.
Note 1—This test method and ISO 527-1 are technically equivalent.  
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 D 229 and Test Method D 651.
Note 4—For tensile properties of...

General Information

• Status: Historical
• Publication Date: 31-Mar-2008
• ICS: 83.080.01 - Plastics in general
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.10 - Mechanical Properties

Relations

• Replaced By: ASTM D638-10 - Standard Test Method for Tensile Properties of Plastics
• Effective Date: 15-May-2010

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information.
Designation:D638–08
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 Department of Defense.
1. Scope* 1.5 The values stated in SI units are to be regarded as
standard. The values given in parentheses are for information
1.1 This test method covers the determination of the tensile
only.
properties of unreinforced and reinforced plastics in the form
1.6 This standard does not purport to address all of the
of standard dumbbell-shaped test specimens when tested under
safety concerns, if any, associated with its use. It is the
defined conditions of pretreatment, temperature, humidity, and
responsibility of the user of this standard to establish appro-
testing machine speed.
priate safety and health practices and determine the applica-
1.2 This test method can be used for testing materials of any
bility of regulatory limitations prior to use.
thickness up to 14 mm (0.55 in.). However, for testing
specimens in the form of thin sheeting, including film less than
2. Referenced Documents
1.0 mm (0.04 in.) in thickness, Test Methods D882 is the
2
2.1 ASTM Standards:
preferred test method. Materials with a thickness greater than
D229 Test Methods for Rigid Sheet and Plate Materials
14 mm (0.55 in.) must be reduced by machining.
Used for Electrical Insulation
1.3 This test method includes the option of determining
D412 Test Methods for Vulcanized Rubber and Thermo-
Poisson’s ratio at room temperature.
plastic Elastomers—Tension
NOTE 1—This test method and ISO 527-1 are technically equivalent.
D618 Practice for Conditioning Plastics for Testing
NOTE 2—This test method is not intended to cover precise physical
D651 Method of Test for Tensile Strength of Molded
procedures. It is recognized that the constant rate of crosshead movement
3
Electrical Insulating Material
type of test leaves much to be desired from a theoretical standpoint, that
D882 Test Method for Tensile Properties of Thin Plastic
wide differences may exist between rate of crosshead movement and rate
Sheeting
of strain between gage marks on the specimen, and that the testing speeds
specified disguise important effects characteristic of materials in the
D883 Terminology Relating to Plastics
plastic state. Further, it is realized that variations in the thicknesses of test
D1822 Test Method for Tensile-Impact Energy to Break
specimens,whicharepermittedbytheseprocedures,producevariationsin
Plastics and Electrical Insulating Materials
thesurface-volumeratiosofsuchspecimens,andthatthesevariationsmay
D3039/D3039M Test Method for Tensile Properties of
influence the test results. Hence, where directly comparable results are
Polymer Matrix Composite Materials
desired, all samples should be of equal thickness. Special additional tests
D4000 Classification System for Specifying Plastic Materi-
should be used where more precise physical data are needed.
NOTE 3—This test method may be used for testing phenolic molded als
resin or laminated materials. However, where these materials are used as
D4066 Classification System for Nylon Injection and Ex-
electrical insulation, such materials should be tested in accordance with
trusion Materials (PA)
Test Methods D229 and Test Method D651.
D5947 Test Methods for Physical Dimensions of Solid
NOTE 4—For tensile properties of resin-matrix composites reinforced
Plastics Specimens
with oriented continuous or discontinuous high modulus >20-GPa
6
E4 Practices for Force Verification of Testing Machines
[>3.0 3 10 -psi) fibers, tests shall be made in accordance with Test
E83 Practice for Verification and Classification of Exten-
Method D3039/D3039M.
someter Systems
1.4 Test data obtained by this test method are relevant and
E132 Test Method for Poisson’s Ratio at Room Tempera-
appropriate for use in engineering design.
ture
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 volume information, refer to the standard’s Document Summary page on
Current edition approved April 1, 2008. Published May 2008. Originally the ASTM website.
3
approved in 1941. Last previous edition approved in 2003 as D638 - 03. DOI: Withdrawn. The last approved version of this historical standard is referenced
10.1520/D0638-08. on ww
...

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:D638–03 Designation:D638–08
Standard Test Method for
1
Tensile Properties of Plastics
This standard is issued under the fixed designation D 638; 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 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 can be used for testing materials of any thickness up to 14 mm [0.55 in.].(0.55 in.). However, for testing
specimens in the form of thin sheeting, including film less than 1.0 mm [0.04 in.](0.04 in.) in thickness, Test Methods D 882 is
the preferred test method. Materials with a thickness greater than 14 mm [0.55 in.](0.55 in.) must be reduced by machining.
1.3 This test method includes the option of determining Poisson’s ratio at room temperature.
NOTE 1—This test method and ISO 527-1 are technically equivalent.
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
betweengagemarksonthespecimen,andthatthetestingspeedsspecifieddisguiseimportanteffectscharacteristicofmaterialsintheplasticstate.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 D 229 and Test Method D 651.
NOTE 4—For tensile properties of resin-matrix composites reinforced with oriented continuous or discontinuous high modulus >20-GPa [>3.0 3 10
6-psi]-psi) fibers, tests shall be made in accordance with Test Method D 3039/D 3039M.
1.4 Test data obtained by this test method are relevant and appropriate for use in engineering design.
1.5 The values stated in SI units are to be regarded as the standard. The values given in bracketsparentheses 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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D 229 Test Methods for Rigid Sheet and Plate Materials Used for Electrical Insulation
D 412 Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension
D 618 Practice for Conditioning Plastics for Testing
D 651Test Method for Tensile Strength of Molded Electrical Insulating Materials Method of Test for Tensile Strength of
3
Molded Electrical Insulating Material
D 882 Test MethodsMethod for Tensile Properties of Thin Plastic Sheeting
D 883 Terminology Relating to Plastics
D 1822 Test Method for Tensile-Impact Energy to Break Plastics and Electrical Insulating Materials
D 3039/D 3039M Test Method for Tensile Properties of Polymer Matrix Composite Materials
D 4000 Classification System for Specifying Plastic Materials
D 4066 Classification System for Nylon Injection and Extrusion Materials (PA)
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 DecemberApril 1, 2003.2008. Published January 2004.May 2008. Originally approved in 1941. Last previous edition approved in 20022003 as
D638-02a.D 638 - 03.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of
...