U.S. patent application number 13/291046 was filed with the patent office on 2012-03-08 for armor system having ceramic matrix composite layers.
Invention is credited to John E. Holowczak.
Application Number | 20120055327 13/291046 |
Document ID | / |
Family ID | 45769697 |
Filed Date | 2012-03-08 |
United States Patent
Application |
20120055327 |
Kind Code |
A1 |
Holowczak; John E. |
March 8, 2012 |
ARMOR SYSTEM HAVING CERAMIC MATRIX COMPOSITE LAYERS
Abstract
An example armor system includes a first ceramic matrix
composite armor layer, a second ceramic matrix composite armor
layer, and a monolithic ceramic armor layer directly bonded to the
first and the second ceramic matrix composite armor layers.
Inventors: |
Holowczak; John E.; (S.
Windsor, CT) |
Family ID: |
45769697 |
Appl. No.: |
13/291046 |
Filed: |
November 7, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12039851 |
Feb 29, 2008 |
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13291046 |
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12100528 |
Apr 10, 2008 |
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12039851 |
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11682390 |
Mar 6, 2007 |
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12100528 |
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60794276 |
Apr 20, 2006 |
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61423811 |
Dec 16, 2010 |
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Current U.S.
Class: |
89/36.02 ;
89/906; 89/908; 89/917; 89/921; 89/930 |
Current CPC
Class: |
F41H 5/0414 20130101;
F41H 5/0428 20130101 |
Class at
Publication: |
89/36.02 ;
89/906; 89/908; 89/917; 89/921; 89/930 |
International
Class: |
F41H 5/04 20060101
F41H005/04 |
Goverment Interests
STATEMENT OF GOVERNMENT INTEREST
[0002] This invention was made with government support under
Contract No. W911QX-07-C-0077 awarded by the United States Army.
The Government has certain rights in this invention.
Claims
1. An armor system, comprising: a first ceramic matrix composite
armor layer; a second ceramic matrix composite armor layer; and a
monolithic ceramic armor layer directly bonded to the first and the
second ceramic matrix composite armor layers.
2. The armor system of claim 1, wherein a first side of the
monolithic ceramic armor layer is directly bonded to the first
ceramic matrix composite armor layer, and an opposing, second side
of the monolithic ceramic armor layer is bonded to the second
ceramic matrix composite armor layer.
3. The armor system of claim 1, wherein the armor system is free of
any polymer or metal-based adhesive between the monolithic ceramic
armor layer, the first ceramic matrix composite armor layer, and
the second ceramic matrix composite armor layer.
4. The armor system of claim 1, including a fibrous polymeric
backing layer directly bonded to the second ceramic matrix
composite armor layer.
5. The armor system of claim 1, wherein the first ceramic matrix
composite armor layer and the second ceramic matrix composite layer
include a monolithic ceramic material selected from silicon
nitride, silicon aluminum oxynitride, silicon carbide, silicon
oxynitride, aluminum nitride, aluminum oxide, hafnium oxide,
zirconia, siliconized silicon carbide, and boron carbide.
6. The armor system of claim 1, wherein the first ceramic matrix
composite armor layer, the second ceramic matrix composite armor
layer, or both the first and second ceramic matrix composite armor
layers comprise a ceramic matrix having a unidirectionally oriented
fibers disposed within the ceramic matrix.
7. The armor system of claim 6, wherein the unidirectionally
oriented fibers are located within a plurality of sublayers of the
ceramic matrix, and at least one of the plurality of sublayers
includes unidirectionally oriented fibers having a different
orientation than the unidirectionally oriented fibers of another of
the plurality of sublayers.
8. The armor system of claim 1, wherein the monolithic ceramic
armor layer comprises a silicon carbide.
9. The armor system of claim 8, wherein the silicon carbide is a
hot-pressed silicon carbide.
10. The armor system of claim 1, wherein the ceramic matrix
composite armor layers consist of a matrix comprised of an alkaline
earth aluminosilicate.
11. The armor system of claim 1, wherein the armor system is
configured to prevent a bullet from piercing the armor system, and
a thickness of the monolithic ceramic armor layer is generally 70
percent of a caliber of the bullet.
12. The armor system of claim 1, wherein the armor system is
configured to prevent a projectile from piercing the armor system,
and a thickness of the monolithic ceramic armor layer is between 60
percent and 85 percent of a diameter of the projectile.
