ASTM D6641/D6641M-16e1

Standard Test Method for Compressive Properties of Polymer Matrix Composite Materials Using a Combined Loading Compression (CLC) Test Fixture

SIGNIFICANCE AND USE
5.1 This test method is designed to produce compressive property data for material specifications, research and development, quality assurance, and structural design and analysis. When tabbed (Procedure B) specimens, typically unidirectional composites, are tested, the CLC test method (combined shear end loading) has similarities to Test Methods D3410/D3410M (shear loading) and D695 (end loading). When testing lower strength materials such that untabbed CLC specimens can be used (Procedure A), the benefits of combined loading become particularly prominent. It may not be possible to successfully test untabbed specimens of these same materials using either of the other two methods. When specific laminates are tested (primarily of the [90/0]ns family, although other laminates containing at least one 0° ply can be used), the CLC data are frequently used to “back out” 0° ply strength, using lamination theory to calculate a 0° unidirectional lamina strength  (1, 2). Factors that influence the compressive response include: type of material, methods of material preparation and lay-up, specimen stacking sequence, specimen preparation, specimen conditioning, environment of testing, speed of testing, time at temperature, void content, and volume percent reinforcement. Composite properties in the test direction that may be obtained from this test method include:  
5.1.1 Ultimate compressive strength,  
5.1.2 Ultimate compressive strain,  
5.1.3 Compressive (linear or chord) modulus of elasticity, and  
5.1.4 Poisson's ratio in compression.
SCOPE
1.1 This test method determines the compressive strength and stiffness properties of polymer matrix composite materials using a combined loading compression (CLC) (1)2 test fixture. This test method is applicable to general composites that are balanced and symmetric. The specimen may be untabbed (Procedure A) or tabbed (Procedure B), as required. One requirement for a successful test is that the specimen ends do not crush during the test. Untabbed specimens are usually suitable for use with materials of low orthotropy, for example, fabrics, chopped fiber composites, and laminates with a maximum of 50 % 0° plies, or equivalent (see 6.4). Materials of higher orthotropy, including unidirectional composites, typically require tabs.  
1.2 The compressive force is introduced into the specimen by combined end- and shear-loading. In comparison, Test Method D3410/D3410M is a pure shear-loading compression test method and Test Method D695 is a pure end-loading test method.  
1.3 Unidirectional (0° ply orientation) composites as well as multi-directional composite laminates, fabric composites, chopped fiber composites, and similar materials can be tested.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the test the inch-pound units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
Note 1: Additional procedures for determining the compressive properties of polymer matrix composites may be found in Test Methods D3410/D3410M, D5467/D5467M, and D695.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Oct-2016
• ICS: 83.140.10 - Films and sheets
• Technical Committee: D30 - Composite Materials
• Drafting Committee: D30.04 - Lamina and Laminate Test Methods

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
´1
Designation: D6641/D6641M − 16
Standard Test Method for
Compressive Properties of Polymer Matrix Composite
Materials Using a Combined Loading Compression (CLC)
1
Test Fixture
This standard is issued under the fixed designation D6641/D6641M; 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
ε NOTE—A label in Figure 3 was corrected editorially in March 2017.
erties of polymer matrix composites may be found in Test Methods
1. Scope
D3410/D3410M, D5467/D5467M, and D695.
1.1 This test method determines the compressive strength
1.5 This standard does not purport to address all of the
and stiffness properties of polymer matrix composite materials
safety concerns, if any, associated with its use. It is the
2
using a combined loading compression (CLC) (1) test fixture.
responsibility of the user of this standard to establish appro-
This test method is applicable to general composites that are
priate safety and health practices and determine the applica-
balanced and symmetric. The specimen may be untabbed
bility of regulatory limitations prior to use.
(Procedure A) or tabbed (Procedure B), as required. One
requirement for a successful test is that the specimen ends do
2. Referenced Documents
not crush during the test. Untabbed specimens are usually
3
2.1 ASTM Standards:
suitable for use with materials of low orthotropy, for example,
D695 Test Method for Compressive Properties of Rigid
fabrics, chopped fiber composites, and laminates with a maxi-
Plastics
mum of 50 % 0° plies, or equivalent (see 6.4). Materials of
D883 Terminology Relating to Plastics
higher orthotropy, including unidirectional composites, typi-
D3410/D3410M Test Method for Compressive Properties of
cally require tabs.
Polymer Matrix Composite Materials with Unsupported
1.2 The compressive force is introduced into the specimen
Gage Section by Shear Loading
by combined end- and shear-loading. In comparison, Test
D3878 Terminology for Composite Materials
Method D3410/D3410M is a pure shear-loading compression
D5229/D5229M TestMethodforMoistureAbsorptionProp-
test method and Test Method D695 is a pure end-loading test
erties and Equilibrium Conditioning of Polymer Matrix
method.
Composite Materials
1.3 Unidirectional(0°plyorientation)compositesaswellas
D5379/D5379M Test Method for Shear Properties of Com-
multi-directional composite laminates, fabric composites,
posite Materials by the V-Notched Beam Method
chopped fiber composites, and similar materials can be tested.
D5467/D5467M Test Method for Compressive Properties of
Unidirectional Polymer Matrix Composite Materials Us-
1.4 The values stated in either SI units or inch-pound units
ing a Sandwich Beam
are to be regarded separately as standard. Within the test the
D5687/D5687M Guide for Preparation of Flat Composite
inch-pound units are shown in brackets. The values stated in
Panels with Processing Guidelines for Specimen Prepara-
each system are not exact equivalents; therefore, each system
tion
must be used independently of the other. Combining values
E4 Practices for Force Verification of Testing Machines
from the two systems may result in nonconformance with the
E6 Terminology Relating to Methods of Mechanical Testing
standard.
E122 Practice for Calculating Sample Size to Estimate,With
NOTE 1—Additional procedures for determining the compressive prop-
Specified Precision, the Average for a Characteristic of a
Lot or Process
1
E132 Test Method for Poisson’s Ratio at Room Temperature
This test method is under the jurisdiction of ASTM Committee D30 on
Composite Materials and is the direct responsibility of Subcommittee D30.04 on
Lamina and Laminate Test Methods.
Current edition approved Nov. 1, 2016. Published November 2016. Originally
3
approved in 2001. Last previous edition approved in 2014 as D6641/D6641M-14. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
DOI: 10.1520/D6641_D6641M-16E01. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
2
Boldface numbers in parentheses refer to the list of references at the end of this Standards volume information, refer to the standard’s Document Summary page on
test method. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
´1
D6641/D6641M − 16
FIG. 1 Photograph of a Typical Combined Loading Compression (CLC) Test Fixture
cr
E177 Practice for Use of the Terms Precision and Bias in F —Euler buckling stress
ASTM Test Methods
G —through-thickness shear modulus of la
...

