ASTM D6790/D6790M-16

Standard Test Method for Determining Poisson's Ratio of Honeycomb Cores

SIGNIFICANCE AND USE
5.1 Certain sandwich panel analyses require the Poisson's ratio of the honeycomb core. It is not possible to measure the honeycomb's Poisson's ratio by conventional methods.  
5.2 This test method provides a standard method of determining the Poisson’s ratio of honeycomb core materials for design properties, material specifications, research and development applications, and quality assurance.  
5.3 Factors that influence the Poisson’s ratio of honeycomb core materials and shall therefore be reported include the following: core material, methods of material fabrication, core geometry, core thickness, core thickness uniformity, cell wall thickness, specimen geometry, specimen preparation, and specimen conditioning.
SCOPE
1.1 This test method covers the determination of the sandwich honeycomb core Poisson's ratio from the anticlastic curvature radii, see Fig. 1.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.2.1 Within the text, the inch-pound units are shown in brackets.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Mar-2016
• ICS: 49.025.99 - Other materials
• Technical Committee: D30 - Composite Materials
• Drafting Committee: D30.09 - Sandwich Construction

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
Designation: D6790/D6790M − 16
Standard Test Method for
1
Determining Poisson’s Ratio of Honeycomb Cores
This standard is issued under the fixed designation D6790/D6790M; 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 3. Terminology
1.1 This test method covers the determination of the sand- 3.1 Definitions—Terminology D3878 defines terms relating
wich honeycomb core Poisson’s ratio from the anticlastic to high-modulus fibers and their composites, as well as terms
curvature radii, see Fig. 1.
relating to sandwich constructions. Terminology D883 defines
termsrelatingtoplastics.TerminologyE456andPracticeE177
1.2 The values stated in either SI units or inch-pound units
define terms relating to statistics. In the event of a conflict
are to be regarded separately as standard. The values stated in
between terms, Terminology D3878 shall have precedence
each system may not be exact equivalents; therefore, each
over the other terminologies.
system shall be used independently of the other. Combining
values from the two systems may result in non-conformance 3.2 Symbols: c = chord measurement
with the standard.
CV = coefficient of variation statistic of a sample population
1.2.1 Within the text, the inch-pound units are shown in for a given property (in percent)
brackets.
d = depth measurement
R = anticlastic curvature radius
a
1.3 This standard does not purport to address all of the
R = cylinder radius
safety concerns, if any, associated with its use. It is the c
S = standard deviation statistic of a sample population for
responsibility of the user of this standard to establish appro- n-1
a given property
priate safety and health practices and determine the applica-
x = test result for an individual specimen from the sample
bility of regulatory limitations prior to use. 1
population for a given property
x¯ = mean or average (estimate of mean) of a sample popu-
2. Referenced Documents
lation for a given property
2
2.1 ASTM Standards:
v = Poisson’s ratio
C271/C271M Test Method for Density of Sandwich Core
Materials
4. Summary of Test Method
D883 Terminology Relating to Plastics
D3878 Terminology for Composite Materials 4.1 This test method determines the Poisson’s ratio of
sandwich honeycomb core by bending the core around a
D5229/D5229M Test Method for MoistureAbsorption Prop-
erties and Equilibrium Conditioning of Polymer Matrix cylinder and taking measurements of the anticlastic curvature
that occurs.
Composite Materials
E122 Practice for Calculating Sample Size to Estimate,With
Specified Precision, the Average for a Characteristic of a 5. Significance and Use
Lot or Process
5.1 Certain sandwich panel analyses require the Poisson’s
E177 Practice for Use of the Terms Precision and Bias in
ratio of the honeycomb core. It is not possible to measure the
ASTM Test Methods
honeycomb’s Poisson’s ratio by conventional methods.
E456 Terminology Relating to Quality and Statistics
5.2 This test method provides a standard method of deter-
mining the Poisson’s ratio of honeycomb core materials for
design properties, material specifications, research and devel-
1
This test method is under the jurisdiction of ASTM Committee D30 on
opment applications, and quality assurance.
Composite Materials and is the direct responsibility of Subcommittee D30.09 on
Sandwich Construction.
5.3 Factors that influence the Poisson’s ratio of honeycomb
Current edition approved April 1, 2016. Published April 2016. Originally
core materials and shall therefore be reported include the
approved in 2002. Last previous edition approved in 2014 as D6790 - 14. DOI:
10.1520/D6790_D6790M-16.
following: core material, methods of material fabrication, core
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
geometry, core thickness, core thickness uniformity, cell wall
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
thickness, specimen geometry, specimen preparation, and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. specimen conditioning.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D6790/D6790M − 16
within 0.5 % of the sample length, width and thickness. For
typical specimen geometries, an instrument with an accuracy
of 60.025 mm [60.001 in.] is desirable for thickness
measurement, whereas an instrument with an accuracy of
60.25 mm [60.01 in.] is desirable for length and width
measurement.
7.2 Cylinders—Acylinder shall be utili
...

