U.S. patent application number 15/729100 was filed with the patent office on 2018-02-01 for laminate including aluminum sheets.
This patent application is currently assigned to Material Sciences Corporation. The applicant listed for this patent is Material Sciences Corporation. Invention is credited to Peter Bortell, Bryan Tullis.
Application Number | 20180029331 15/729100 |
Document ID | / |
Family ID | 53059544 |
Filed Date | 2018-02-01 |
United States Patent
Application |
20180029331 |
Kind Code |
A1 |
Bortell; Peter ; et
al. |
February 1, 2018 |
LAMINATE INCLUDING ALUMINUM SHEETS
Abstract
A laminate structure and method of forming is provided. The
laminate structure includes a first metal sheet having a first
thickness, a second metal sheet having a second thickness, and an
adhesive core having an adhesive thickness. The adhesive core is
disposed between and bonded to the first and second metal sheets.
The first and second metal sheets are made of an aluminum based
material and the adhesive core is made of an adhesive material also
described as a viscoelastic adhesive material. The laminate
structure is configured such that a ratio of the sum of the first
and second thickness to the adhesive thickness is greater than
either to one (8:1). The laminate structure including the
viscoelastic adhesive core is characterized by a composite loss
factor at 1,000 Hertz which is continuously greater than 0.1 within
a temperature range of 25 degrees Celsius to 50 degrees
Celsius.
Inventors: |
Bortell; Peter; (Tecumseh,
MI) ; Tullis; Bryan; (Livonia, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Material Sciences Corporation |
Elk Grove Village |
IL |
US |
|
|
Assignee: |
Material Sciences
Corporation
Elk Grove Village
IL
|
Family ID: |
53059544 |
Appl. No.: |
15/729100 |
Filed: |
October 10, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/US2015/028801 |
May 1, 2015 |
|
|
|
15729100 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B32B 2307/10 20130101;
B32B 2264/107 20130101; B32B 15/043 20130101; B32B 2307/202
20130101; B23K 2101/18 20180801; B32B 2264/105 20130101; B32B
2255/205 20130101; B32B 15/016 20130101; B32B 15/04 20130101; B32B
2264/101 20130101; B32B 37/12 20130101; B32B 37/06 20130101; B32B
2311/24 20130101; B32B 7/12 20130101; B23K 35/0255 20130101; B32B
15/01 20130101; B32B 2255/06 20130101; B32B 15/20 20130101; B32B
2305/30 20130101; B32B 2319/00 20130101 |
International
Class: |
B32B 7/12 20060101
B32B007/12; B32B 15/20 20060101 B32B015/20; B32B 37/12 20060101
B32B037/12; B32B 15/04 20060101 B32B015/04 |
Claims
1. A laminate structure comprising: a first metal sheet having a
first thickness; a second metal sheet having a second thickness;
wherein the first and second metal sheets are made of an aluminum
based material; an adhesive core having an adhesive core thickness;
wherein the adhesive core is disposed between and bonded to the
first and second metal sheets; wherein a ratio of the sum of the
first and second thickness to the adhesive core thickness is
greater than eight to one (8:1); an intermediate layer disposed
between the adhesive layer and a surface of one of the first and
second metal sheets; wherein the intermediate layer passivates the
surface of the one of the first and second metal sheets; and
wherein the intermediate layer includes one of titanium, zirconium,
and tri-chromium oxide.
2. The laminate structure of claim 1, wherein the adhesive core is
made of one of a phenolic modified rubber material, and a polyester
based material; and wherein the laminate structure is characterized
by a composite loss factor at 1,000 Hertz which is continuously
greater than 0.1 within a temperature range of 25 degrees Celsius
to 50 degrees Celsius.
3. The laminate structure of claim 1, wherein: the first thickness
is within a range of 0.4 mm to 2.0 mm; the second thickness is
within a range of 0.4 mm to 2.0 mm; and the adhesive core thickness
is within a range of 0.013 mm to 0.076 mm.
4. The laminate structure of claim 3, wherein the laminate
structure is characterized by one of an n value of 0.1 or greater
and an r value of 0.8 or greater.
5. The laminate structure of claim 3, wherein the laminate
structure is characterized by one of an adhesive strength as
measured by T-peel of at least 1.75 Newtons/millimeter (N/mm), and
a lap shear strength of at least 2 mega-Pascal (MPa).
6. The laminate structure of claim 1, further comprising: an
auxiliary layer disposed between the intermediate layer and the
adhesive core; wherein the auxiliary layer is configured as a
corrosion prevention layer.
7. The laminate structure of claim 1, further comprising: an
isolation layer bonded to one of the first and second metal sheets
such that the isolation layer forms an exterior layer of the
laminate structure.
8. The laminate structure of claim 1, wherein the metal sheets are
made from one of a 5xxx series aluminum alloy and a 6xxx series
aluminum alloy.
9. A laminate structure comprising: a first metal sheet; a second
metal sheet; wherein the first and second metal sheets are made of
an aluminum based material; and an adhesive core disposed between
and bonded to the first and second metal sheets; wherein the
adhesive core is made of one of a phenolic modified rubber
material, and a polyester based material; wherein the laminate
structure is characterized by a composite loss factor at 1,000
Hertz which is continuously greater than 0.1 within a temperature
range of 25 degrees Celsius to 50 degrees Celsius.
10. The laminate structure of claim 9, wherein the laminate
structure is characterized by a composite loss factor which is
continuously greater than 0.1 within a temperature range of 15
degrees Celsius to 70 degrees Celsius.
11. The laminate structure of claim 9, further comprising: the
first metal sheet having a first thickness; the second metal sheet
having a second thickness; and the adhesive core having an adhesive
core thickness; wherein a ratio of the sum of the first and second
thickness to the adhesive core thickness is greater than eight to
one (8:1).
12. The laminate structure of claim 9, further comprising: the
adhesive core including a plurality of filler particles; wherein
the filler particles are made of an electrically conductive
material and are arranged in the adhesive core such that the
plurality of filler particles define an electrically conductive
path between the first and second metal sheets.
13. The laminate structure of claim 12, wherein each of the
adhesive core including the plurality of filler particles, the
first metal sheet, and the second metal sheet exhibit substantially
the same electrical conductivity.
14. The laminate structure of claim 12, wherein electrically
conductive material is an aluminum based material.
15. The laminate structure of claim 12, wherein the plurality of
filler particles are characterized by a particle size in a range of
-400 mesh and +500 mesh.
16. A method of making a laminate structure, the method comprising:
providing a first metal sheet; providing a second metal sheet;
wherein each of the first and second metal sheets are made of an
aluminum based material and include an inwardly facing surface;
applying an intermediate layer to the inwardly facing surfaces of
the first and second metal sheets at a consistent thickness and
coextensive with the inwardly facing surface to passivate the
inwardly facing surface; applying an adhesive core material to the
inwardly facing surface of the first metal sheet at a uniform
thickness and coextensive with the inwardly facing surface, such
that the intermediate layer is disposed between the adhesive core
material and first metal sheet; laminating the first metal sheet to
the second metal sheet such that the core material is disposed
between the first and second metal sheets to form the laminate
structure; wherein the steps of applying the intermediate layer,
applying the adhesive core material, and laminating the first metal
sheet to the second metal sheet are performed sequentially in a
continuous operation.
17. The method of claim 16, further comprising: applying a
deoxidation cleaner to the inwardly facing surfaces of the first
and second metal sheets immediately prior to applying the
intermediate layer; wherein the steps of applying the deoxidation
cleaner, applying the intermediate layer, applying the adhesive
core material, and laminating the first metal sheet to the second
metal sheet are performed sequentially in a continuous
operation.
18. The method of claim 16, wherein the intermediate layer includes
one of titanium, zirconium, and tri-chromium oxide.
19. The method of claim 16, wherein the adhesive core material is
made of one of a phenolic modified rubber material, and a polyester
based material.
20. The method of claim 16, further comprising: applying the
adhesive core material to the inwardly facing surface of the second
metal sheet at a uniform thickness and coextensive with the
inwardly facing surface, such that the intermediate layer is
disposed between the adhesive core material and second metal sheet.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of International Patent
Application PCT/US2015/028801 filed May 1, 2015, which is hereby
incorporated by reference in its entirety.
TECHNICAL FIELD
[0002] The present disclosure relates to a laminate of metal sheets
including a core layer disposed between and connected to the metal
sheets, and specifically, to a laminate including metal sheets of
an aluminum material.
BACKGROUND
[0003] Monolithic (solid) aluminum sheet is substantially less
dense than a monolithic (solid) steel sheet of the same thickness,
such that the monolithic aluminum sheet and/or structural
components formed therefrom presents a substantial weight savings
over the monolithic steel sheets and/or like components formed
therefrom. The monolithic aluminum sheet may be noisier, e.g., may
exhibit less favorable noise-vibration-harshness (NVH)
characteristics as compared with the monolithic steel sheet, due to
the density differences of the materials, where the monolithic
aluminum sheet is more susceptible to vibration and resonance and
more sensitive to frequency management than the monolithic steel
sheet. Components formed from monolithic aluminum sheet and/or
monolithic steel sheet often require modifying the components by
adding damping coatings and/or damping componentry such as damping
patches, for the components to provide acceptable NVH behavior.
Such added treatments, coatings and/or damping componentry add cost
and weight to the component formed from monolithic sheet. As such,
it is desirable to provide a sheet material which provides a weight
savings relative to monolithic steel sheet with improved damping
characteristics relative to monolithic aluminum sheet, which is
formable into structural components.
