ASTM E831-24

Standard Test Method for Linear Thermal Expansion of Solid Materials by Thermomechanical Analysis

SIGNIFICANCE AND USE
5.1 Coefficients of linear thermal expansion are used, for example, for design purposes and to determine if failure by thermal stress may occur when a solid body composed of two different materials is subjected to temperature variations.  
5.2 This test method is comparable to Test Method D3386 for testing electrical insulation materials, but it covers a more general group of solid materials and it defines test conditions more specifically. This test method uses a smaller specimen and substantially different apparatus than Test Methods E228 and D696.  
5.3 This test method may be used in research, specification acceptance, regulatory compliance, and quality assurance.
SCOPE
1.1 This test method determines the technical coefficient of linear thermal expansion of solid materials using thermomechanical analysis techniques.  
1.2 This test method is applicable to solid materials that exhibit sufficient rigidity over the test temperature range such that the sensing probe does not produce indentation of the specimen.  
1.3 The recommended lower limit of coefficient of linear thermal expansion measured with this test method is 5 μm/(m·°C). The test method may be used at lower (or negative) expansion levels with decreased accuracy and precision (see Section 12).  
1.4 This test method is applicable to the temperature range from −120 °C to 900 °C. The temperature range may be extended depending upon the instrumentation and calibration materials used.  
1.5 SI units are the standard. No other units of measurement are included in this standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
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.

General Information

• Status: Published
• Publication Date: 30-Apr-2024
• ICS: 19.060 - Mechanical testing
• Technical Committee: E37 - Thermal Measurements
• Drafting Committee: E37.10 - Fundamental, Statistical and 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: E831 − 24
Standard Test Method for
Linear Thermal Expansion of Solid Materials by
1
Thermomechanical Analysis
This standard is issued under the fixed designation E831; 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.
1. Scope* 2. Referenced Documents
2
1.1 This test method determines the technical coefficient of 2.1 ASTM Standards:
linear thermal expansion of solid materials using thermome- D696 Test Method for Coefficient of Linear Thermal Expan-
chanical analysis techniques. sion of Plastics Between −30°C and 30°C with a Vitreous
Silica Dilatometer
1.2 This test method is applicable to solid materials that
D3386 Test Method for Coefficient of Linear Thermal Ex-
exhibit sufficient rigidity over the test temperature range such
pansion of Electrical Insulating Materials (Withdrawn
that the sensing probe does not produce indentation of the
3
2005)
specimen.
E228 Test Method for Linear Thermal Expansion of Solid
1.3 The recommended lower limit of coefficient of linear
Materials With a Push-Rod Dilatometer
thermal expansion measured with this test method is 5 μm/
E473 Terminology Relating to Thermal Analysis and Rhe-
(m·°C). The test method may be used at lower (or negative)
ology
expansion levels with decreased accuracy and precision (see
E1142 Terminology Relating to Thermophysical Properties
Section 12).
E1363 Test Method for Temperature Calibration of Thermo-
1.4 This test method is applicable to the temperature range mechanical Analyzers
E2113 Test Method for Length Change Calibration of Ther-
from −120 °C to 900 °C. The temperature range may be
extended depending upon the instrumentation and calibration momechanical Analyzers
E3142 Test Method for Thermal Lag of Thermal Analysis
materials used.
Apparatus
1.5 SI units are the standard. No other units of measurement
are included in this standard.
3. Terminology
1.6 This standard does not purport to address all of the
3.1 Definitions—Thermal analysis terms in Terminologies
safety concerns, if any, associated with its use. It is the
E473 and E1142 shall apply to this test method, including
responsibility of the user of this standard to establish appro-
coeffıcient of linear thermal expansion, thermodilatometry, and
priate safety, health, and environmental practices and deter-
thermomechanical analysis.
mine the applicability of regulatory limitations prior to use.
3.2 Definitions of Terms Specific to This Standard:
1.7 This international standard was developed in accor-
3.2.1 mean coeffıcient of linear thermal expansion, (α ),
m
dance with internationally recognized principles on standard-
n—the change in length, relative to the specimen length at
ization established in the Decision on Principles for the
ambient temperature, accompanying a unit change in tempera-
Development of International Standards, Guides and Recom-
ture identified by the midpoint temperature of the temperature
mendations issued by the World Trade Organization Technical
range of measurement.
Barriers to Trade (TBT) Committee.
1 2
This test method is under the jurisdiction of ASTM Committee E37 on Thermal For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Measurements and is the direct responsibility of Subcommittee E37.10 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Fundamental, Statistical and Mechanical Properties. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved May 1, 2024. Published May 2024. Originally the ASTM website.
3
approved in 1981. Last previous edition approved in 2019 as E831 – 19. DOI: The last approved version of this historical standard is referenced on
10.1520/E0831-24. www.astm.org.
*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
1

