ASTM C272-91(1996)

Standard Test Method for Water Absorption of Core Materials for Structural Sandwich Constructions

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

• Status: Historical
• Publication Date: 09-Sep-2001
• ICS: 83.120 - Reinforced plastics
• Technical Committee: D30 - Composite Materials
• Drafting Committee: D30.09 - Sandwich Construction

Relations

• Replaced By: ASTM C272-01 - Standard Test Method for Water Absorption of Core Materials for Structural Sandwich Constructions
• Effective Date: 10-Sep-2001
• Referred By: ASTM C578-22 - Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation
• Effective Date: 10-Sep-2001

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: C 272 – 91 (Reapproved 1996)
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
Water Absorption of Core Materials for Structural Sandwich
Constructions
This standard is issued under the fixed designation C 272; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope temperature with an accuracy of 65°F (63°C).
4.4 The water used in this test method should be distilled
1.1 This test method covers the determination of the relative
water (Specification D 1193, Type IV reagent water) or deion-
rate of water absorption by various types of structural core
ized water.
materials when immersed or in a high relative humidity
environment. This test method is intended to apply to only
5. Test Specimens
structural core materials; honeycomb, foam, and balsa wood.
5.1 The test specimen shall be 3 by 3 by 0.5 in. thick (76.2
1.2 The values stated in inch-pound units are to be regarded
by 76.2 by 12.7 mm thick). The thickness of the specimen shall
as the standard. The SI units given may be approximate.
be in the same direction as the core thickness when used in a
1.3 This standard does not purport to address all of the
sandwich panel.
safety concerns, if any, associated with its use. It is the
5.2 Machine, saw, or shear the test specimens from the core
responsibility of the user of this standard to establish appro-
sample so as to have smooth surfaces that are free from cracks.
priate safety and health practices and determine the applica-
5.3 Measure the length and width dimensions to the nearest
bility of regulatory limitations prior to use.
0.01 in. (0.254 mm) and the thickness to the nearest 0.001 in.
2. Referenced Documents (0.0254 mm).
2.1 ASTM Standards:
6. Conditioning
C 271 Test Method for Density of Sandwich Core Materi-
2 6.1 Weigh five specimens individually and then oven dry as
als
follows:
D 1193 Specification for Reagent Water
6.1.1 For materials whose water absorption value would be
3. Significance and Use affected by temperatures approximately 230°F (110°C), dry the
specimens in an oven for 24 h at 120 6 5°F (49° 6 3°C), cool
3.1 The moisture content of most core materials is related to
in a desiccator to room temperature, remove, immediately
such properties as electrical properties (such as dielectric, loss
weigh and record the weight.
tangent, electrical resistance) and mechanical properties (such
6.1.2 For materials whose water absorption value has been
as strength and modulus). Also important is the amount of
shown not to be affected by temperatures up to 230°F (110°C),
weight the structure may gain by the core absorbing water. It
dry the specimens in an oven for2hat225 6 5°F (107 6 3°C),
should be noted that in a sandwich panel there are facings
cool in a desiccator to room temperature, remove, and imme-
bonded on two sides of the core that effect the amount of water
diately weigh and record the weight.
absorbed by the core.
6.1.3 In the case of a new material the water absorption
4. Apparatus properties of which are not known, condition the specimens in
accordance with 6.1.1 and 6.1.2 until sufficient experience on
4.1 Analytical Balance, capable of measurement to 0.001 g.
the effect of temperature is achieved to indicate the selection of
4.2 Circulating Air Oven, capable of maintaining uniform
the most satisfactory method.
temperatures with an accuracy of 65°F (63°C).
4.3 Humidity Chamber, capable of maintaining uniform
7. Procedure
relative humidity with an accuracy of 65 % and a uniform
7.1 Test Method A—Twenty-Four-Hour Immersion—
Completely immerse the specimens in a container of 73 6 5°F
(23 6 3°C) water. Materials that float should be held under
This test method is under the jurisdiction of ASTM Committee D-30 on
Composite Materials and is the direct responsibility of Subcommittee D30.09 on
water by a loose net. At the end of 24 h, remove the specimens,
Sandwich Construction.
shake vigorously, wipe off all surface water with
...