SUMMARY
[0004] A laminate structure and method of forming is described. The
laminate structure, which includes a viscoelastic adhesive layer
between and bonding aluminum sheets, is advantaged by being
formable into a structural component which provides desired levels
of vibration damping, sound transmission loss, structural
separation, etc. at a substantially lower weight relative to a
structural component formed of a monolithic metal sheet, and
without requiring added treatments, such as sound dampening
coatings or patches, to achieve the desired NVH performance. A
structural component, as that term is used herein, refers to a
component formed from sheet material which has a complex shape,
e.g., a shape other than flat sheet, and is used in a structural
application. For example, the complex shape of a structural
component can be defined by one or more features, such as one or
more of a bend, rib, aperture, bead, offset, chamfer, depression,
channel, curve, contour, extruded portion, or other feature formed
into the laminate structure to define the structural component. The
formed features defining the structural component create
discontinuities in the flatness of the laminate structure which
dissipate noise and increase sound transmission loss across, e.g.,
through, the structural component formed from the laminate
structure. As such, the laminate structure described herein can be
formed into structural components where there is a particular need
for noise dissipation, vibration and/or sound damping, structural
separation, thermal insulation and/or acoustic absorption, for
example, between spaces or areas separated by the structural
component(s) formed of the laminate structure. The term "structural
component" is non-limiting, such that a structural component may
have nominal or minimal load bearing requirements. In a
non-limiting example, the laminate structure described herein is
formable into structural components for vehicle applications, such
as close-out panels, also known as dash panels or trunk panels,
which provide structure to the vehicle by separating, respectively,
the engine compartment or trunk compartment from the passenger
compartment. Other non-limiting examples of vehicle structural
components which may be formed from the laminate structure include
wheel well liners, powertrain tunnel covers, floor pans, etc.
[0005] A laminate structure and method of forming is provided. The
laminate structure includes a first metal sheet having a first
thickness, a second metal sheet having a second thickness, and an
adhesive core having an adhesive thickness. The adhesive core is
disposed between and bonded to the first and second metal sheets.
The first and second metal sheets are made of an aluminum based
material and the adhesive core is made of an adhesive material
which may also be described herein as a viscoelastic adhesive
material. The adhesive core, in a non-limiting example, can be made
of one of a phenolic modified rubber material, an acrylic based
material, and a polyester based material. The laminate structure is
configured such that a ratio of the sum of the first and second
thickness to the adhesive thickness is greater than eight to one
(8:1). In a non-limiting example, the ratio of the sum of the first
and second thickness to the adhesive thickness is greater than
twenty-five to one (25:1). The laminate structure including the
viscoelastic adhesive core is a damping structure characterized by
a composite loss factor which is continuously greater than 0.1
within a predetermined temperature range defined by the application
of the component formed from the laminate structure. In one
example, the laminate structure is characterized by a composite
loss factor which is continuously greater than 0.1 within a
temperature range of 25 degrees Celsius to 50 degrees Celsius.
[0006] By way of example, the thickness of the first metal sheet is
within a range of 0.4 mm to 2.0 mm, the thickness of the second
metal sheet is within a range of 0.4 mm to 2.0 mm, and the adhesive
thickness, e.g., the thickness of the adhesive core, is within a
range of 0.013 mm to 0.076 mm. The density of the laminate
structure is substantially similar to the density of monolithic
aluminum, such that the density of the laminate structure is in a
range of 2.56 gm/cc to 2.70 gm/cc. The laminate structure is
characterized by one or more of an n value of 0.1 or greater, an r
value of 0.8 or greater, an adhesive strength as measured by T-peel
of at least 1.75 Newtons/millimeter (N/mm), and a lap shear
strength of at least 2 mega-Pascal (MPa).
[0007] By way of example, the laminate structure includes an
intermediate layer disposed between the adhesive layer and a
surface of one of the first and second metal sheets, where the
intermediate layer is a passivation layer acting to passivate the
surface of one of the first and second metal sheets. The laminate
structure may further include an auxiliary layer disposed between
the intermediate layer and the adhesive core and configured such
that the auxiliary layer is a corrosion prevention layer to prevent
the formation of corrosion at the bonding interface between the
adhesive core and the metal sheet. In one example, an isolation
layer is bonded to one of the first and second metal sheets such
that the isolation layer forms an exterior layer of the laminate
structure.
[0008] In one example, the adhesive core includes a plurality of
filler particles. In a non-limiting example, the filler particles
are made of an electrically conductive material, such as aluminum,
and are arranged in the adhesive core such that the plurality of
filler particles define an electrically conductive path between the
first and second metal sheets such that the laminate structure can
be joined by welding to another metallic component or structure. In
the present example, each of the adhesive core including the
plurality of filler particles, the first metal sheet, and the
second metal sheet exhibit substantially the same electrical
conductivity such that the laminate structure is weldable, e.g., is
attachable by resistance welding to another component or
structure.
[0009] The above features and advantages, and other features and
advantages, of the present teachings are readily apparent from the
following detailed description of some of the best modes and other
embodiments for carrying out the present teachings, as defined in
the appended claims, when taken in connection with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a schematic view of a cross-section of a first
example laminate structure including a core layer disposed between
aluminum sheets;
[0011] FIG. 2 is a schematic view of a cross-section of a second
example laminate structure including a core layer disposed between
aluminum sheets;
[0012] FIG. 3 is a schematic view of a cross-section of a third
example laminate structure including a core layer disposed between
aluminum sheets;
[0013] FIG. 4 is a schematic view of a cross-section of a fourth
example laminate structure including a core layer disposed between
aluminum sheets; and
[0014] FIG. 5 is a graphical illustration of composite loss factor
behavior of a plurality of laminate structures over a range of
operating temperatures.
DETAILED DESCRIPTION
[0015] The elements shown in FIGS. 1-5 are not necessarily to scale
or proportion, and the arrangement of elements shown in FIGS. 1-4
are not intended to be limiting. Accordingly, the particular
dimensions and applications provided in the drawings presented
herein are not to be considered limiting. Referring to the drawings
wherein like reference numbers represent like components throughout
the several figures, there is shown in FIGS. 1-4 a laminated
material generally indicated at 100, also referred to herein as a
laminate structure or as a laminate. The laminate 100 includes
opposing metal sheets 12, 14 which are connected by a core layer 10
disposed therebetween. Each of the metal sheets 12, 14 is made of
an aluminum based metal. The term "sheet" as used herein in the
context of aluminum materials is understood as being a rolled
aluminum alloy product with a uniform thickness of less than 6 mm.
By way of non-limiting example, each of the metal sheets 12, 14 may
be referred to herein as a skin, metal layer, aluminum sheet,
substrate, and/or base substrate. The core layer 10 includes an
adhesive core 16 which has NVH characteristics such that the core
layer 10 in combination with the aluminum sheets 12, 14 provide a
laminate structure 100 which is characterized as a noise damping
material exhibiting composite loss factor characteristics as shown
by exemplary lines 44, 46, 48 in FIG. 5. The adhesive core 16 may
also be referred to herein as a viscoelastic core 16, and/or the
adhesive core 16 may be characterized as being formed of a
viscoelastic material and/or having viscoelastic properties, such
that the viscoelastic core 16 substantially defines the damping
properties of the laminate structure 100. The core layer 10 is
disposed between the aluminum sheets 12, 14 such that the core
layer 10 spans substantially the entirety of (i.e., is coextensive
with) the metal layer 12 and the metal layer 14, adhering (i.e.,
rigidly attaching) the two aluminum sheets 12, 14 together such
that the core layer 10 is constrained by the metal layers 12, 14.
Notably, the laminate structure 100 may include additional layers
such as additional substrate layers and coating layers, and the
core layer 10 may include a plurality of layers including one or
more adhesive layers, sound-damping viscoelastic layers, coating
layers, electrically or thermally conductive layers, corrosion
prevention layers, etc. such that it would be understood that the
examples shown in FIGS. 1-4 are illustrative and are not intended
to be limiting.
[0016] The laminate structure 100 described herein may be formed
into structural components where there is a particular need for
enhancing structural reinforcement, vibration and/or sound damping,
thermal insulation and/or acoustic absorption, for example, between
spaces or areas separated by the structural component(s) formed of
the laminate structure 100. The laminate structure 100 described
herein, including aluminum sheets 12, 14 and core layer 10, is
advantaged by being formable into a structural component which
provides desired levels of vibration damping, sound transmission
loss, structural separation, etc. at a substantially lower weight
relative to a structural component formed of a steel based
material. The laminate structure 100 is advantaged by being
formable into a structural component which provides desired levels
of vibration damping, sound transmission loss, etc. at a
substantially lower weight relative to a structural component
formed from a monolithic metal sheet, and without requiring added
treatments, such as sound dampening coatings or patches, to achieve
the desired NVH performance. A structural component, as that term
is used herein, refers to a component formed from sheet material
which has a complex shape, e.g., a shape other than flat sheet, and
is used in a structural application. For example, the complex shape
of a structural component can be defined by one or more features,
such as one or more of a bend, rib, aperture, bead, offset,
chamfer, depression, channel, curve, contour, extruded portion, or
other feature formed into the laminate structure to define the
structural component. In the example described herein, the formed
features defining a structural component formed from the laminate
structure 100 create discontinuities in the flatness of the
laminate structure 100 which lowers the sound power transmitted
through the structural component formed from the laminate structure
100 and/or increases the sound transmission loss (STL) across
and/or through, the structural component formed from the laminate
structure 100. The formed features defining a structural component
formed from the laminate structure 100 create discontinuities in
the laminate structure 100 which can change the frequency of sound
waves as the sound waves are transmitted through the laminate
structure 100. For example, discontinuities created by formed
features in a component formed from the laminate structure 100
modify and/or change resonant frequencies of sound waves
transmitted through the laminate structure 100, relative to the
transmission of sound waves through a monolithic (solid) material.