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E831 − 24
is used when oxidation in air is a concern. Unless effects of moisture are
4. Summary of Test Method
to be studied, use of dry purge gas is recommended and is essential for
4.1 This test method uses a thermomechanical analyzer or
operation at subambient temperatures.
similar device to determine the linear thermal expansion of
6.1.9 Data Collection Device, to provide a means of
solid materials when subjected to a constant heating rate.
acquiring, storing, and displa
...

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: E831 − 19 E831 − 24
Standard Test Method for
Linear Thermal Expansion of Solid Materials by
1
Thermomechanical Analysis
This standard is issued under the fixed designation E831; 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.
1. Scope Scope*
1.1 This test method determines the technical coefficient of linear thermal expansion of solid materials using thermomechanical
analysis techniques.
1.2 This test method is applicable to solid materials that exhibit sufficient rigidity over the test temperature range such that the
sensing probe does not produce indentation of the specimen.
1.3 The recommended lower limit of coefficient of linear thermal expansion measured with this test method is 5 μm/(m·°C). The
test method may be used at lower (or negative) expansion levels with decreased accuracy and precision (see Section 1112).
1.4 This test method is applicable to the temperature range from −120 °C to 900 °C. The temperature range may be extended
depending upon the instrumentation and calibration materials used.
1.5 The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard.
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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
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:
D696 Test Method for Coefficient of Linear Thermal Expansion of Plastics Between −30°C and 30°C with a Vitreous Silica
Dilatometer
3
D3386 Test Method for Coefficient of Linear Thermal Expansion of Electrical Insulating Materials (Withdrawn 2005)
E228 Test Method for Linear Thermal Expansion of Solid Materials With a Push-Rod Dilatometer
E473 Terminology Relating to Thermal Analysis and Rheology
1
This test method is under the jurisdiction of ASTM Committee E37 on Thermal Measurements and is the direct responsibility of Subcommittee E37.10 on Fundamental,
Statistical and Mechanical Properties.
Current edition approved April 1, 2019May 1, 2024. Published April 2019May 2024. Originally approved in 1981. Last previous edition approved in 20142019 as
E831 – 14.E831 – 19. DOI: 10.1520/E0831-19.10.1520/E0831-24.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
The last approved version of this historical standard is referenced on www.astm.org.
*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
1

---------------------- Page: 1 ----------------------
E831 − 24
E1142 Terminology Relating to Thermophysical Properties
E1363 Test Method for Temperature Calibration of Thermomechanical Analyzers
E2113 Test Method for Length Change Calibration of Thermomechanical Analyzers
E3142 Test Method for Thermal Lag of Thermal Analysis Apparatus
3. Terminology
3.1 Definitions—Thermal analysis terms in Terminologies E473 and E1142 shall apply to this test method, including coeffıcient
of linear thermal expansion, thermodilatometry, and thermomechanical analysis.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 mean coeffıcient of linear thermal expansion, (α ), n—the change in length, relative to the specimen length at ambient
m
temperature, accompanying a unit change in temperature identified by the midpoint temperature of the temperature range of
measurement.
4. Summary of Test Method
4.1 This test method uses a thermomechanical analyzer or similar device to determine the linear thermal expansion of solid
materials when subjected to a constant heating rate.
4.2 The change of the specimen length is electronically rec
...