13. The armor system of claim 12, wherein the armor system is
configured to prevent a projectile from piercing the armor system,
and a thickness of the monolithic ceramic armor layer is between 80
percent and 85 percent of a diameter of the projectile.
14. The armor system of claim 1, wherein the armor system is
disposed within an armor panel that is located in at least one of
portion of an armored vest or a vehicle.
15. The armor system of claim 1, wherein at least one of the first
or second ceramic matrix composite armor layers is a glass-ceramic
matrix composite armor layer.
16. An armor system, comprising: a first ceramic matrix composite
armor layer; a second ceramic matrix composite armor layer; a
monolithic ceramic armor layer having a first side and an opposing,
second side, the first side directly bonded to the first ceramic
matrix composite armor layer and free of any adhesive therebetween,
the second side directly bonded to the second ceramic matrix
composite armor layer and free of any adhesive therebetween; and a
fibrous polymeric backing layer directly bonded to the second
ceramic matrix composite armor layer.
17. The armor system of claim 16, wherein at least one of the first
or second ceramic matrix armor layer comprises a matrix consisting
of an alkaline earth aluminosilicate.
18. The armor system of claim 16, wherein the first ceramic matrix
composite matrix armor layer and the second ceramic matrix
composite armor layer each comprise a plurality of sub-layers that
each include a ceramic matrix and unidirectionally oriented fibers
disposed within the ceramic matrix, and at least one of the
plurality of sub-layers having a different orientation than another
of the sub-layers relative to the unidirectionally oriented
fibers.
19. A method of manufacturing an armor system, comprising: forming
a first glass-ceramic matrix composite armor layer on a first side
of a monolithic ceramic armor layer such that the first
glass-ceramic matrix composite armor layer is directly bonded to
the monolithic ceramic armor layer and free of any adhesive
therebetween; and forming a second glass-ceramic matrix composite
armor layer on an opposing, second side of the monolithic ceramic
armor layer such that the second glass-ceramic matrix composite
layer is directly bonded to the monolithic ceramic armor layer and
free of any adhesive therebetween, wherein the first and second
glass-ceramic matrix composite armor layers each comprise a ceramic
matrix and unidirectionally oriented fibers disposed within the
ceramic matrix.
20. The method of claim 19, including forming a polyethylene fiber
layer on a side of the second glass-ceramic matrix composite armor
layer.
21. The method of claim 19, wherein the matrix of the glass-ceramic
armor layers are comprised of an alkaline earth aluminosilicate.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S.
application Ser. No. 12/039,851, filed on 29 Feb. 2008, and Ser.
No. 12/100,528, filed on 10 Apr. 2008; both of which are
continuations-in-part of U.S. application Ser. No. 11/682,390,
filed 6 Mar. 2007, which claims priority to U.S. Provisional
Application No. 60/794,276. This application also claims priority
to U.S. Provisional Application No. 61/423,811, which was filed on
16 Dec. 2010. Each of these applications is incorporated herein by
reference.
BACKGROUND
[0003] This disclosure relates to an armor system and, more
particularly, to an armor system having multiple ceramic and
ceramic matrix composite layers and a method for manufacturing the
armor system.
[0004] A variety of configurations of projectile resistant armor
are known. Some are used on vehicles while others are specifically
intended to protect an individual. Some materials or material
combinations have proven useful for both applications. However,
there is a continuing need to provide armor systems with lower
aerial density, and methods of manufacturing armor systems that are
useful in a variety of different applications.
SUMMARY
[0005] An example armor system includes a first ceramic matrix
composite armor layer, a second ceramic matrix composite armor
layer, and a monolithic ceramic armor layer directly bonded to the
first and the second ceramic matrix composite armor layers without
the use of a polymer based adhesive.
[0006] Another example armor system includes a first ceramic matrix
composite armor layer, a second ceramic matrix composite armor
layer, and a monolithic ceramic armor layer. The monolithic layer
has a first side and an opposing, second side. The first side is
directly bonded to the first ceramic matrix composite armor layer
and free of any adhesive therebetween. The second side is directly
bonded to the second ceramic matrix composite armor layer and free
of any adhesive therebetween. A fibrous polymeric backing layer is
directly bonded to the second ceramic matrix composite armor layer.
