ASTM C272-01(2007)
(Test Method)Standard Test Method for Water Absorption of Core Materials for Structural Sandwich Constructions
Standard Test Method for Water Absorption of Core Materials for Structural Sandwich Constructions
SIGNIFICANCE AND USE
The moisture content of most core materials is related to such properties as electrical properties (such as dielectric constant, loss tangent, and electrical resistance) and mechanical properties (such as strength and modulus). The amount of weight the structure may gain by the core absorbing water is also important. It should be noted that in a sandwich panel there are facings bonded on two sides of the core that affect the amount of water absorbed by the core.
SCOPE
1.1 This test method covers the determination of the relative amount of water absorption by various types of structural core materials when immersed or in a high relative humidity environment. This test method is intended to apply to only structural core materials; honeycomb, foam, and balsa wood.
1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given may be approximate.
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
Relations
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:C272–01(Reapproved2007)
Standard Test Method for
Water Absorption of Core Materials for Structural Sandwich
Constructions
This standard is issued under the fixed designation C272; 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 Department of Defense.
1. Scope 5. Significance and Use
1.1 This test method covers the determination of the relative 5.1 The moisture content of most core materials is related to
amount of water absorption by various types of structural core such properties as electrical properties (such as dielectric
materials when immersed or in a high relative humidity constant, loss tangent, and electrical resistance) and mechani-
environment. This test method is intended to apply to only cal properties (such as strength and modulus). The amount of
structural core materials; honeycomb, foam, and balsa wood. weight the structure may gain by the core absorbing water is
1.2 The values stated in SI units are to be regarded as the also important. It should be noted that in a sandwich panel
standard. The inch-pound units given may be approximate. there are facings bonded on two sides of the core that affect the
1.3 This standard does not purport to address all of the amount of water absorbed by the core.
safety concerns, if any, associated with its use. It is the
6. Interferences
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- 6.1 Material and Specimen Preparation—Cracks in the
specimen and rough surfaces can increase the apparent water
bility of regulatory limitations prior to use.
absorption.
2. Referenced Documents
6.2 Surface Water—Some core materials tend to collect
2.1 ASTM Standards: water on the surfaces or trap water in corners, and, if not
C271/C271M Test Method for Density of Sandwich Core removed will give incorrect results.
Materials
7. Apparatus
C274 Terminology of Structural Sandwich Constructions
D1193 Specification for Reagent Water 7.1 Analytical Balance, capable of measurement to 0.001 g.
7.2 Circulating Air Oven, capable of maintaining uniform
3. Terminology
temperatures with an accuracy of 63°C (65°F).
3.1 Definitions—Terminology C274 defines terms relating 7.3 Humidity Chamber, capable of maintaining uniform
to sandwich constructions. relative humidity with an accuracy of 65 % and a uniform
temperature with an accuracy of 63°C (65°F).
4. Summary of Test Method
7.4 The water used in this test method shall be distilled
4.1 A small piece of the core material is conditioned in water (Specification D1193, Type IV reagent water) or deion-
various moisture conditions, and the amount of moisture
ized water.
absorbed is measured by the weight increase in the specimen.
8. Sampling and Test Specimens
8.1 Test at least five specimens per test condition unless
This test method is under the jurisdiction of ASTM Committee D30 on valid results can be gained through the use of fewer specimens,
Composite Materials and is the direct responsibility of Subcommittee D30.09 on
such as in the case of a designed experiment.
Sandwich Construction.
8.2 The test specimen shall be 75 by 75 by 12.7 mm (3 by
Current edition approved Jan. 1, 2007. Published January 2007. Originally
3by0.5in.)thick.Thethicknessofthespecimenshallbeinthe
approved in 1951. Last previous edition approved in 2001 as C272 – 01. DOI:
10.1520/C0272-01R07.
same direction as the core thickness when used in a sandwich
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
panel.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
8.3 Machine, saw, or shear the test specimens from the core
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. sample so as to have smooth surfaces that are free from cracks.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
C272–01 (2007)
8.4 Measure the length and width dimensions to the nearest from the chamber, shake vigorously, wipe off all surface water
0.25 mm (0.01 in.) and the thickness to the nearest 0.025 mm with a dry cloth (if required), dip the specimen in alcohol,
(0.001 in.). shake vigorously, allow the alcohol to evaporate, and immedi-
ately weigh and record the weight.
9. Calibration
11.3 Test Method C—Maximum Percent Weight Gain—
9.1 The accuracy of all measuring equipment shall have
Completely immerse the specimens in a container of water at
certified calibrations that are current at the time of use of the
a temperature of 23 6 3°C (73 6 5°F). Materials that float
equipment.
should be held under water by a loose net. At the end of 48 h,
remove the specimens one at a time, shake vigorously, wipe off
10. Conditioning
all surface water with a dry cloth (if required), dip the
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.