ASTM C695-21

Standard Test Method for Compressive Strength of Carbon and Graphite

SIGNIFICANCE AND USE
4.1 Carbon and graphite can usually support higher loads in compression than in any other mode of stress. This test, therefore, provides a measure of the maximum load-bearing capability of carbon and graphite objects.
SCOPE
1.1 This test method covers the determination of the compressive strength of carbon and graphite at room temperature.  
1.2 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.  
1.3 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.  
1.4 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-2021
• ICS: 71.060.10 - Chemical elements
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.F0 - Manufactured Carbon and Graphite Products

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: C695 − 21
Standard Test Method for
1
Compressive Strength of Carbon and Graphite
This standard is issued under the fixed designation C695; 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* 3.1.1 compressive strength, n—property of solid material
that indicates its ability to withstand a uniaxial compressive
1.1 This test method covers the determination of the com-
load.
pressive strength of carbon and graphite at room temperature.
1.2 The values stated in inch-pound units are to be regarded
4. Significance and Use
as standard. The values given in parentheses are mathematical
4.1 Carbon and graphite can usually support higher loads in
conversions to SI units that are provided for information only
compression than in any other mode of stress. This test,
and are not considered standard.
therefore, provides a measure of the maximum load-bearing
1.3 This standard does not purport to address all of the
capability of carbon and graphite objects.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 5. Apparatus
priate safety, health, and environmental practices and deter-
5.1 Test Machine, conforming to Practice E4 and to the
mine the applicability of regulatory limitations prior to use.
requirementsforspeedoftestingprescribedinSection8ofthis
1.4 This international standard was developed in accor-
test method.
dance with internationally recognized principles on standard-
5.2 Spherical Bearing Blocks attached to the upper or lower
ization established in the Decision on Principles for the
head of the machine in such a manner that the spherical
Development of International Standards, Guides and Recom-
surfaces are in full contact when not loaded. The center of
mendations issued by the World Trade Organization Technical
curvative of the spherical surface shall lie on the surface that
Barriers to Trade (TBT) Committee.
contacts the specimen and on the machine axis. The spherical
surfaces shall be well-lubricated. The radius of the spherical
2. Referenced Documents
surface shall be equal to or greater than the radius of the test
2
2.1 ASTM Standards:
specimen.
D7775 Guide for Measurements on Small Graphite Speci-
5.3 Steel Contact Blocks may be used above or below the
mens
specimen, or both, to protect fixture and test machine surfaces
E4 Practices for Force Verification of Testing Machines
from damage, as illustrated in Fig. 1 and Fig. 2. Contact block
E177 Practice for Use of the Terms Precision and Bias in
surfaces shall be plane and parallel to within 0.0005 in./in.
ASTM Test Methods
(0.0005 mm/mm).
E691 Practice for Conducting an Interlaboratory Study to
Determine the Precision of a Test Method 5.4 All load-bearing machine and fixture surfaces shall have
a minimum hardness of 45 HRC and surface finish of 16 µin.
3. Terminology (0.4 µm) rms maximum. Surfaces in contact with the specimen
shall be flat to less than 0.0005 in./in. (0.0005 mm/mm).
3.1 Definitions:
5.5 Examples of arrangements of the load train are shown
schematically in Fig. 1 and Fig. 2.
1
This test method is under the jurisdiction of ASTM Committee D02 on
6. Sampling
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
Subcommittee D02.F0 on Manufactured Carbon and Graphite Products.
6.1 Samples may be taken from locations and orientations
Current edition approved May 1, 2021. Published May 2021. Originally
that satisfy the objectives of the test.
approved in 1971. Last previous edition approved in 2020 as C695 – 15 (2020).
DOI: 10.1520/C0695-21.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 7. Test Specimen
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
7.1 The test specimen shall be a right cylinder with ends
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. machined to yield planar and parallel faces. These faces shall
*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 ----------------------
C695 − 21
FIG. 1 Elements of Compressive Strength Load Train
FIG. 2 Compressive Test Arrangement with Spherical Blocks on Bottom
ge
...

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: C695 − 15 (Reapproved 2020) C695 − 21
Standard Test Method for
1
Compressive Strength of Carbon and Graphite
This standard is issued under the fixed designation C695; 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 Scope*
1.1 This test method covers the determination of the compressive strength of carbon and graphite at room temperature.
1.2 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.
1.3 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.
1.4 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:
D7775 Guide for Measurements on Small Graphite Specimens
E4 Practices for Force Verification of Testing Machines
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 compressive strength, n—property of solid material that indicates its ability to withstand a uniaxial compressive load.
4. Significance and Use
4.1 Carbon and graphite can usually support higher loads in compression than in any other mode of stress. This test, therefore,
provides a measure of the maximum load-bearing capability of carbon and graphite objects.
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.F0 on Manufactured Carbon and Graphite Products.
Current edition approved May 1, 2020May 1, 2021. Published June 2020May 2021. Originally approved in 1971. Last previous edition approved in 20152020 as
C695 – 15.C695 – 15 (2020). DOI: 10.1520/C0695-15R20.10.1520/C0695-21.
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

---------------------- Page: 1 ----------------------
C695 − 21
5. Apparatus
5.1 Test Machine, conforming to Practice E4 and to the requirements for speed of testing prescribed in Section 8 of this test
method.
5.2 Spherical Bearing Blocks attached to the upper or lower head of the machine in such a manner that the spherical surfaces are
in full contact when not loaded. The center of curvative of the spherical surface shall lie on the surface that contacts the specimen
and on the machine axis. The spherical surfaces shall be well-lubricated. The radius of the spherical surface shall be equal to or
greater than the radius of the test specimen.
5.3 Steel Contact Blocks may be used above or below the specimen, or both, to protect fixture and test machine surfaces from
damage, as illustrated in Fig. 1 and Fig. 2. Contact block surfaces shall be plane and parallel to within 0.0005 in./in. (0.0005
mm/mm).
5.4 All load-bearing machine and fixture surfaces shall have a minimum hardness of 45 HRC and surface finish of 16 μin. (0.4
μm) rms maximum. Surfaces in contact with the specimen shall be flat to less than 0.0005 in./in. (0.0005 mm/mm).
5.5 Examples of arrangements of the load train are shown schematically in Fig. 1 and Fig. 2.
6. Sampling
6.1 Samples may be taken from locations and orientations that satisfy the objectives of the test.
7. Test Specimen
7.1 The test specimen shall be a rig
...