The monolithic ceramic armor layer is silicon carbide in one
example.
[0007] An example method of manufacturing an armor system includes
forming a first ceramic matrix composite armor layer on a first
side of a monolithic ceramic armor layer such that the first
ceramic matrix composite armor layer is directly bonded to the
monolithic ceramic armor layer and free of any adhesive
therebetween. The method also includes forming a second ceramic
matrix composite armor layer on an opposing, second side of the
monolithic ceramic armor layer such that the second ceramic matrix
composite layer is directly bonded to the monolithic ceramic armor
layer and free of any adhesive therebetween. The first and second
ceramic matrix composite armor layers each comprise a ceramic
matrix and unidirectionally oriented fibers disposed within the
ceramic matrix.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The various features and advantages of this invention will
become apparent to those skilled in the art from the following
detailed description of the currently preferred embodiment. The
drawings that accompany the detailed description can be briefly
described as follows.
[0009] FIG. 1 illustrates an example armor system.
[0010] FIG. 2 illustrates a portion of an example ceramic matrix
composite armor layer having unidirectionally oriented fibers
disposed within a ceramic matrix.
[0011] FIG. 3 illustrates another example armor system.
[0012] FIG. 4 illustrates a 0.degree.//90.degree. ceramic matrix
composite armor layer.
[0013] FIG. 5 illustrates a 0.degree./45.degree./90.degree. ceramic
matrix composite armor layer.
[0014] FIG. 6 illustrates armored panels utilized within an armor
vest.
[0015] FIG. 7 illustrates an example method for manufacturing an
armor system.
DETAILED DESCRIPTION
[0016] FIG. 1 illustrates a portion of an example armor system 10
for resisting impact of a ballistic projectile. The armor system 10
may be utilized in a variety of different applications for
defeating ballistics, including, but not limited to, armor piercing
projectiles at various velocities. For example, the armor system 10
includes an aerial density that is at least equal to or lighter
than known armor systems and may be used as a plate or panel in a
personal body armor vest or vehicle.
[0017] The armor system 10 is a multilayer structure that includes
a monolithic ceramic armor layer 12, a ceramic matrix composite
armor layer 13, another ceramic matrix composite armor layer 14,
and a fibrous polymeric backing layer 15. It is to be understood
that the ceramic armor layer 12, the ceramic matrix composite armor
layers 13 and 14, and the fibrous polymeric backing layer 15 may
also be used in combination with other armor layers, depending upon
a particular design and intended use. The fibrous polymeric backing
layer 15 is secured to the ceramic matrix composite armor layer
14.
[0018] The armor system 10 is arranged relative to an expected
projectile direction 16. The ceramic matrix composite armor layer
13 includes a projectile strike face 18 for initially receiving a
projectile 17, such as a bullet, which has a diameter d. The
diameter d is a sometimes considered a caliber of the projectile
17. In this example, the diameter d is a measurement of the
projectile 17 in a direction aligned with the strike face 18.
[0019] The ceramic armor layer 12 and ceramic matrix composite
armor layers 13 and 14 may be any desired thickness or shape for
resisting a ballistic impact. In some examples, the thickness is
selected depending on the projectile 17. For example, the
monolithic ceramic armor layer 12 and ceramic matrix composite
armor layer 14 may be between several hundredths of an inch thick
and several inches thick, depending upon a particular design and
intended use of the armor system 10. In this example, the thickness
t of the monolithic ceramic armor layer 12 is about 70 percent of
the diameter d of the projectile 17. In another example, the
thickness t is between 60 percent and 85 percent of the diameter d.
In yet another example, the thickness t is between 80 percent and
85 percent of the diameter d. Further, in this example, the ceramic
matrix composite layer 14 is about three times thicker than the
ceramic matrix composite layer 13.
[0020] A front face 19 of the monolithic ceramic armor layer 12 is
bonded to the ceramic matrix composite layer 13. A back face 20 of
the ceramic armor layer 12, which opposes the front face 19, is
bonded to the ceramic matrix composite armor layer 14. Thus, the
ceramic armor layer 12 and the ceramic matrix composite armor
layers 13 and 14 are directly bonded to one another, as will be
described below, and do not necessarily include any layers of
adhesive that would add thickness and/or diminish the ballistic
impact performance of the armor system 10.
