Note: Descriptions are shown in the official language in which they were submitted.
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WO 99/60327 PCT/1L99/00260
COMPOSITE ARMOR PLATE
The present invention relates to composite armor plates and panels. More
particularly, the invention relates to an armored plate which may be worn to
provide
the user with lightweight ballistic protection, as well as to armored plates
for
providing ballistic protection for light and heavy mobile equipment and
vehicles
against high-speed projectiles or fragments.
In US patent 5,763,813 there is described a composite armor plate for
absorbing and dissipating kinetic energy from high velocity, armor-piercing
projectiles, said plate comprising a single internal layer of high density
ceramic
pellets which are directly bound and retained in plate form by a solidified
material
such that the pellets are bound in a plurality of superposed rows,
characterized in
that the pellets have an AIz03 content of at least 85%, preferably at least
93%, and
a specific gravity of at least 2.5, the majority of the pellets each have at
least one
axis in the range of about 3-12 mm, and are bound by said solidified material
in a
single internal layer of superposed rows, wherein a majority of each of said
pellets
is in direct contact with at least 4 adjacent pellets, the total weight of
said plate
does not exceed 45 kg/m2 and said solidified material and said plate are
elastic.
In European patent application Serial No. 98301769.0 there is described and
claimed a composite armor plate for absorbing and dissipating kinetic energy
from
high velocity, armor-piercing projectiles, said plate comprising a single
internal
layer of high density ceramic pellets which are directly bound and retained in
plate
form by a solidified material such that the pellets are bound in a plurality
of adjacent
rows, characterized in that the pellets have an AI203 content of at least 93%
and a
specific gravity of at least 2.5, the majority of the pellets each have at
least one axis
of at least 12 mm length and are bound by said solidified material in a single
internal layer of adjacent rows, wherein a majority of each of said pellets is
in direct
contact with at least 4 adjacent pellets, and said solidified material and
said plate
are elastic.
In WO-A-98/15796 there is described and claimed a ceramic body for
deployment in a composite armor panel, said body being substantially
cylindrical in
shape, with at least one convexly curved end face, wherein the ratio DIR
between
CA 02331529 2005-06-27
7
the diameter D of said cylindrical body and the radius R of curvature of said
at least
one convexly curved end face is at least 0.64:1.
There are four main considerations concerning protective armor panels. The
first consideration is weight. Protective armor for heavy but mobile military
equipment, such as tanks and large ships, is known. Such armor usually
comprises
a thick layer of alloy steel, which is intended to provide protection against
heavy
and explosive projectiles. However, reduction of weight of armor, even in
heavy
equipment, is an advantage since it reduces the strain on all the components
of the
vehicle. Furthermore, such armor is quite unsuitable for light vehicles such
as
automobiles, jeeps, light boats, or aircraft, whose performance is compromised
by
steel panels having a thickness of more than a few millimeters, since each
millimeter of steel adds a weight factor of 7.8 kglm2.
Armor for light vehicles is expected to prevent penetration of bullets of any
type, even when impacting at a speed in the range of 700 to 1000 meters per
second. However, due to weight constraints if is difficult to protect light
vehicles
from high caliber armor-piercing projectiles, e.g. of 12.7 and 14.5 mm, since
the
weight of standard armor to withstand such projectile is such as to impede the
mobility and performance of such vehicles.
A second consideration is cost. Overly complex armor arrangements,
particularly those depending entirely on synthetic fif~ers, can be responsible
for a
notable proportion of the total vehicle cost, and can make its manufacture
non-profitable.
A third consideration in armor design is compactness. A thick armor panel,
including air spaces between its various layers, increases the target profile
of the
vehicle. In the case of civilian retrofitted armored automobiles which are
outfitted
with internal armor, there is simply no room for a thick panel in most of the
areas
requiring protection.
A fourth consideration relates to ceramic plates used for personal and light
vehicle armor, which plates have been found to be vulnerable to damage from
mechanical impacts caused by rocks, falls, etc.
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3
Fairly recent examples of armor systems are described in U.S. Patent
No. 4,836,084, disclosing an armor plate composite including a supporting
plate
consisting of an open honeycomb structure of aluminium; and U.S. Patent
No.4,868,040, disclosing an antiballistic composite armor including a
shock-absorbing layer. Also of interest is U.S. Patent 4,529,640, disclosing
spaced
armor including a hexagonal honeycomb core member.
Other armor plate panels are disclosed in British Patents 1,081,464;
1,352,418; 2,272,272, and in U.S. Patent 4,061,815 wherein the use of sintered
refractory material, as well as the use of ceramic materials, are described.