As such, the laminate structure 100 described herein can be formed
into structural components where there is a particular need for
noise dissipation, vibration and/or sound damping, thermal
insulation and/or acoustic absorption, for example, between spaces
or areas separated by the structural component(s) formed of the
laminate structure 100. The term "structural component" is
non-limiting, such that a structural component can include
components having formed features which have nominal or minimal
load bearing requirements, although it would be understood that
formed features such as ribs, channels, beads, or other geometric
formed features included in a component formed from the laminate
structure 100 can increase the stiffness and/or rigidity of the
component. In a non-limiting example, the laminate structure 100
described herein is formable into structural components for vehicle
applications, such as close-out panels, also known as dash panels
or trunk panels, which provide structure to the vehicle by
separating, respectively, the engine compartment or trunk
compartment from the passenger compartment. Other non-limiting
examples of vehicle structural components which may be formed from
the laminate structure 100 include wheel well liners, powertrain
tunnel covers, floor pans, etc. In a non-limiting example, the core
layer 10 may be electrically conductive and/or the aluminum sheet
12, 14 may be coated such that the laminate structure 100 can be
joined by welding to another metallic component or structure.
[0017] In a preferred example the aluminum based material
comprising aluminum sheets 12, 14 is one of a 5xxx and 6xxx series
aluminum alloy having elongation greater than 15%, preferably
greater than 20%, and more preferably having an elongation of at
least 25%, and having an n value of at least 0.1 and an r value of
at least 0.8, where the n and r values characterize formability of
the aluminum sheet 12, 14. The "n value" as used herein is
understood as being the strain hardening exponent obtained by
calculating the slope of the true stress and true strain curve of
the material, where it is understood that increasing the n value
increases the formability of the material. The "r value" as used
herein is understood as being the Lankford value, also referred to
as the Lankford coefficient, plastic strain ratio, and/or plastic
anisotropy factor, and is a measure of the ratio of the true width
(or lateral) strain to the true thickness strain in a tensile test
of the aluminum sheet 12, 14. The r value indicates the capacity of
an aluminum sheet to resist thinning, where it is understood that
the higher the r value, the greater the resistance to thinning
during deep drawing. A 5xxx or 6xxx series aluminum alloy is
preferred for aluminum sheets 12, 14 to provide high elongation and
a heat stable structure such that the base substrates, e.g., the
aluminum sheets 12, 14, provide strength and stiffness while being
formable, for example, by stamping, extrusion, deep drawing, etc.
The aluminum material forming the aluminum sheets 12, 14 may be 1/4
hard or lower, such that the aluminum sheets 12, 14 are readily
formable. For example, the aluminum sheets 12, 14 may be provided
in an annealed temper condition also known as an "OT" temper, or in
a strain hardened tempered 1/4 hard condition also known as an "H2"
temper. In one example, a laminate structure 100 usable for forming
automotive components such as dash panels is formed of aluminum
sheets 12, 14 of a 6xxx series aluminum alloy provided with an OT
temper, such that the laminate structure 100 is readily formable by
pressing and/or stamping into complex shapes such as dash panels,
and is heat treatable, for example, during paint baking of the dash
panels and/or vehicle including the dash panels formed from the
laminate structure 100. The example of a 5xxx or 6xxx series
aluminum alloy material used for forming aluminum sheets 12, 14 is
non-limiting, and it would be understood that other aluminum alloys
may be used to form aluminum sheets 12, 14.
[0018] By way of non-limiting example and referring to FIG. 1, the
thickness T1, T2 of each aluminum sheet 12, 14 is in the range of
0.4 mm to 2.0 mm. In a preferred example, the thickness T1, T2 of
each aluminum sheet 12, 14 is in the range of 0.5 to 1.0 mm. In a
more preferred example, the thickness T1, T2 of each aluminum sheet
12, 14 is within the range of 0.6 mm to 0.8 mm. The thickness T1,
T2 of the aluminum sheets 12, 14 may be, but is not required to be,
the same thickness. For example, the thickness T1 of aluminum sheet
12 may differ from the thickness T2 of aluminum sheet 14 as
required by a particular use of the laminate structure 100, and/or
as required to form a particular component from the laminate
structure 100 and/or to provide functional characteristics such as
strength, stiffness, etc. required by the particular component
formed from the laminate structure 100. The combined (total)
thickness of the aluminum sheets 12, 14 and the adhesive core 16 is
controlled such that the laminate structure 100 is characterized by
an n value of at least 0.1, an r value of at least 0.8, an adhesive
strength as measured by T-peel of at least 10 pounds-force/inch and
a lap shear strength of at least 2 mega-Pascal such that the
laminate structure 100 is formable into structure components by
stamping, bending, extrusion and the like without separation of the
adhesive core 16 from the aluminum sheets 12, 14 or fracturing of
the aluminum sheets 12, 14. The examples are illustrative and
non-limiting, and it would be understood that one of the aluminum
sheets 12 could be a different aluminum material, temper, and/or
thickness than the other aluminum sheet 14.
[0019] The core layer 10 is disposed between the aluminum sheets
12, 14 such that the core layer 10 spans substantially the entirety
of (i.e., is coextensive with) the metal layer 12 and the metal
layer 14. The laminate structure 100 is formed by laminating the
metal sheets 12, 14 with the core layer 10 disposed therebetween
such that the core layer 10 adheres (i.e., rigidly attaches) the
two aluminum sheets 12, 14 together. The core layer 10 includes an
adhesive core 16, which substantially defines and/or provides the
NVH (noise, vibration, harshness) and damping performance
characteristics of the laminate structure 100. The core layer 10
and/or the adhesive core 16 has sufficient adhesive properties to
attach the two aluminum sheets 12, 14 to each other, and has
viscoelastic properties such that it dissipates vibrational energy
by converting the vibrational energy into thermal energy through
internal shearing of the adhesive material, such that the core
layer 10 and/or the adhesive core 16 acts as a damping layer to
damp sound power introduced on a source side of the laminate
structure 100 relative to the sound power transmitted from a
receiver side of the laminate structure 100. A sound transmission
loss (STL) factor of the laminate structure 100, or, for example, a
component formed from the laminate structure 100, can be expressed
as a ratio of the sound power on the source side of the component
formed from the laminate structure 100 with respect to the sound
power on the received side of the component formed from the
laminate structure 100, where it would be understood that the
source side of the component formed from the laminate structure 100
is that side of the laminate structure 100 or component formed
therefrom where the source of the sound (i.e., noise) is located,
and the received side of the component formed from the laminate
structure 100 is the side of the laminate structure 100 opposing
the source side where the sound is received (i.e., sensed), such
that the component formed from the laminate structure 100 is
disposed between the source side and the received side. In a
non-limiting example of an automotive component (not shown) formed
from the laminate structure, such as an automotive body panel, dash
panel, trunk panel, floor pan, engine tunnel cover, wheel well
liner, etc., formed from the laminate structure 100, the noise or
source of the sound may be road noise, powertrain or driveline
noise, noise from an engine or trunk compartment, aerodynamic noise
from the exterior of the vehicle, etc., exerting a sound power on
the exterior facing side (relative to the vehicle) of the component
formed from the laminate structure 100, such that the received
sound power is the power of the sound sensed in the interior of the
vehicle, e.g., by a passenger in the vehicle, where the received
side of the component formed from the laminate structure 100 is
that side of the vehicle component formed from the laminate
structure which is inwardly facing (relative to the vehicle), i.e.,
the interior side of the vehicle component. Formed features
defining the structural component formed from the laminate
structure 100 can create discontinuities in the flatness of the
laminate structure 100 which dissipate noise and increase sound
transmission loss across and/or through, the component formed from
the laminate structure 100.
[0020] The damping and/or NVH behavior of the laminate structure
100 and/or a component formed therefrom may be expressed in terms
of a composite loss factor, where the damping behavior and the
composite loss factor or a laminate structure 100 is a function of
frequency and is variable with the temperature at which the
laminate structure 100 is operating, e.g., the temperature of the
laminate structure in use in an application. As such, a laminate
structure 100 is characterized by a composite loss factor curve
such as one of the curves 44, 46, 48 of a composite loss factor
graph 40 shown in FIG. 5, where the composite loss factor (CLF) is
shown on the y-axis or vertical axis as shown on the page, and the
operating temperature at which the corresponding CLF is exhibited
is shown on the x-axis or horizontal axis as shown on the page. In
the example shown in FIG. 5, the CLF values at plotted for a
frequency of 1,000 Hertz (Hz). The temperature shown on the x-axis
is the ambient temperature of the environment in which the laminate
structure 100 is in use, such that the temperature shown on the
x-axis of graph 40 is substantially the operating temperature of
the laminate structure 100 at which the laminate structure 100
exhibits the corresponding CLF value shown on graph 40. In the
example shown, each of the curves 44, 46, 48 represent the
composite loss factor behavior of a respective one of a laminate
structure 100 including aluminum sheets 12, 14 and a core layer 10.
The CLF of a laminate structure 100 will vary, as shown in FIG. 5,
with temperature. In a preferred example, a composite loss factor
of greater than 0.10 (i.e. CLF>0.10) is desirable in a specified
operating temperature range for the laminate structure 100 or a
component formed therefrom. Referring again to FIG. 5, curve 42,
provided for comparison, shows the CLF of a steel laminate
structure formed of steel sheets attached by a viscoelastic core
layer and having a density of 7.842 grams/cubic centimeter (gm/cc).