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: D6641/D6641M − 16 D6641/D6641M − 16
Standard Test Method for
Compressive Properties of Polymer Matrix Composite
Materials Using a Combined Loading Compression (CLC)
1
Test Fixture
This standard is issued under the fixed designation D6641/D6641M; 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
ε NOTE—A label in Figure 3 was corrected editorially in March 2017.
1. Scope
1.1 This test method determines the compressive strength and stiffness properties of polymer matrix composite materials using
2
a combined loading compression (CLC) (1) test fixture. This test method is applicable to general composites that are balanced
and symmetric. The specimen may be untabbed (Procedure A) or tabbed (Procedure B), as required. One requirement for a
successful test is that the specimen ends do not crush during the test. Untabbed specimens are usually suitable for use with
materials of low orthotropy, for example, fabrics, chopped fiber composites, and laminates with a maximum of 50 % 0° plies, or
equivalent (see 6.4). Materials of higher orthotropy, including unidirectional composites, typically require tabs.
1.2 The compressive force is introduced into the specimen by combined end- and shear-loading. In comparison, Test Method
D3410/D3410M is a pure shear-loading compression test method and Test Method D695 is a pure end-loading test method.
1.3 Unidirectional (0° ply orientation) composites as well as multi-directional composite laminates, fabric composites, chopped
fiber composites, and similar materials can be tested.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the test the
inch-pound units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must
be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.
NOTE 1—Additional procedures for determining the compressive properties of polymer matrix composites may be found in Test Methods
D3410/D3410M, D5467/D5467M, and D695.
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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
3
2.1 ASTM Standards:
D695 Test Method for Compressive Properties of Rigid Plastics
D883 Terminology Relating to Plastics
D3410/D3410M Test Method for Compressive Properties of Polymer Matrix Composite Materials with Unsupported Gage
Section by Shear Loading
D3878 Terminology for Composite Materials
D5229/D5229M Test Method for Moisture Absorption Properties and Equilibrium Conditioning of Polymer Matrix Composite
Materials
D5379/D5379M Test Method for Shear Properties of Composite Materials by the V-Notched Beam Method
D5467/D5467M Test Method for Compressive Properties of Unidirectional Polymer Matrix Composite Materials Using a
Sandwich Beam
1
This test method is under the jurisdiction of ASTM Committee D30 on Composite Materials and is the direct responsibility of Subcommittee D30.04 on Lamina and
Laminate Test Methods.
Current edition approved Nov. 1, 2016. Published November 2016. Originally approved in 2001. Last previous edition approved in 2014 as D6641/D6641M-14. DOI:
10.1520/D6641_D6641M-16.10.1520/D6641_D6641M-16E01.
2
Boldface numbers in parentheses refer to the list of references at the end of this test method.
3
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
´1
D6641/D6641M − 16
FIG. 1 Photograph of a Typical Combined Loading Compression (CLC) Test Fixture
D5687/D5687M Guide for Preparation of Flat Composite Panels with Processing Guidelines for Specimen Preparation
E4 Practices for Force Verification of Testing Machines
E6 Terminology Relating to Methods of Mechanical Testing
E122 Practice for
...