ASTM D6745-22

Standard Test Method for Linear Thermal Expansion of Electrode Carbons

SIGNIFICANCE AND USE
5.1 Coefficients of linear thermal expansion are used for design and quality control purposes and to determine dimensional changes of parts and components (such as carbon anodes, cathodes, and so forth) when subjected to varying temperatures.
SCOPE
1.1 This test method covers the determination of the coefficient of linear thermal expansion (CTE) for carbon anodes and cathodes used in the aluminum industry, in baked form, by use of a vitreous silica dilatometer.  
1.2 The applicable temperature range for this test method for research purposes is ambient to 1000 °C. The recommended maximum use temperature for product evaluation is 500 °C.  
1.3 This test method and procedure is based on Test Method E228, which is a generic all-encompassing method. Specifics dictated by the nature of electrode carbons and the purposes for which they are used are addressed by this procedure.  
1.4 Electrode carbons in the baked form will only exhibit primarily reversible dimensional changes when heated.  
1.5 The values stated in SI units are to be regarded as 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-2022
• ICS: 19.060 - Mechanical testing
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.05 - Properties of Fuels, Petroleum Coke and Carbon Material

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: D6745 − 22
Standard Test Method for
1
Linear Thermal Expansion of Electrode Carbons
This standard is issued under the fixed designation D6745; 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.
1. Scope* E228Test Method for Linear Thermal Expansion of Solid
Materials With a Push-Rod Dilatometer
1.1 This test method covers the determination of the coef-
E691Practice for Conducting an Interlaboratory Study to
ficient of linear thermal expansion (CTE) for carbon anodes
Determine the Precision of a Test Method
andcathodesusedinthealuminumindustry,inbakedform,by
use of a vitreous silica dilatometer.
3. Terminology
1.2 The applicable temperature range for this test method
3.1 Definitions:
for research purposes is ambient to 1000°C. The recom-
mended maximum use temperature for product evaluation is
3.1.1 linear thermal expansion, n—the change in length per
500°C. unit length resulting from a temperature change. Linear ther-
malexpansionissymbolicallyrepresentedby∆L/L ,where∆L
0
1.3 ThistestmethodandprocedureisbasedonTestMethod
isthelengthchangeofthespecimen(L −L ), L and L arethe
1 0 0 1
E228, which is a generic all-encompassing method. Specifics
specimens lengths at reference temperature T and test tem-
dictatedbythenatureofelectrodecarbonsandthepurposesfor 0
perature T , respectively. Linear thermal expansion is often
which they are used are addressed by this procedure. 1
expressedasapercentageorinpartspermillion(suchasµm/m
1.4 Electrode carbons in the baked form will only exhibit
–6
or 10 m/m).
primarily reversible dimensional changes when heated.
3.1.1.1 mean coeffıcient of linear thermal expansion (CTE),
1.5 The values stated in SI units are to be regarded as
n—The linear thermal expansion per change in temperature;
standard. No other units of measurement are included in this
the mean coefficient of linear thermal expansion is represented
standard.
by:
1.6 This standard does not purport to address all of the
∆L/L 1 ∆L 1 L 2 L
safety concerns, if any, associated with its use. It is the 0 1 0
α¯ 5 5 · 5 (1)
T
1
∆T L ∆T L T 2 T
responsibility of the user of this standard to establish appro- 0 0 1 0
The coefficient of thermal expansion is expressed in parts
priate safety, health, and environmental practices and deter-
–6
per million per degree Kelvin (such as µm/mK or 10
mine the applicability of regulatory limitations prior to use.
m/mK).
1.7 This international standard was developed in accor-
3.1.1.1 Discussion—This has to be accompanied by the
dance with internationally recognized principles on standard-
values of the two temperatures to be meaningful; the reference
ization established in the Decision on Principles for the
temperature (T ) is 20°C, and the notation may then only
0
Development of International Standards, Guides and Recom-
contain a single number, such as α¯ , meaning the mean
200
mendations issued by the World Trade Organization Technical
coefficient of linear thermal expansion between 20°C and
Barriers to Trade (TBT) Committee.
200°C.
2. Referenced Documents
3.2 Definitions of Terms Specific to This Standard:
2
2.1 ASTM Standards: 3.2.1 reference specimen, n—a particularly identified or
pedigreed material sample, with well-characterized behavior
and independently documented performance.
1
This test method is under the jurisdiction of ASTM Committee D02 on
3.2.2 specimen, n—a representative piece of a larger body
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
SubcommitteeD02.05onPropertiesofFuels,PetroleumCokeandCarbonMaterial. (anode, cathode, and so forth) that is considered to be fairly
Current edition approved May 1, 2022. Published June 2022. Originally
typical of a portion or of the entire piece.
approved in 2001. Last previous edition approved in 2015 as D6745–11 (2015).
DOI: 10.1520/D6745-22.
3.2.3 vitreous silica dilatometer, n—a device used to deter-
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
mine linear thermal expansion, by measuring the difference in
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
linear thermal expansion between a test specimen and the
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. vitreous silica parts of the dilatometer.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, W
...