By comparison, curve 46 shows the CLF of an aluminum laminate
structure 100 formed of aluminum sheets 12, 14 attached by a
viscoelastic core layer 10 and having a density of 2.71 gm/cc. Both
the steel laminate structure represented by curve 42 and the
aluminum laminate structure 100 represented by curve 46 have a
desirable CLF of greater than 0.10 in a broad operating temperature
range of 15 degrees Celsius to 65 degrees Celsius, however it would
be understood that the aluminum laminate structure 100 of curve 46
is advantaged by a significantly lower density such that in a
damping application the aluminum laminate structure 100 provides a
substantial weight savings relative to a steel laminate structure
providing comparable damping results.
[0021] Referring again to FIG. 1, in a non-limiting example the
adhesive core 16, which provides the NVH performance, e.g., acts as
the damping layer and attaches the aluminum sheets 12, 14 to each
other to form the laminate structure 100. The adhesive core 16 acts
as the damping layer by changing sound energy into heat via shear
action of the adhesive material forming the adhesive core 16, and
also acts to hold the aluminum sheets 12, 14 together during and
after forming of a component from the laminate structure 100. The
adhesive core 16 may be formed of a combination of one or more of
adhesive materials including one or more of an acrylic, polyester,
polyacrylate, phenolic, rubber and/or urethane based material. In a
preferred example, the adhesive core 16 is formed of a viscoelastic
material such as a phenolic modified rubber adhesive, a rubber
phenolic blend, or a rubber-based viscoelastic material. In other
examples the adhesive core 16 is formed of one of an acrylic
material, an acrylic rubber hybrid material, a polyester material
including a cross-linking agent, a rubber phenolic material, a
polyester rubber phenolic material, a polyacrylate material, a
polyester-based acrylic material, and a rubber phenolic blend. The
adhesive core 16 may be applied to the aluminum sheets 12, 14 to
provide a dry film thickness (DFT), e.g., an adhesive thickness T3
shown in FIG. 1, of the adhesive core 16 within the range of 0.0005
inches to 0.0030 inches (approximately 0.013 millimeters (mm) to
0.076 mm), where the damping performance of the laminate structure
100 and the thickness T3 of the adhesive core are inversely
related, e.g., the damping performance of the laminate structure
100, expressed in one example as a composite loss factor of the
laminate structure 100, improves as the thickness T3 of the
adhesive core 16 is decreased. In a preferred example to achieve
the desired damping performance of the laminate structure 100, the
thickness T3 of the adhesive core 16 is within the range of 0.001
inches to 0.0020 inches (0.025 mm to 0.0508 mm). In a more
preferred example, the thickness T3 of the adhesive core 16 is
within the range of 0.0010 inches to 0.0012 inches (0.025 mm to
0.03 mm). In a most preferred example, the thickness T3 of the
adhesive core 16 is less than 0.0010 inches (<0.025 mm), and/or
within the range of 0.0005 inches to 0.0010 inches (0.0125 mm to
0.025 mm).
[0022] The adhesive material forming the adhesive core 16 may be
applied to one of the aluminum sheets 12, 14 in a single layer
prior to laminating the aluminum sheets 12, 14 together with the
adhesive core 16 therebetween to form the laminate structure 100.
In a preferred example, the adhesive material forming the adhesive
core 16 may be applied in two adhesive layers 18, 20, as shown in
FIG. 2, to form the adhesive core 16. For example, a first adhesive
layer 18 may be applied to the aluminum sheet 14 and a second
adhesive layer 20 may be applied to the aluminum sheet 12 prior to
bringing the two aluminum sheets 12, 14 together during laminating.
In the preferred example, the bond strength and/or peel strength of
the laminate structure 100 including the first and second adhesive
layers 18, 20 bonded to each other is substantially higher relative
to a laminate structure 100 having an adhesive core 16 formed from
a single layer of adhesive material applied to one of the aluminum
sheets 12, 14 prior to laminating the lamination structure 100.
[0023] The thickness of each of the two adhesive layers 18, 20 is
controlled to provide the desired total dry film thickness T3 of
the adhesive core 16 in the finished laminate structure 100. By way
of non-limiting example, the overall thickness of the laminate
structure 100, exclusive of exterior layers 26, 28 and isolation
layers 34, may be in the range of 0.813 mm to 4.76 mm. For example,
a laminate structure 100 may include aluminum sheets 12, 14 each
having a thickness T1, T2 of 0.4 mm and an adhesive core having a
thickness T3 of 0.013 mm for a total thickness (T1+T2+T3) of 0.813
mm and an aluminum to adhesive thickness ratio of 61.5, where the
aluminum to adhesive thickness ratio is calculated as (T1+T2)/T3.
In another example, a laminate structure 100 may include aluminum
sheets 12, 14 each having a thickness T1, T2 of 2.0 mm and an
adhesive core having a thickness T3 of 0.076 mm for a total
thickness of 4.076 mm and an aluminum to adhesive thickness ratio
of 52.6. In a preferred example, the overall thickness of the
laminate structure 100 may be in the range of 1.45 mm to 1.66 mm.
For example, a laminate structure 100 in the preferred thickness
range may include aluminum sheets 12, 14 each having a thickness
T1, T2 of 0.6 mm and an adhesive core 16 having a thickness T3 of
0.025 mm for a total thickness of 0.1.45 mm. In another preferred
example, a laminate structure 100 may include aluminum sheets 12,
14 each having a thickness T1, T2 of 0.8 mm and an adhesive core
having a thickness T3 of 0.06 mm for a total thickness of 1.66 mm.
In a preferred example, the ratio of the combined thickness (T1+T2)
of the aluminum sheets 12, 14 to the thickness T3 of the adhesive
core 16 is within the range of 25 to 50, where it would be
understood that the thickness T1, T2 of the aluminum sheets 12, 14
substantially contributes the tensile strength and rigidity to the
laminate structure 100, and the thickness T3 of the adhesive core
16 substantially contributes to the damping characteristics of the
laminate structure 100, and where the thickness ratio influences
the CLF behavior of the laminate structure 100. It would be
understood that a thinner adhesive core 16 is desirable to
contribute damping to the laminate structure 100 while minimizing
impact on rigidity and tensile strength of the laminate structure
100. By way of example, the laminate structure 100 may be
characterized by an adhesive thickness ratio in the range of 8:1 to
50:1. The laminate structure 100 having an aluminum to adhesive
thickness ratio ((T1+T2)/T3) of 8:1 or more is characterized by a
density substantially similar to that of monolithic (solid)
aluminum, which has a density of 2.7 gm/cc. In a preferred example,
a laminate structure 100 having an aluminum to adhesive thickness
ratio ((T1+T2)/T3) of 25:1 has a density of at least 2.56 gm/cc,
such that the density of the laminate structure 100 is at least 95%
that of monolithic aluminum, contributing to the rigidity and
strength of the laminate structure 100. In a preferred example, the
laminate structure 100 has a density of at least 2.64 gm/cc.
[0024] The adhesive material of the adhesive layers 18, 20 may be,
in a non-limiting example, one of a polyester based material which
may be a cross-linking polyester, an acrylic based material which
may optionally include a cross-linking agent to provide relatively
higher resistance to chemical attack, and a phenolic modified
rubber. In one example, the adhesive core 16 formed from the
phenolic modified rubber material may be characterized by a matrix
structure including rubber dispersed in a phenolic matrix such that
bond strength of the laminate structure 100 is substantially
defined by, e.g., resultant from, the bonding of the phenolic to
the aluminum sheets 12, 14 and the bonding of the phenolic to the
dispersed rubber particles. The adhesive material may be applied to
the aluminum sheet 12, 14 by any suitable technique, including, for
example, spraying, hot melt and/or rolling techniques by which the
adhesive material is applied to the aluminum sheet 12, 14, and
where the adhesive material may be used to ensure wetting out of
the adhesive material which may be a solvent based adhesive
material, on the aluminum sheet 12, 14, to provide full coverage of
the aluminum sheet 12, 14 at the desired thickness prior to
laminating the aluminum sheets 12, 14 together. In another example,
the adhesive material may be provided as a dry adhesive film and
applied to one or both of the aluminum sheets 12, 14 prior to
laminating. The dry adhesive film can be applied, for example, in a
continuous process where the dry adhesive film is interleaved
between the aluminum sheets 12, 14 prior to laminating. The dry
adhesive film may include a liner which is removed from the dry
adhesive film after application of the film to the aluminum sheet
12, 14 and prior to laminating the aluminum sheets 12, 14 together.
The adhesive material is heated and/or cured during the laminating
process forming the laminate structure 100 by a means suitable to
the type of the adhesive material being applied, which may include
one or a combination of exposing the adhesive material to elevated
temperatures, for example, using flame bars, incinerator ovens, hot
air ovens, etc., and/or hot melt, infrared, and ultraviolet systems
as understood by those knowledgeable in the field of laminating.
The examples are non-limiting, and it would be understood that
other forms of adhesive materials such as dry powder or web forms,
application methods and curing processes may be used within the
scope of forming the laminate structure 100 including the aluminum
sheets 12, 14 and the core layer 10 described herein.