[0021] Using ceramic materials for the ceramic armor layer 12 and
the ceramic matrix composite armor layers 13 and 14 provides a
relatively close sound impedance match between the layers. Sound
impedance refers to the speed of sound through a given ceramic
layer of armor material. For example, an impact between a
projectile and the projectile strike face 18 of the ceramic armor
layer 12 causes compressive stress waves to move through the
ceramic matrix composite armor layer 13, the monolithic ceramic
armor layer 12, and the ceramic matrix composite armor layer 14
toward the back face 20. At least a portion of the compressive
stress wave reflects off of a front face 18 of the ceramic matrix
composite armor layer 13, a rear face 23 of the ceramic matrix
composite layer 13, the back face 20 of the ceramic layer 12, and a
rear face 24 of the ceramic matrix composite armor layer 14.
[0022] In prior art, the stress waves passing through the
monolithic ceramic encounters either an adhesive, or the polymer
matrix of a bonded polymer composite, at the backface. The sharp
change in impedance, orders of magnitude lower than the monolithic
ceramic, inherent in these polymer layers causes a high magnitude
reflected tensile wave to return through the ceramic. Because
monolithic ceramics are much weaker in tension than compression,
this reflected tensile wave results in extensive damage and
fracture.
[0023] In the embodiment of FIG. 1, the similar impedance of the
monolithic ceramic armor layer 12 and matrix of the ceramic matrix
composite layers 13 and 14 cause the incoming compressive pulse to
be transmitted as a compressive wave that is rapidly and
efficiently absorbed into ceramic matrix composite layers 13 or 14
which possess high work of fracture under tension and compression.
This provides more efficient energy absorption that captures a
greater fraction of the incoming compressive wave than in the prior
art polymer adhesive bonded and/or polymer matrix composite layered
armor.
[0024] Depending on the ceramic materials selected, the impedance
of each of the ceramic armor layer 12 and the ceramic matrix
composite armor layers 13 and 14 may be in the range of
10-40.times.10.sup.6 kilograms per square meter seconds
(kg/m.sup.2s). In a further example, the impedance may be in the
range of about 25-35.times.10.sup.6 kg/m.sup.2s.
[0025] In the disclosed embodiment, the ceramic armor layer 12 is a
monolithic ceramic material. More specifically, the ceramic armor
layer 12 is a material such as silicon carbide, or boron carbide.
The impedance of this material may be in the range of 15-20
kilograms per square meter seconds (kg/m.sup.2s), which is
relatively close to the impedance of the ceramic matrix composite
armor layers 13 and 14.
[0026] The term "monolithic" as used in this disclosure refers to a
single material; however, the single material may include
impurities that do not affect the properties of the material,
elements that are unmeasured or undetectable in the material, or
additives (e.g., processing agents or densification aides).
However, in other examples, the monolithic material may be pure and
free of impurities. Given this description, one of ordinary skill
in the art will understand that other oxides, carbides, nitrides,
or other types of ceramics may be used to suit a particular
need.
[0027] In the disclosed embodiment, the ceramic matrix composite
armor layers 13 and 14 are a composite material. FIG. 2 illustrates
a perspective view of the ceramic matrix composite armor layer 14,
which includes a ceramic matrix 34 and unidirectionally oriented
fibers 36 disposed within the ceramic matrix 34. That is, the
unidirectionally oriented fibers 36 are substantially parallel and
coplanar. The term "substantially" as used in this description
relative to geometry refers to possible variation in the given
geometry, such as typical manufacturing variation. The construction
of the example ceramic composite armor layer 13 is similar to the
construction of the ceramic composite armor layer 14 shown in FIG.
2.
[0028] The monolithic ceramic material of the ceramic armor layer
12 initially receives a ballistic projectile and absorbs a portion
of the energy associated with the ballistic projectile through
fracture and stress wave cancellation as described above. The
composite of the ceramic matrix composite armor layer 14 reflects a
portion of the stress waves as discussed above and absorbs a
portion of the energy associated with the ballistic projectile
through fiber debonding and pullout, as well as shear failure. The
composite also facilitates reduction in the degree of fragmentation
of the monolithic ceramic material compared to conventional backing
materials.
