ASTM E21-20

Standard Test Methods for Elevated Temperature Tension Tests of Metallic Materials

SIGNIFICANCE AND USE
4.1 The elevated-temperature tension test gives a useful estimate of the ability of metals to withstand the application of applied tensile forces. Using established and conventional relationships it can be used to give some indication of probable behavior under other simple states of stress, such as compression, shear, etc. The ductility values give a comparative measure of the capacity of different materials to deform locally without cracking and thus to accommodate a local stress concentration or overstress; however, quantitative relationships between tensile ductility and the effect of stress concentrations at elevated temperature are not universally valid. A similar comparative relationship exists between tensile ductility and strain-controlled, low-cycle fatigue life under simple states of stress. The results of these tension tests can be considered as only a questionable comparative measure of the strength and ductility for service times of many hours. Therefore, the principal usefulness of the elevated-temperature tension test is to assure that the tested material is similar to reference material when other measures such as chemical composition and microstructure also show the two materials are similar.
SCOPE
1.1 These test methods cover procedure and equipment for the determination of tensile strength, yield strength, elongation, and reduction of area of metallic materials at elevated temperatures.  
1.2 Determination of modulus of elasticity and proportional limit are not included.  
1.3 Tension tests under conditions of rapid heating or rapid strain rates are not included.  
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.  
1.5 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.  
1.6 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: 31-Aug-2020
• ICS: 77.040.10 - Mechanical testing of metals
• Technical Committee: E28 - Mechanical Testing
• Drafting Committee: E28.04 - Uniaxial Testing

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: E21 − 20
Standard Test Methods for
1
Elevated Temperature Tension Tests of Metallic Materials
This standard is issued under the fixed designation E21; 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.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.
1. Scope* E29 Practice for Using Significant Digits in Test Data to
Determine Conformance with Specifications
1.1 These test methods cover procedure and equipment for
E74 Practices for Calibration and Verification for Force-
thedeterminationoftensilestrength,yieldstrength,elongation,
Measuring Instruments
and reduction of area of metallic materials at elevated tempera-
E83 Practice for Verification and Classification of Exten-
tures.
someter Systems
1.2 Determination of modulus of elasticity and proportional
E177 Practice for Use of the Terms Precision and Bias in
limit are not included.
ASTM Test Methods
1.3 Tension tests under conditions of rapid heating or rapid E220 Test Method for Calibration of Thermocouples By
Comparison Techniques
strain rates are not included.
E633 Guide for Use of Thermocouples in Elevated-
1.4 The values stated in inch-pound units are to be regarded
Temperature Mechanical Testing
as standard. The values given in parentheses are mathematical
E691 Practice for Conducting an Interlaboratory Study to
conversions to SI units that are provided for information only
Determine the Precision of a Test Method
and are not considered standard.
1.5 This standard does not purport to address all of the
3. Terminology
safety concerns, if any, associated with its use. It is the
3.1 Definitions of terms relating to tension testing which
responsibility of the user of this standard to establish appro-
appear in Terminology E6, apply to this test method. These
priate safety, health, and environmental practices and deter-
terms include alignment, axial strain, bending strain, gauge
mine the applicability of regulatory limitations prior to use.
length, elongation, elongation after fracture, extensometer
1.6 This international standard was developed in accor-
system, necking, reduction of area, tensile strength, yield
dance with internationally recognized principles on standard-
strength. In addition, the definitions of the following terms
ization established in the Decision on Principles for the
relating to tension testing are included.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical 3.1.1 Definitions of terms relating to tension testing which
appear in E6, shall apply to the terms used in this test method.
Barriers to Trade (TBT) Committee.
3.2 Definitions:
2. Referenced Documents
3.2.1 indicated temperature, n—the temperature indicated
2
2.1 ASTM Standards:
by the temperature-measuring system that meets the require-
E4 Practices for Force Verification of Testing Machines
ments of this standard.
E6 Terminology Relating to Methods of Mechanical Testing
3.2.2 specified temperature—the test temperature requested
E8/E8M Test Methods for Tension Testing of Metallic Ma-
by and reported to the customer.
terials
3.2.3 temperature-measuring system, n—a system consist-
ing of one or more temperature-measuring transducers with the
1 appropriate indicating instruments, extension wires, reference
These test methods are under the jurisdiction of ASTM Committee E28 on
Mechanical Testing and are the direct responsibility of Subcommittee E28.04 on
junctions or ice points, and data acquisition devices.
Uniaxial Testing.
3.2.3.1 Discussion—The temperature-measuring transducer
Current edition approved Sept. 1, 2020. Published October 2020. Originally
ɛ1
is usually a thermocouple.
approved in 1933. Last previous edition approved in 2017 as E21 – 17 . DOI:
10.1520/E0021-20.
3.2.3.2 Discussion—The use of the term measuring system
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
conformstothedefinitionof "measuringsystem”intheJCGM:
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
International Vocabulary of Metrology – Basic and General
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Concepts and Associated terms (VIM).
*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

---------------
...

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.
´1
Designation: E21 − 17 E21 − 20
Standard Test Methods for
1
Elevated Temperature Tension Tests of Metallic Materials
This standard is issued under the fixed designation E21; 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
ε NOTE—Section 3 was editorially updated in April 2019.
1. Scope*
1.1 These test methods cover procedure and equipment for the determination of tensile strength, yield strength, elongation, and
reduction of area of metallic materials at elevated temperatures.
1.2 Determination of modulus of elasticity and proportional limit are not included.
1.3 Tension tests under conditions of rapid heating or rapid strain rates are not included.
1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical
conversions to SI units that are provided for information only and are not considered standard.
1.5 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.
1.6 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:
E4 Practices for Force Verification of Testing Machines
E6 Terminology Relating to Methods of Mechanical Testing
E8/E8M Test Methods for Tension Testing of Metallic Materials
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E74 Practices for Calibration and Verification for Force-Measuring Instruments
E83 Practice for Verification and Classification of Extensometer Systems
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E220 Test Method for Calibration of Thermocouples By Comparison Techniques
1
These test methods are under the jurisdiction of ASTM Committee E28 on Mechanical Testing and are the direct responsibility of Subcommittee E28.04 on Uniaxial
Testing.
Current edition approved Dec. 1, 2017Sept. 1, 2020. Published January 2018October 2020. Originally approved in 1933. Last previous edition approved in 20092017 as
ɛ1
E21 – 09.E21 – 17 . DOI: 10.1520/E0021-17E01.10.1520/E0021-20.
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.
*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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E21 − 20
E633 Guide for Use of Thermocouples in Creep and Stress-Rupture Testing to 1800°F (1000°C) in Air
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions of terms relating to tension testing which appear in Terminology E6, apply to this test method. These terms include
alignment, axial strain, bending strain, gauge length, elongation, elongation after fracture, extensometer system, necking, reduction
of area, tensile strength, yield strength. In addition, the definitions of the following terms relating to tension testing are included.
3.1.1 Definitions of terms relating to tension testing which appear in E6, shall apply to the terms used in this test method.
3.2 Definitions:
3.2.1 reduced section,indicated temperature, n—the central portion of the specimen that has a cross section smaller than the
gripped ends.temperature indicated by the temperature-measuring system that meets the requirements of this standard.
3.2.1.1 Discussion—
The cross section is uniform within prescribed tolerances.
3.2.2 specified temperature—the test temperature requested by and reported to the customer.
3.2.3 length oftemperature-measur
...