[0025] The adhesive material forming the core layer 10 and/or the
adhesive core 16 is characterized by an elongation which is
substantially greater than the elongation of the aluminum material
comprising the aluminum sheets 12, 14, such that during deformation
of the laminate structure 100, for example, during stamping,
extrusion, and/or bending of the laminate structure 100 to form a
component therefrom, the core layer 10 remains in an elastic range
and does not separate from the edges of and/or between the aluminum
sheets 12, 14 of the laminate structure 100, where it would be
understood that separation of the adhesive core 16 from the
aluminum sheets 12, 14 would affect the damping characteristics of
the laminate structure 100 in the localized area where the
separation occurred. By way of non-limiting example, the core layer
10 and/or the adhesive core 16 is characterized by a minimum
elongation of 150%. In a preferred example, the core layer 10
and/or the adhesive core 16 is characterized by a minimum
elongation of 300%, and in a more preferred example, an elongation
in the range of 300% to 400%. Preferably, a minimum elongation
ratio of ten (10) is maintained for the laminate structure 100,
where the elongation ratio is expressed as the elongation of the
core layer 16 relative to (divided by) the elongation of the
thinner of the aluminum sheets 12, 14, to prevent fracture of the
core layer 16 and maintain the damping capacity of the laminate
structure 100. In a more preferred example, the laminate structure
100 is characterized by a minimum elongation ratio of twenty (20).
In a most preferred example, the laminate structure 100 is
characterized by a minimum elongation ratio in the range of twenty
(20) to thirty (30). In one example, the laminate structure 100
includes 5XXX (series aluminum sheets 12, 14 each having a
thickness T1, T2 of 0.80 mm and an elongation in the range of 18%
to 22% and a phenolic modified rubber adhesive core 16 having a
nominal thickness T3 of 0.025 mm and an elongation of 300% such
that the example laminate structure 100 is characterized by an
elongation ratio of 13.6 to 16.7.
[0026] In a preferred example for forming the core layer 16 and
laminate structure 100, an adhesive material is selected, applied
to one or both of the aluminum sheets 12, 14, cured and laminated
to provide a laminate structure 100 which is characterized by an
adhesive strength as measured by T-peel of at least ten
pounds-force/inch (10 lbf/in or approximately 1.75
Newtons/millimeter (N/mm)) using a T-peel strength test performed
for example, in compliance with ASTM D1876 at a 10 inch/minute pull
rate, a lap shear strength of at least two mega Pascal (2 MPa) a
lap shear strength test performed for example, in compliance with
ASTM D1002, a yield strength of 100-120 kilo-pounds per square inch
(KSI) with an ultimate tensile strength of 200-250 KSI where
plastic failure of at least one of the aluminum sheets 12, 14
occurs prior to plastic failure of the adhesive core 16. In a most
preferred example, the laminate structure 100 is characterized by
an adhesive strength as measured by T-peel of at least fifteen
foot-pounds/inch (15 lbf/in or approximately 2.63 N/mm).
[0027] In a preferred example, the laminated structure 100 retains
a minimum of 80% of the original bond strength, as indicated by lap
shear strength and T-peel strength, after heat cycle aging, after
thermal cycle (cold shock or cold/hot thermal cycling testing, for
example, between -30 degrees C. and +105 degrees C.) testing, and
after cyclic corrosion testing (for example, SAE J2334 testing),
where the criteria for each of these is application specific for
the intended use of the laminate structure 100 or a component
formed therefrom. In one example, the laminate structure 100 is
characterized by retaining 80% of the original bond strength after
being subjected to heat cycle aging at 205 degrees Celsius for 40
minutes, to provide a laminate structure 100 which can be subjected
during a coating process cycle such as electro-coating
(electrostatic coating or E-coat) cycle or painting cycle to a
baking operation where the laminate structure 100 is heated in a
paint or e-coat oven in excess of 100 degrees Celsius and up to 205
degrees Celsius, without degradation of the laminate structure 100
or component formed therefrom. For example, such a laminate
structure 100 is suitable for forming into an automotive component
such as a dash panel, etc., which may be e-coated or painted. In
the preferred example, the laminate structure 100 is able to
withstand a 90 degree 1T radius bend at 0.75 inch flange length
without degradation, where T is the thickness of the laminate
structure 100 expressed in inches, where in the present example the
laminate structure 100 includes aluminum sheets 12, 14 made of 5xxx
series aluminum material and an adhesive core 16 made of phenolic
modified rubber, the laminate structure 100 having a total
thickness of approximately 0.072 inches. The laminate structure 100
of the present example in an Olsen dome tensile test can be pressed
by a 1 inch ball to a depth of 0.360 inches prior to rupture, e.g.,
prior to fracture of the aluminum sheet 12, 14. In a preferred
example, a laminate structure 100 includes aluminum sheets 12, 14
made of 5xxx series aluminum material with an "0" temper to provide
high elongation with relatively low tensile strength such that
minimal springback occurs during and after forming of a component
from the laminate structure 100, e.g., such that the laminate
structure 100 exhibits forming characteristics similar to a deep
draw grade ferrous material.
[0028] The laminate structure 100 exhibits a bending rigidity at
room temperature (approximately 23 degrees Celsius) which is at
least 35% that of a solid (monolithic) aluminum sheet having a
thickness equal to the combined thickness (T1+T2) of the aluminum
sheets 10, 12. In a preferred example, the laminate structure 100
exhibits a bending rigidity at room temperature of 50% or more
relative to a monolithic aluminum sheet having a thickness equal to
the combined thickness (T1+T2) of the aluminum sheets 10, 12. In a
more preferred example, the laminate structure 100 exhibits a
minimum bending rigidity at room temperature of 50% to 60% of that
of a monolithic aluminum sheet having a thickness equal to the
combined thickness (T1+T2) of the aluminum sheets 10, 12.
[0029] Referring to FIG. 5, the laminate structure 100 and
components formed therefrom are advantaged by the combination of a
light weight structure (relative to a steel structure of comparable
thickness) and damping performance illustrated by the exemplary CLF
curves 44, 46, 48 shown in graph 40 of FIG. 5. In a preferred
example, a composite loss factor of greater than 0.10 (i.e.
CLF>0.10) is desirable in a specified operating temperature
range for the laminate structure 100 or a component formed
therefrom to provide damping in at the specified operating
temperature. Referring again to FIG. 5, curve 42 is provided for
comparison and shows the CLF of a steel laminate structure formed
of steel sheets attached by a viscoelastic core layer and having a
density of 7.842 gm/cc. By comparison, curve 46 shows the CLF of an
aluminum laminate structure 100 formed of aluminum sheets 12, 14
attached by a viscoelastic core layer 10 and having a density of
2.71 gm/cc. Both the steel laminate structure represented by curve
42 and the aluminum laminate structure 100 represented by curve 46
have a desirable CLF of greater than 0.10 in a broad operating
temperature range of 15 degrees Celsius to 65 degrees Celsius, such
that the aluminum laminate structure 100 and the steel laminate
structure have comparable damping capabilities, however it would be
understood that the aluminum laminate structure 100 of curve 46 is
advantaged by a significantly lower density, e.g., a density which
is 34.5% that of the steel laminate of curve 42, such that in a
damping application the aluminum laminate structure 100 provides a
substantial weight savings relative to a steel laminate structure
while providing comparable damping results.
[0030] Curves 44, 46 and 48 provide illustrative comparative
examples of laminate structures 100 each including aluminum sheets
12, 14 and a viscoelastic adhesive core 16, having similar density
and stiffness, and substantially the same aluminum to adhesive
thickness ratio, however differing in the adhesive material used to
form the adhesive core 16. As such, a comparison of the curves 44,
46, 48 illustrates the influence of the adhesive material used to
form the adhesive core on the CLF behavior of the resulting
laminate structure 100, and specifically the influence of the
adhesive material forming the adhesive core 16 on the temperature
range in which the laminate structure 100 exhibits a CLF at or
above the desired CLF value of 0.1. For example, curve 44
corresponds to a laminate structure 100 including an adhesive core
16 formed of a phenolic modified rubber material exhibiting a CLF
continuously above 0.1 in the temperature range of approximately 12
degrees Celsius to 52 degrees Celsius, such that the laminate
structure 100 of curve 44 demonstrates desirable damping
characteristics at +/-10 degrees Celsius from room temperature,
where room temperature is understood to be 23 degrees Celsius on
average. Curve 46 corresponds to a laminate structure 100 including
an adhesive core 16 formed of an acrylic material, and exhibiting a
CLF continuously above 0.1 in the temperature range of
approximately 15 degrees Celsius to 70 degrees Celsius, such that
the laminate structure 100 corresponding to curve 46 can be used in
environments requiring damping at relatively higher operating
temperatures. Curve 48 corresponds to a laminate structure 100
including an adhesive core 16 formed of a cross-linked polyester
material, and exhibiting a CLF continuously above 0.1 in the
temperature range of approximately 25 degrees Celsius to at least
60 degrees Celsius. As shown on FIG. 5, each of the example curves
44, 46, 48 illustrate a laminate structure 100 having a CLF which
is continuously above (greater than) 0.1 for operating temperatures
ranging from room temperature (approximately 23 degrees Celsius) up
to at least 50 degrees Celsius.