[0029] In the disclosed examples, the unidirectionally oriented
fibers 36 facilitate energy absorption and reflection of stress
waves due to the ballistic impact. For example, during a ballistic
event, interwoven fibers that are bent around each other must first
straighten out prior to absorbing large levels of strain energy.
The time that it takes for the bent fibers to straighten may
increase the ballistic response time. However, the unidirectionally
oriented fibers 36 are already straight and therefore do not
require additional time for straightening as do interwoven fibers.
Thus, using the unidirectionally oriented fibers 36 facilitates
reduction of the reaction time of the ceramic armor composite layer
14 or in a ballistic event.
[0030] As will now be described, the ceramic matrix 34 and
unidirectionally oriented fibers 36 of the ceramic matrix composite
armor layers 13 and 14 may include a variety of different types of
materials, which may be selected depending on a particular intended
use. The selected materials are a ceramic matrix composite, a glass
matrix composite, or some combination of these. For example, the
unidirectionally oriented fibers 36 may be silicon carbide fibers,
silicon nitride fibers, silicon-oxygen-carbon fibers,
silicon-nitrogen-oxygen-carbon fibers, aluminum oxide fibers,
silicon aluminum oxynitride fibers, aluminum nitride fibers, or
carbon fibers. In some examples, the unidirectionally reinforced
fibers 36 include fibers of NICALON.RTM., SYLRAMIC.RTM.,
TYRANNO.RTM., HPZ.TM., pitch derived carbon, or polyacronitrile
derived carbon, fibers. Notably, these materials are not polymer
matrix composite materials.
[0031] The ceramic matrix 34 may include a silicate glass material,
such as magnesium aluminum silicate, magnesium barium silicate,
lithium aluminum silicate, borosilicate, or barium aluminum
silicate. Given this description, one of ordinary skill in the art
will understand that other types of fibers and matrix materials may
be used to suit a particular need.
[0032] As can be appreciated, the ceramic matrix composite armor
layers 13 and 14 of FIG. 2 are each a single layer. In another
embodiment illustrated in FIG. 3, like elements are represented
with like reference numerals and modified elements are represented
with the addition of a prime symbol. In this embodiment, an armor
system 10' includes ceramic matrix composite armor layers 13' and
14' each having a plurality of sublayers 38. Each of the sublayers
38 includes unidirectionally oriented fibers 36' disposed within a
matrix 34', similar to the single layer of the ceramic matrix
composite armor layers 13 and 14 of the previous example. Using
multiple sublayers 38 may facilitate even greater energy
absorption.
[0033] Each of the sublayers 38 may have an associated orientation
relative to the unidirectionally oriented fibers 36' of the
respective sublayer 38. In this regard, the unidirectionally
oriented fibers 36' of the sublayers 38 may be arranged with
different orientations to facilitate uniform energy absorption and
reflection, for example. For instance, for illustrative purposes
only, FIG. 4 illustrates only the unidirectionally oriented fibers
36' of two of the sublayers 38. Unidirectionally oriented fibers
36' of one of the sublayers 38 are oriented in a 0.degree.
orientation as represented by axis 40 and unidirectionally oriented
fibers 36' of another of the sublayers 38 are oriented 90.degree.
as represented by axis 44 relative to the 0.degree. orientation 40.
That is, the sublayers 38 provide a 0.degree./90.degree.
arrangement. As can be appreciated, the other sublayers 38
(including the sublayers 38 of the ceramic matrix composite layer
13') may be likewise oriented.
[0034] In the disclosed example, six of the sublayers 38 are used
in each of the ceramic matrix composite layers 13' and 14';
however, fewer or more sublayers 38 may be used.
[0035] As can be appreciated, other orientations among the
sublayers 38 may be used. FIG. 5 illustrates another example in
which the unidirectionally oriented fibers 36' of one of the
sublayers 38 are oriented in a 0.degree. orientation as represented
by axis 46, unidirectionally oriented fibers 36' of another
sublayer 38 are oriented at a +45.degree. orientation as
represented by axis 48 relative to the 0.degree. orientation 46,
unidirectionally oriented fibers 36' of another sublayer 38 are
oriented at a -45.degree. orientation as represented by axis 50
relative to the 0.degree. orientation 46, and unidirectionally
oriented fibers 36' of another sublayer 38 are oriented at a
90.degree. orientation as represented by axis 52 relative to the
0.degree. orientation 46 (overall, a
0.degree./+45.degree./-45.degree./90.degree. arrangement). Given
this description, one of ordinary skill in the art will be able to
recognize other orientations among the sublayers 38 to meet their
particular needs.
