ASTM E756-04

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:E756–04
Standard Test Method for
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Measuring Vibration-Damping Properties of Materials
This standard is issued under the fixed designation E 756; 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 through cyclic deformation of the damping material, primarily
in tension-compression.
1.1 This test method measures the vibration-damping prop-
3.1.2 constrained-layer (shear) damper—a treatment to
erties of materials: the loss factor, h, andYoung’s modulus, E,
control the vibration of a structure by bonding a layer of
ortheshearmodulus, G.Accurateoverafrequencyrangeof50
damping material between the structure’s surface and an
to 5000 Hz and over the useful temperature range of the
additional elastic layer (that is, the constraining layer), whose
material, this method is useful in testing materials that have
relativestiffnessisgreaterthanthatofthedampingmaterial,so
application in structural vibration, building acoustics, and the
that energy is dissipated through cyclic deformation of the
control of audible noise. Such materials include metals, enam-
damping material, primarily in shear.
els, ceramics, rubbers, plastics, reinforced epoxy matrices, and
3.2 Definitions of Terms Specific to This Standard:
woods that can be formed to cantilever beam test specimen
3.2.1 glassy region of a damping material—a temperature
configurations.
region where a damping material is characterized by a rela-
1.2 This standard does not purport to address all the safety
tively high modulus and a loss factor that increases from
concerns, if any, associated with its use. It is the responsibility
extremely low to moderate as temperature increases (see Fig.
of the user of this standard to establish appropriate safety and
1).
health practices and determine the applicability of regulatory
3.2.2 rubbery region of a damping material—a temperature
limitations prior to use.
region where a damping material is characterized by a rela-
2. Referenced Documents tively low modulus and a loss factor that decreases from
2
moderate to low as temperature increases (see Fig. 1).
2.1 ASTM Standard:
3.2.3 transition region of a damping material—a tempera-
E 548 GuideforGeneralCriteriaUsedforEvaluatingLabo-
ture region between the glassy region and the rubbery region
ratory Competence
where a damping material is characterized by the loss factor
2.2 ANSI Standard:
passing through a maximum and the modulus rapidly decreas-
S2.9 Nomenclature for Specifying Damping Properties of
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ing as temperature increases (see Fig. 1).
Materials
3.3 Symbols—The symbols used in the development of the
3. Terminology
equations in this method are as follows (other symbols will be
introduced and defined more conveniently in the text):
3.1 Definitions—Except for the terms listed below, ANSI
S2.9 defines the terms used in this test method.
3.1.1 free-layer (extensional) damper—a treatment to con-
E = Young’s modulus of uniform beam, Pa
trol the vibration of a structural by bonding a layer of damping
h = loss factor of uniform beam, dimensionless
material to the structure’s surface so that energy is dissipated
E = Young’s modulus of damping material, Pa
1
h = loss factor of damping material, dimensionless
1
G = shear modulus of damping material, Pa
1 1
This test method is under the jurisdiction of ASTM Committee E33 on
EnvironmentalAcousticsandisthedirectresponsibilityofSubcommitteeE33.03on
4. Summary of Method
Sound Transmission.
Current edition approved April 1, 2004. Published May 2004. Originally
4.1 The configuration of the cantilever beam test specimen
approved in 1980. Last Previous edition approved in 1998 as E 756–98.
is selected based on the type of damping material to be tested
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
and the damping properties that are desired. Fig. 2 shows four
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on different test specimens used to investigate extensional and
the ASTM website.
shear damping properties of materials over a broad range of
3
Available from America National Standards Institute, 1430 Broadway, New
modulus values.
York, NY 10018.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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E756–04
step process described above but requires two identical base
beams to be tested and the composite beam to be formed using
the sandwich specimen configuration (Fig. 2d).
4.2 O
...