[0031] As shown in FIG. 1, the core layer 10 may include one or
more intermediate coating or treatment layers 22, 24 which may be
referred to herein as intermediate layers 22, 24. In the example
shown, a first intermediate layer 22 is disposed between the
adhesive core 16 and the aluminum sheet 12 such that the
intermediate layer 22 spans substantially the entirety of (i.e., is
coextensive with) the aluminum sheet 12 and the adhesive core 16,
and a second intermediate layer 24 is disposed between the adhesive
core 16 and the aluminum sheet 14 such that the intermediate layer
24 spans substantially the entirety of (i.e., is coextensive with)
the aluminum sheet 14 and the adhesive core 16. The example shown
in FIG. 1 is non-limiting, and it would be understood that the
laminate structure 100 may be constructed including both of the
intermediate layers 22, 24, one of the intermediate layers 22, 24,
or neither of these. The intermediate layer 22, 24 prepares the
surface of the respective aluminum sheet 12, 14 to which it is
applied, to passivate the surface of the aluminum sheet 12, 14 to
increase the surface bonding potential of the respective aluminum
sheet 12, 14 to bond with the adhesive material of the adhesive
core 16, and/or to resist corrosion at the bond interface between
the adhesive core 16 and the respective aluminum sheet 12, 14 to
prevent degradation of the bond between the adhesive core 16 and
the respective aluminum sheet 12, 14, for example, by preventing
formation of a corrosion product at the bond interface.
[0032] The aluminum sheet 12, 14 may be prepared, e.g., pretreated,
prior to applying the intermediate layer 22, 24 by cleaning the
aluminum sheet 12, 14 with a deoxidation cleaner such as an
alkaline cleaner or an acidic cleaner to remove soil, oil, grease,
etc. from the surface of the aluminum sheet 12, 14 and to remove
any aluminum oxide product from the surface of the aluminum sheet
12, 14, to prepare the surface of the aluminum sheet 12, 14 to
receive the intermediate layer 22, 24. As such, the deoxidation
cleaner creates a "fresh" aluminum surface which, if not
subsequently treated, e.g., coated, within a period of time, will
reoxidize. As such, the deoxidation cleaner removes the oxide layer
from surface of the aluminum sheet 12, 14 to temporarily increase
bonding receptivity of the aluminum sheet, for example, to one of
the layers 22, 24, 24, 32 described further herein. In a
non-limiting example, the aluminum sheet 12, 14 may be cleaned
and/or pretreated applying the cleaning solution using, for
example, immersion cleaning, spray cleaning, rolling on the
cleaning solution, or using other suitable chemical cleaning means
to apply the deoxidation cleaner. In another example, the aluminum
sheet 12, 14 may be mechanically cleaned to deoxidize, e.g., remove
the oxide layer from, the surfaces of the aluminum sheet 12,
14.
[0033] In one example, the intermediate coating 22, 24 may be
applied at a coating weight thickness (CWT) in the range of 2.0 to
10.0 milligram/square meter (mg/m.sup.2) by spraying the
intermediate coating 22, 24 in solution form onto the aluminum
sheets 12, 14 or immersing the aluminum sheets 12, 14 in the
coating solution. In one example, the intermediate coating 22, 24
is applied as a solution containing titanium and zirconium which
passivates the aluminum surface of the aluminum sheet 12, 14, and
prevents activation of the aluminum surface over time. In another
example, the intermediate coating 22, 24 is applied as a solution
containing tri-chromium oxide. The coating solution may also be
applied to the exterior surfaces, e.g., the outwardly facing
surfaces, of the aluminum sheets 12, 14 to form exterior coating
layers 28, 26, as shown in FIG. 2, to passivate and/or increase the
surface bonding potential of the exterior (outwardly facing)
surface of the aluminum sheet 12, 14, as a pretreatment for further
coating and/or painting of the laminate structure 100 or a
component formed therefrom, and/or to provide a corrosion
prevention coating 26, 28 on the laminate structure 100.
[0034] As shown in FIG. 3, an auxiliary coating layer 30, 32 may be
applied between the intermediate layer 22, 24 and the core layer 16
such that the auxiliary coating layer 30, 32 spans substantially
the entirety of (i.e., is coextensive with) the core layer 16. Each
of the auxiliary coating layers 30, 32 may also be referred to
herein as an auxiliary layer 30, 32. In one example, the auxiliary
layer 30, 32 may be a titanium and zirconium containing coating
similar to the passivation layer 22, 24, such that the laminate
structure 100 includes first and second layers 22, 30 between the
adhesive core 16 and the aluminum sheet 12 and first and second
layers 24, 32 between the adhesive core 16 and the aluminum sheet
14, where the dual layering of the titanium-zirconium containing
layers 22, 30 and 24, 32 first passivates the aluminum surface then
increases the receptivity of bonding of the adhesive core 16 to the
aluminum sheet 12, 14. The increased receptivity provided by the
dual layering increases the bond strength at the bond interface
between the adhesive core 16 and the aluminum sheet 12, 14
resulting in a relatively higher peel strength, for example,
greater than 10 lbf/in, while retaining the desired damping
performance, for example, a CLF of greater than 0.1 within +/-10
degrees Celsius of the target operating (in use) temperature of the
laminate structure 100 and/or a component formed therefrom.
[0035] In one example, the laminate structure 100 may include at
least one of the auxiliary layer 30, 32 which is a corrosion
prevention layer to prevent contaminant ingression at the bonded
interface between the adhesive core 16 and the adjacent aluminum
sheet 12, 14, for example, by preventing contaminant ingression at
an exposed edge of the laminate structure 100. In another example,
the laminate structure 100 may include at least one auxiliary layer
30, 32 configured as a thermal coating to modify the thermal
emissivity and/or thermal conductivity of the laminate structure
100. For example, at least one auxiliary layer 30, 32 may be made
of a heat dissipating material to dissipate heat away from the
adhesive core 16, or may be made of a heat absorptive material to
absorb heat into the laminate structure 100. In another example,
the laminate structure 100 may include at least one auxiliary layer
30, 32 configured as an electrically conductive layer to modify the
electrical conductivity of the laminate structure 100. For example,
the laminate structure 100 shown in FIG. 3 could include auxiliary
layers 30, 32 which are made of or include an electrically
conductive material, such as a carbon-based or graphite-based
material or graphite film, and could further include an adhesive
core as shown in FIG. 4, where the adhesive core 16 includes an
electrically conductive filler 36 such as an aluminum particle
filler or graphite filler such that the adhesive core and the
auxiliary layers 30, 32 are electrically conductive and the
laminate structure 100 is electrically conductive. The example
shown in FIG. 3 is non-limiting, and it would be understood that
the laminate structure 100 may be configured with one or both
auxiliary layers 30, 32, with a plurality of auxiliary layers 30
disposed between the adhesive core 16 and the aluminum sheet 12,
with a plurality of auxiliary layers 32 disposed between the
adhesive core 16 and the aluminum sheet 14, and/or without either
auxiliary layer 30, 32. It would be understood that each of the
auxiliary layers 30, 32 may be similarly configured, e.g., be made
of the same material and/or have the same thickness, or may be
differently configured, e.g., made of different materials and/or
have different thicknesses and/or be included to provide different
functionalities (corrosion prevention, thermal conductivity,
electrical conductivity, etc.) to the laminate structure 100.
[0036] Referring to FIG. 2, the laminate structure 100 may include
one or more exterior coating layers 26, 28, which may be referred
to herein as exterior coatings 26, 28 and/or as exterior layers 26,
28. In the example shown, an exterior layer 28 is applied to, e.g.,
bonded, adhered, laminated or otherwise attached to, the exterior
(outwardly facing or outermost) surface of the aluminum sheet 12
such that the exterior layer 28 spans substantially the entirety of
(i.e., is coextensive with) the aluminum sheet 12, and an exterior
layer 26 is applied to, e.g., bonded, adhered, laminated or
otherwise attached to the exterior (outwardly facing or outermost)
surface of the aluminum sheet 14 such that the exterior layer 28
spans substantially the entirety of (i.e., is coextensive with) the
aluminum sheet 12. The example shown in FIG. 2 is non-limiting, and
it would be understood that the laminate structure 100 could be
configured with one, both, or neither of the exterior layers 26,
28. The exterior coating layers 28, 26 may be configured to
passivate and/or increase the surface bonding potential of the
exterior (outwardly facing) surface of the aluminum sheet 12, 14,
as a pretreatment for further coating and/or painting of the
exterior surfaces of the laminate structure 100 or a component
formed therefrom, and/or to provide a corrosion prevention coating
26, 28 on the laminate structure 100. The laminate structure 100
can include a plurality of exterior layers 26 and/or a plurality of
exterior layers 28 applied in a predetermined sequence. By way of
non-limiting example, the laminate structure 100 could include a
first exterior layer 28 applied to, e.g., bonded, to the aluminum
sheet 12, as a pretreatment for further coating and/or painting of
the exterior (outwardly facing) surface of the aluminum sheet 12
with an additional exterior layer 28 which may be, by way of
non-limiting example, a paint layer, a decorative coating layer, a
corrosion protection layer, a thermal coating layer, etc. In one
example, the exterior layer 26, 28 is a heat reflective thermal
coating layer, such as a solar reflective layer, to reflect heat
from and/or decrease heat absorption into the laminate structure
100. In another example, the exterior layer 26, 28 is a heat
absorptive thermal coating layer, such as a low emissivity coating
layer or black paint layer, to increase heat absorption into the
laminate structure 100.