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: D6745 − 11 (Reapproved 2015) D6745 − 22
Standard Test Method for
1
Linear Thermal Expansion of Electrode Carbons
This standard is issued under the fixed designation D6745; 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 covers the determination of the coefficient of linear thermal expansion (CTE) for carbon anodes and cathodes
used in the aluminum industry, in baked form, by use of a vitreous silica dilatometer.
1.2 The applicable temperature range for this test method for research purposes is ambient to 1000 °C. The recommended
maximum use temperature for product evaluation is 500 °C.
1.3 This test method and procedure is based on Test Method E228, which is a generic all-encompassing method. Specifics dictated
by the nature of electrode carbons and the purposes for which they are used are addressed by this procedure.
1.4 Electrode carbons in the baked form will only exhibit primarily reversible dimensional changes when heated.
1.5 The values stated in SI units are to be regarded as 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 safety, health, and healthenvironmental 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:
E228 Test Method for Linear Thermal Expansion of Solid Materials With a Push-Rod Dilatometer
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 linear thermal expansion, n—the change in length per unit length resulting from a temperature change. Linear thermal
expansion is symbolically represented by ΔL/ΔL/L , where ΔL is the length change of the specimen (L −L ), L and L are the
0 1 0 0 1
1
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.05 on Properties of Fuels, Petroleum Coke and Carbon Material.
Current edition approved Oct. 1, 2015May 1, 2022. Published December 2015June 2022. Originally approved in 2001. Last previous edition approved in 20112015 as
D6745 – 11.D6745 – 11 (2015). DOI: 10.1520/D6745-11R15.10.1520/D6745-22.
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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D6745 − 22
specimens lengths at reference temperature T and test temperature T , respectively. Linear thermal expansion is often expressed
0 1
–6
as a percentage or in parts per million (such as μm/m). μm/m or 10 m/m).
3.1.1.1 mean coeffıcient of linear thermal expansion (CTE), n—The linear thermal expansion per change in temperature; the
mean coefficient of linear thermal expansion is represented by:
ΔL/L 1 ΔL 1 L 2 L
0 1 0
¯
α 5 5 · 5 (1)
T
1
ΔT L ΔT L T 2 T
0 0 1 0
–6
The coefficient of thermal expansion is expressed in parts per million per degree Kelvin (such as μm/mK or 10 m/mK).
3.1.1.1 Discussion—
This has to be accompanied by the values of the two temperatures to be meaningful; the reference temperature (T ) is 20 °C, and
0
the notation may then only contain a single number, such as α¯ , meaning the mean coefficient of linear thermal expansion
200
between 20 °C and 200 °C.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 reference specimen, n—a particularly identified or pedigreed material sample, with well-characterized behavior and
indep
...