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: D6790/D6790M − 14 D6790/D6790M − 16
Standard Test Method for
1
Determining Poisson’s Ratio of Honeycomb Cores
This standard is issued under the fixed designation D6790/D6790M; 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
1.1 This test method covers the determination of the sandwich honeycomb core Poisson’s ratio from the anticlastic curvature
radii, see Fig. 1.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.2.1 Within the text, the inch-pound units are shown in brackets.
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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
C271/C271M Test Method for Density of Sandwich Core Materials
3
C274 Terminology of Structural Sandwich Constructions (Withdrawn 2016)
D883 Terminology Relating to Plastics
D3878 Terminology for Composite Materials
D5229/D5229M Test Method for Moisture Absorption Properties and Equilibrium Conditioning of Polymer Matrix Composite
Materials
E122 Practice for Calculating Sample Size to Estimate, With Specified Precision, the Average for a Characteristic of a Lot or
Process
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E456 Terminology Relating to Quality and Statistics
3
E1309 Guide for Identification of Fiber-Reinforced Polymer-Matrix Composite Materials in Databases (Withdrawn 2015)
3
E1434 Guide for Recording Mechanical Test Data of Fiber-Reinforced Composite Materials in Databases (Withdrawn 2015)
3. Terminology
3.1 Definitions—Terminology D3878 defines terms relating to high-modulus fibers and their composites.
Terminologycomposites, as C274 defineswell as terms relating to structural sandwich constructions. Terminology D883 defines
terms relating to plastics. Terminology E456 and Practice E177 define terms relating to statistics. In the event of a conflict between
terms, Terminology D3878 shall have precedence over the other terminologies.
3.2 Symbols: c = chord measurement
CV = coefficient of variation statistic of a sample population for a given property (in percent)
d = depth measurement
R = anticlastic curvature radius
a
R = cylinder radius
c
S = standard deviation statistic of a sample population for a given property
n-1
1
This test method is under the jurisdiction of ASTM Committee D30 on Composite Materials and is the direct responsibility of Subcommittee D30.09 on Sandwich
Construction.
Current edition approved May 1, 2014April 1, 2016. Published June 2014April 2016. Originally approved in 2002. Last previous edition approved in 20072014 as
D6790 - 02D6790 - 14.(2007). DOI: 10.1520/D6790_D6790M-14.10.1520/D6790_D6790M-16.
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D6790/D6790M − 16
FIG. 1 Anticlastic Curvature
x = test result for an individual specimen from the sample population for a given property
1
x¯ = mean or average (estimate of mean) of a sample population for a given property
v = Poisson’s ratio
4. Summary of Test Method
4.1 This test method determines the Poisson’s ratio of sandwich honeycomb core by bending the core around a cylinder and
taking measurements of the anticlastic curvature that occurs.
5. Significance and Use
5.1 Certain sandwich panel analyses require the Poisson’s ratio of the honeycomb core. It is not possible to measure the
honeycomb’s Poisson’s ratio by conventional methods.
5.2 This test method provides a standard method of determining the Poisson’s ratio of honeycomb core materials for design
properties, mat
...