[0036] Referring to FIG. 6, the armor system 10 or 10' may be
formed into panels 54 that are located within an armored vest 56.
The panels 54 may be configured as small arms protective inserts
(SAPI), which are removably retained at the front and the back of
the armored vest 56. However, it is to be understood that the
panels 54 may be sized to fit within current personal body armor
system such as the interceptor body armor system. Additionally, the
panels 54 may be adapted for use in other wearable armor systems
for protecting an individual's side, neck, throat, shoulder, or
groin areas.
[0037] FIG. 7 illustrates one example method for manufacturing the
armor system 10 or 10' into the shape of the panels 54 disclosed
herein, or into other desired shapes. The manufacturing method 78
generally includes forming the ceramic matrix composite armor
layers 13, 13', 14 or 14' using pre-impregnated unidirectionally
oriented tape, although the disclosed armor systems 10 and 10' are
not limited to this manufacturing process and may be manufactured
using other techniques.
[0038] The pre-impregnated unidirectionally oriented tape includes
unidirectionally oriented fibers 36 or 36' that are disposed within
a glass-ceramic matrix particles 34 or 34' before consolidation.
That is, the ceramic matrix 34 or 34' includes ceramic particles of
the material selected for use as the ceramic matrix 34 or 34'
suspended in a binder, such as a polymeric binder.
[0039] The tape may be prepared from a slurry of the glass-ceramic
particles in a carrier fluid, such as a solvent, and infiltrated
into a fiber tow of the unidirectionally oriented fibers 36 or 36'.
The infiltrated unidirectionally oriented fibers 36 or 36' may then
be dried to remove the carrier fluid from the slurry and thereby
produce the pre-impregnated unidirectionally oriented tape.
[0040] Subsequently, the tape may be cut into sections and, in
lay-up action 80, stacked with a desired orientation of the
unidirectionally oriented fibers 36'. For the ceramic matrix
composite armor layer 14 that utilizes only a single layer, only a
single ply of the tape would be used. In a removal action 82, the
binder is removed from the ceramic particles, such as by heating
the tape at predetermined temperatures for predetermined amounts of
time. The remaining green state composite is then consolidated in a
consolidation action 84 at a predetermined temperature for a
predetermined amount of time to produce the ceramic matrix
composite armor layers 13, 13', 14 or 14'.
[0041] In the disclosed embodiment, the glass-ceramic matrix
composite armor layers 13, 13', 14 or 14' are consolidated or
otherwise formed directly on the ceramic armor layer 12, which is
pre-fabricated in a prior process. Forming the ceramic matrix
composite armor layers 13, 13', 14 or 14' directly on the ceramic
armor layer 12 facilitates providing a strong bond between the
ceramic armor layer 12 and the matrix 34 or 34' of the ceramic
matrix composite armor layers 13, 13', 14 or 14'. The relatively
strong bonding may facilitate transmission of stress waves and
absorption of energy as discussed above. For example, the ceramic
matrix 34 or 34' may chemically bond to the ceramic monolithic
material of the ceramic armor layer 12. However, it is to be
understood that any chemical bonding that may occur is not fully
understood and may also comprise other reactions or mechanical
interactions between the ceramic materials. In some examples, the
consolidation action 84 of the example manufacturing method 78 may
include other actions as disclosed in co-pending application Ser.
No. 12/039,851.
[0042] Although a combination of features is shown in the
illustrated examples, not all of them need to be combined to
realize the benefits of various embodiments of this disclosure. In
other words, a system designed according to an embodiment of this
disclosure will not necessarily include all of the features shown
in any one of the Figures or all of the portions schematically
shown in the Figures. Moreover, selected features of one example
embodiment may be combined with selected features of other example
embodiments.
[0043] The preceding description is exemplary rather than limiting
in nature. Variations and modifications to the disclosed examples
may become apparent to those skilled in the art that do not
necessarily depart from the essence of this disclosure. Thus, the
scope of legal protection given to this disclosure can only be
determined by studying the following claims.
* * * * *