[0037] In one example, at least one of the exterior layers 26, 28
may be configured as an isolation layer 34, as shown in FIG. 4,
where an "isolation layer" as that term is used herein, is a layer
of material bonded to the laminate structure 100 to form an
exterior layer of the laminate structure 100, and configured to
prevent corrosion of the laminate structure 100 and/or to protect
the aluminum layers 12, 14 to which the isolation layer 34 is
applied, for example, from chemical attack and/or exposure to
contaminants. In one example, the isolation layer 34 is configured
to prevent galvanic corrosion when the laminate structure 100
and/or a component formed therefrom is in contact with, connected
and/or fastened to a steel component. The isolation layer 34 may
also be referred to herein as a galvanic isolation layer 34. In one
example, the galvanic isolation layer 34 can consist of a polymer
binder with zinc particles disbursed and embedded therein, with the
polymer layer preventing corrosion by preventing ion transfer
through the isolation layer, and the zinc particles preferentially,
e.g., sacrificially, absorbing ions to prevent corrosion of the
aluminum sheet 12, 14. The examples shown in the figures are
non-limiting. For example, an exterior layer 26, 28 may be disposed
between the aluminum sheet 14, 12 and a galvanic isolation layer
34. By way of example, the galvanic isolation layer 34 may be
applied to one or both exterior surfaces of the laminate structure
100. In one example, organic coatings, including zinc rich primer
coatings such as Granocoat.RTM. or Bonazinc.TM. and/or modified
epoxy or polyester based weldable paints and/or primers may be used
to form the isolation layer 34.
[0038] Referring to FIG. 4, the adhesive core 16 can include filler
particles 36 distributed in the adhesive material forming the
adhesive core 16. The size, shape, configuration, material, density
and dispersion pattern of the filler particles 36 may be selected
to provide a desired functional attribute of the core layer 10
and/or the adhesive core 16. The filler particles 36 may be coated,
for example, with a wetting agent to provide for uniform dispersion
and mixing of the filler particles 36 in the adhesive material
forming the adhesive core 16. In one example, the adhesive core 16
is a phenolic modified rubber including a plurality of rubber
filler particles 36. The phenolic bonds with the aluminum sheets
12, 14 and the rubber particles bond to the phenolic, to contribute
bond strength and peel strength to the laminate structure 100. In
another example, the filler particles 36 may be configured to
modify the thermal conductivity of the laminate structure 100. In
one example, the filler particles 36 may be configured to increase
the insulating characteristics of the laminate structure. In
another example, the filler particles 36 may comprise a high
directional thermal conductivity material to increase the thermal
dissipation from a point or localized source of the laminate
structure 100, for example, when the laminate structure 100 is
intended for use in a heat shielding application and thermal
dissipation of heat away from the area being shielded by the
laminate structure 100 is required. In one example, the filler
particles 36 may be carbon particles, such as carbon nano-particles
in the form of nanotubes, nanofibers or nanoflakes, dispersed in
the adhesive core 16 to provide a thermal conductive path through
the core layer 10. In another example, a graphite foil may be
laminated between the adhesive layers 18, 20 to provide a heat
conductive graphite structure, for heat shield or other thermal
conductive applications of the laminate structure 100.
[0039] In one example, the filler particles 36 are electrically
conductive and provided in a size and/or shape and are dispersed in
the adhesive core 16 at a density or dispersion pattern such that
the electrically conductive filler particles 36 provide a
conductive path through the adhesive core 16 to form an
electrically conductive laminate structure 100. The electrically
conductive filler particles 36 may be configured such that the
filler particles 36 and the aluminum sheets 12, 14 have
substantially similar, e.g., substantially the same, conductivity,
and such that the electrical resistance of the core layer 10 is
substantially equal to or less than the electrical resistance of
each of the aluminum sheets 12, 14, and such that the electrical
resistance of the core layer 10 including the filler particles 36
is substantially less than the electrical resistance of the
adhesive material in the adhesive core 16. In a non-limiting
example, the electrically conductive filler particles 36 are an
aluminum material containing at least 99.8% aluminum, such that the
material chemistry and the electric potential of the filler
particles 36 are substantially similar to that of the aluminum
sheets 12, 14 to prevent galvanic corrosion of and/or the formation
of a galvanic cell within the laminate structure 100. The adhesive
material forming the adhesive core 16 may be configured to prevent
ion transfer through the adhesive core 16 when an electrical
current is conducted through the laminate structure 100, as an
alternate means to prevent formation of a galvanic cell and/or to
prevent galvanic corrosion of the laminate structure 100. The size,
shape and dispersion of the filler particles 36 may be configured
to provide a conductive path through the core layer 10 when the
filler particles 36 are dispersed in the adhesive core 16. By way
of non-limiting example, the aluminum filler particles 36 may be
shaped as one or a combination of whiskers, shavings, fibers,
spheroids, ellipsoids, ovoids, cylinders, polyhedrons, etc. which
may be symmetrical and/or asymmetrical, and/or may be regular
and/or irregular in shape. In one example, the aluminum filler
particles may be approximately 0.030 millimeters (mm) in size,
e.g., may have a major dimension (the largest dimension of the
filler particle 36) which is in the range of 0.025 mm to 0.038 mm,
such that the filler particle 36 is passable through a 400 mesh
screen and retained by a 500 mesh screen, e.g., the particle size
can be expressed as being between -400 mesh and +500 mesh in size.
The filler particles 36 may be, but are not required to be, of
uniform shape and/or size. In one example, the size of the filler
particles 36 may be varied, such that the adhesive core 16 may
include filler particles 36 of a single shape in various sizes, or
may include filler particles 36 of multiple shapes in various
sizes.
[0040] In one example, the volume of electrically conductive filler
particles 36 distributed in the core layer 10 is at least 2% of the
total volume of the core layer 10 after lamination and curing of
the laminate structure 100. As the volume of filler particles 36
increases in the adhesive core 16, the bond strength may decrease
proportionally, such that in one example, the volume of
electrically conductive filler particles 36 distributed in the core
layer 10 is less than 15% after lamination and curing of the
laminate structure 100, and in another example is less than 10%. In
a preferred example, the volume of electrically conductive filler
particles 36 distributed in the core layer 10 is within the range
of 2% to 8% of the total volume of the core layer 10 after
lamination and curing of the laminate structure 100, in a more
preferred example, the volume of electrically conductive filler
particles 36 is within the range of 2% to 6%, and in a most
preferred example is within the range of 2% to 4% of the total
volume of the core layer 10 after lamination and curing of the
laminate structure. The volume of electrically conductive filler
particles 36 in the adhesive core 16 may also be expressed as a
percentage of the total weight of the adhesive core 16 after
lamination and curing of the laminate structure 100. In the example
of electrically conductive filler particles 36 which are made
substantially of aluminum, the percent by weight of aluminum filler
particles 36 distributed in the adhesive core 16 can be in the
range of 5% to 37.5% of the total weight of the adhesive core 16.
As noted previously, the bond strength of the bond interface
between the core layer 10 and the aluminum sheets 12, 14 may
decrease with an increase in the volume of filler particles 36,
such that in one example the percent by weight of aluminum filler
particles 36 distributed in the adhesive core 16 is within the
range of 5% to 20%, in a preferred example is in the range of 5% to
15%, and in a more preferred example is in the range of 5% to 10%
by weight.
[0041] By way of non-limiting example, a method of forming the
laminate structure 100 includes presenting the various layers
required to form the laminate structure 100 in the required
sequence to a laminating process which includes applying a
laminating pressure to the sequenced layers and curing the layered
structure such that the layers are bonded together to form the
laminate structure 100. By way of non-limiting and illustrative
example and referring to FIG. 2, the laminate structure 100 is
formed by cleaning the aluminum sheets 12, 14, as previously
described herein, to deoxidize the surfaces of the aluminum sheets
12, 14. The inwardly facing surfaces of the aluminum sheets 12, 14,
e.g., the surfaces which are to be bonded to the adhesive core 16,
are respectively coated with the intermediate layers 22, 24, for
example by spray, roller and/or immersion application of the
coating material forming the intermediate layers 22, 24, where the
applied coating material is wetted out, e.g., distributed, on the
inwardly facing surfaces of the aluminum sheets 12, 14 such that
the coating material covers the entire surface of the aluminum
sheet 12, 14, e.g., is coextensive with the surface of the aluminum
sheet 12, 14, at a uniform coating thickness sufficient to provide
the desired thickness of the respective intermediate layers 22, 24
after laminating and curing the laminate structure 100. In one
example, coating material may be applied to the exterior (outwardly
facing) surfaces of the aluminum sheets 12, 14 to form the exterior
layers 28, 26, for example, by spray, roller and/or immersion
application, and wetted out, e.g., distributed, on the outwardly
facing surfaces of the aluminum sheets 12, 14 such that the coating
material covers the entire surface of the aluminum sheet 12, 14,
e.g., is coextensive with the surface of the aluminum sheet 12, 14,
at a uniform coating thickness sufficient to provide the desired
thickness of the respective exterior layers 28, 26 after laminating
and curing the laminate structure 100. The coating material may be
solvent based, such that the aluminum sheets 12, 14 may be
subjected to a drying operation to dry and/or cure the intermediate
layers 22, 24 and/or the exterior layers 26, 28, which may include
air drying or exposing the coated aluminum sheets 12, 14 to heat
provided by one or more of a flame bar, incinerator oven, baking
oven, infrared, etc., as required to dry and/or cure the
intermediate layers 22, 24 and exterior layers 28, 26. In another
example, the laminate structure 100 may be laminated without one or
both of the exterior layers 28, 26, and/or one or both of the
exterior layers 28, 26 may be applied to the laminate structure 100
after lamination and curing of the laminate structure 100, for
example, as a paint or e-coat layer, or an isolation layer 36, as
previously described herein.
[0042] Still referring to the illustrative example shown in FIG. 2,
and after forming the intermediate layers 22, 24, the exterior
layers 28, 26 on the aluminum sheets 12, 14, the adhesive material
forming the adhesive core 16 is applied in two layers 18, 20, where
the adhesive layer 18 is applied to the intermediate layer 22 and
the adhesive layer 20 is applied to the intermediate layer 24. The
adhesive material may be applied, for example, by spraying or
rolling, and subjected to a drying operation, may be applied using
a hot melt or rolling method subjected to a curing operation such
as an ultraviolet (UV) cure, or may be applied as a dry adhesive
film. The applied adhesive material is wetted out, e.g.,
distributed, such that the adhesive material covers the entire
surface of the aluminum sheet 12, 14, e.g., is coextensive with the
surface of the aluminum sheet 12, 14, at a uniform coating
thickness sufficient to provide the thickness of the respective
adhesive layers 18, 20 required to provide desired thickness of the
adhesive core 16 after laminating and curing the laminate structure
100. The aluminum sheet 12, including the intermediate layer 22 and
the adhesive layer 18 sequenced as shown in FIG. 2, and the
aluminum sheet 14, including the intermediate layer 24 and the
adhesive layer 20 sequenced as shown in FIG. 2, are presented to
the laminating process, e.g., to laminating rolls such that the
adhesive layers 18, 20 are facing, e.g., are brought in contact
with each other, and laminated by applying a laminating pressure,
for example, via the laminating rolls, to form the laminate
structure 100. Alternately, as shown in FIG. 1 and previously
described herein, the adhesive material forming the adhesive core
16 may be applied in a single layer to one of the intermediate
layers 22, 24.
[0043] The laminate structure 100 is cured by elevating the
temperature of the aluminum sheets 12, 14 and the adhesive core 16,
for example, using one or more ovens, flame bars, heated lamination
rolls, etc. during and/or after the lamination process forming the
laminate structure 100. In one example, at presentation to the
laminating rolls and/or during application of the laminating
pressure to form the laminate structure 100, the aluminum sheets
12, 14 are maintained at approximately the same temperature to
minimize warpage of the laminate structure 100 by providing uniform
expansion and contraction of each of the aluminum sheets 12, 14
relative to the other of the aluminum sheets 12, 14. As used
herein, "approximately the same temperature" is defined as the
temperature of one of the aluminum sheets 12, 14 is maintained
within 100 degrees Fahrenheit, and preferably within 50 degrees
Fahrenheit, of the other of the aluminum sheets immediately prior
to and/or during lamination to equalize the residual thermal
stresses and/or thermal expansion and/or contraction of the
aluminum sheets 12, 14.
[0044] Following the lamination process, e.g., after laminating and
curing the sequenced layers forming the laminate structure 100, the
laminate structure 100 may be subjected to additional treatments,
including, as previously described herein, the application of one
or more of the exterior layers 26, 28, 34. The laminate structure
100 may be used to form components therefrom. For example, the
laminate structure 100 may be cut, stamped, pressed, bent,
extruded, punched, drilled, etc. to form a component, where the
component may define one or a combination of one or more bends,
fillets, chamfers, shoulders, openings, holes, slots, ribs,
flanges, hems, etc. By way of non-limiting example, the laminate
structure 100 may be used to form a variety of structural
components which may be used in vehicles, such as a dash panel,
package tray, panel shelf, seat panel, cowl panel, instrument panel
frame, floor panel, tunnel panel, wheel well, back-up panel, trunk
panel, etc. The examples are non-limiting, and it would be
understood that various components which may be structural or
non-structural components, may be formed using the laminate
structure 100 described herein.
[0045] The laminate structure 100 and/or a component formed
therefrom may be fastened to another component by use of various
means of attachment. In one example, an adhesive, such as a
structural adhesive, can be used to bond the laminate structure 100
and/or component formed therefrom to another component or
structure. The laminate structure 100 in this example may include
an exterior coating 26, 28 which is configured to passivate the
exterior surface of the aluminum sheet 12, 14 to which the
attaching adhesive is being applied and/or to contribute to the
bond strength of the bonded interface formed between the laminate
structure 100 and the attaching adhesive. In a non-limiting
example, the attaching adhesive may be an epoxy type structural
adhesive. In one example, the laminate structure 100 includes the
isolation layer 34 on the attachment surface, for example, to
prevent ion transfer via the attaching adhesive through the
isolation layer 34, where ion transfer may occur from a component,
such as a steel component, to which the laminate structure 100 is
attached, such that galvanic corrosion is prevented at the
attachment interface between the attaching adhesive and the
laminate structure 100.
[0046] In another example, a mechanical means of attachment, using
a fastener such as a rivet, bolt, clamping element, crimping
element, etc. may be used to fasten the laminate structure 100
and/or component formed therefrom to another component or
structure, where the fastener, e.g., the rivet, bolt, etc. is
attached via an opening, such as a hole or slot, formed in the
laminate structure 100, where the opening formed in the laminate
structure 100 to receive the fastener can include an edge surface
exposing the core layer 10 to the attaching fastener. By way of
non-limiting example, the fastener may be a rivet such as a pop
rivet, self-piercing rivet, Henrob.TM. rivet, blind rivet, etc. In
another example, the fastener may be a bolt, which may be a
standard bolt, a lock bolt, a Huck bolt, etc. In another example,
the fastener may be a clamping element or crimping element which is
tightened or distorted in contact with the laminate structure 100
to attach the laminate structure (or component formed therefrom) to
another component or structure, where the clamping or crimping
element may be tightened around a portion or the laminate structure
100 including but not limited to an edge portion of the laminate
structure 100.
[0047] As discussed for the adhesive means of attachment, the
laminate structure 100 may include an exterior coating 26, 28
and/or an isolation layer 34 to prevent corrosion of the laminate
structure 100 at the attachment interface between the laminate
structure 100 and the fastener and/or the attachment interface
between the laminate structure 100 and the attached component. The
fastener may be an aluminum fastener, a galvanized fastener, a
coated fastener, or otherwise treated or configured to prevent
corrosion of the laminate structure 100 at the attachment interface
between the fastener and the laminate structure. In one example,
the attached component may be a steel component which is placed in
contact with and/or abutted to the laminate structure 100, and
attached to the laminate structure 100 by the fastener. The
isolation layer 34 of the laminate structure 100 is disposed
between one of the aluminum sheets 12, 14 of the laminate structure
100 which is adjacent the steel structure to prevent ion transfer
from the steel component and/or to prevent galvanic corrosion of
the laminate structure 100. The laminate structure 100 may include
one or more auxiliary layers 30, 32, which may be configured, as
previously discussed herein, to prevent the ingress of corrosive
elements at an exposed edge of the laminate structure 100 in
contact with the fastener, and to prevent ingression of a
contaminant or corrosive elements into the bonded interface between
the adhesive core 16 and the aluminum layers 12, 14. For example,
the exposed edge of the laminate structure 100 may be an edge of
the laminate structure defining the opening to receive the
fastener, or an exposed edge of the laminate structure 100, such as
a cut edge or exterior edge of the component formed from the
laminate structure 100, to which a fastener such as a clamp or
crimping element may be attached.
[0048] In another example, the laminate structure 100 and/or
component formed therefrom may be attached to another component or
structure by welding, e.g, by forming a weld between the laminate
structure 100 and the component or structure to which the laminate
structure 100 is attached. In this example, the laminate structure
100 can be configured as shown in FIG. 4 as an electrically
conductive laminate structure 100. As previously discussed herein,
the electrically conductive laminate structure 100 includes core
layer 10 and/or adhesive core 16 which includes electrically
conductive filler particles 16 that are shaped, sized, and/or
dispersed within the adhesive core 16 to provide an electrically
conductive path through the adhesive core 16. In a preferred
example, the laminate structure 100 to be welded to another
component or structure includes an adhesive core 16 made of a
polymer based adhesive in which aluminum filler particles 36 are
dispersed. Preferably the aluminum filler particles 36 are shaped,
sized and dispersed in the adhesive core 16 such that the adhesive
core 16 has a conductivity substantially the same as the aluminum
sheets 12, 14, such that the resistivity of the laminate structure
100 is substantially uniform through its thickness and to prevent
expulsion of the adhesive core 16 from the laminate structure 100
during forming of the weld. The laminate structure 100 as described
in the present example is suitable for attachment by welding to
another component or structure using, for example, resistive spot
welding, cold metal transfer welding also known as cold metal
fusion welding, delta strip welding also known as continuous strip
welding, etc.
[0049] The illustrative examples provided by the description herein
and the related figures are non-limiting, and it would be
understood that a plurality of alternative configurations of the
layers of the laminate structure 100 exist within the scope of the
description incorporating various combinations of the metal sheets
10, 12, configurations of the core layer 10, various configurations
of the adhesive core 16, and various combinations and/or
configurations of one or more of intermediate layers 22, 24,
auxiliary layers 30, 32, exterior layers 26, 28, separating layers
34, and/or filler particles 36 to provide a laminate structure 100
characterized by a combination of properties and/or features as
required by the specified application and/or use of the laminate
structure 100 and/or a component formed therefrom. The combination
of properties and/or features for which a laminate structure 100 is
configured includes a combination of one or more of NVH properties,
damping, elongation, tensile strength, shear strength, formability,
peel strength, corrosion prevention, thermal properties, and/or
electrical conductivity. The example configurations of laminate
structures 100 shown in FIGS. 1-4 and the CLF behavior of the
laminate structures 100 represented by the CLF curves 44, 46, 48
are non-limiting, and it would be understood that the various
layers shown in the figures may be alternatively combined to
provide other configurations of the laminate structure 100 not
shown in the figures but included in the scope of the
description.
[0050] The detailed description and the drawings or figures are
supportive and descriptive of the present teachings, but the scope
of the present teachings is defined solely by the claims. While
some of the best modes and other embodiments for carrying out the
present teachings have been described in detail, various
alternative designs and embodiments exist for practicing the
present teachings defined in the appended claims.
* * * * *