Ceramic materials are nonmetallic, inorganic solids having a crystalline or
glassy structure, and have many useful physical properties, including
resistance to
heat, abrasion and compression, high rigidity, low weight in comparison with
steel,
and outstanding chemical stability. Such properties have long drawn the
attention
of armor designers, and solid ceramic plates, in thicknesses ranging from 7
mm. for
personal protection to 30 mm. for heavy military vehicles, are commercially
available for such use.
Much research has been devoted to improving the low tensile and low
flexible strength and poor fracture toughness of ceramic materials; however,
these
remain the major drawbacks to the use of ceramic plates and other large
components which can crack andlor shatter in response to the shock of an
incoming projectile.
Light-weight, flexible armored articles of clothing have also been used for
many decades, for personal protection against fire-arm projectiles and
projectile
splinters. Examples of this type of armor are found in U.S. Patent No.
4,090,005.
Such clothing is certainly valuable against low-energy projectiles, such as
those
fired from a distance of several hundred meters, but fails to protect the
wearer
against high-velocity projectiles originating at closer range and especially
does not
protect against armor-piercing projectiles. If made to provide such
protection, the
weight andlor cost of such clothing discourages its use. A further known
problem
with such clothing is that even when it succeeds in stopping a projectile the
user
may suffer injury due to indentation of the vest into the body, caused by too
small a
body area being impacted and required to absorb the energy of a bullet.
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WO 99160327 PCT/IL99/00260
4
A common problem with prior art ceramic armor concerns damage inflicted
on the armor structure by a first projectile, whether stopped or penetrating.
Such
damage weakens the armor panel, and so allows penetration of a following
projectile, impacting within a few centimeters of the first.
The present invention is therefore intended to obviate the disadvantages of
prior art ceramic armor, and in a first embodiment to provide an armor plate
which
is effective against small-caliber fire-arm projectiles, yet is of light
weight, i.e,
having a weight of less than 45 kg/m2 (which is equivalent to about 9 Ibslft2)
and
low bulk.
In other embodiments the present invention provides an armor plate which is
effective against a full range of armor-piercing projectiles from 5.56 mm and
even
up to 30 mm, as well as from normal small-caliber fire-arm projectiles, yet is
of light
weight, i.e., having a weight of less than 185 kglm2 , even for the heavier
armor
provided for dealing with 25 and 30 mm projectiles.
A further object of the invention is to provide an armor plate or panel which
is
particularly effective in arresting a plurality of armor-piercing projectiles
impacting
upon the same general area of the panel.
The armor plates described in US Patent 5,763,813 and European
application 98301769.0 are made using ceramic pellets made substantially
entirely
of aluminum oxide. In WO-A-98115796 the ceramic bodies are of substantially
cylindrical shape having at least one convexly-curved end-face, and are
preferably
made of aluminium oxide.
However, it has now been found that the improved properties of the plates
described in the above patent applications is as much a function of the
configuration of the pellets, which are of regular geometric form (for
example, the
pellets may be spherical or ovoidal, or of regular geometric cross-section,
such as
square, hexagonal, octagonal, or circular), said panels and their arrangement
as a
single internal layer of pellets bound by an elastic solidified material,
wherein each
of a majority of said pellets is in direct contact with at least four adjacent
pellets in
the same layer to provide mutual lateral confinement therebetween. As a
result,
composite armor plates superior to those available in the prior art can be
manufactured using glass pellets which have a specific gravity of only 2, or
pellets
CA 02331529 2000-11-08
EPp _ pG 1
13. 03. 2000
made of sintered refractory materials or ceramic materials having a
specif~avity
equal to or below that of aluminium oxide, e.g., boron carbide with a specific
gravity
of 2.45, silicon carbide with a specific gravity of 3.2 and silicon aluminum
oxynitride
with a speck gravity of about 3.2.
Thus, sintered oxides, nitrides, carbides and borides of magnesium, zirconium,
tungsten, molybdium, titanium and silica can be used and especially preferred
for
use in the present invention are pellets selected from the group consisting of
glass,
boron carbide, titanium diboride, silicon carbide, magnesium oxide, silicon
aluminum
oxynitride in both its alpha and beta forms and mixtures thereof.
With increase in speck gravity the stopping power of the plates increases so
that those plates utilizing pellets of higher specific gravity are also useful
for
absorbing and dissipating kinetic energy from high-velocity armor-piercing
bullets.
Accordingly, the present invention provides for absorbing and dissipating
kinetic energy from high velocity projectiles, said plate comprising a single
internal
layer of pellets which are directly bound and retained in plate form by a
solidified
material such that the pellets are bound in a plurality of adjacent rows,
characterized
in that the pellets have a speck gravity of at least 2 and are made of a
material
selected from the group consisting of glass, sintered refractory material and
ceramic
material other than aluminium oxide, the majority of the pellets each having
at least
one axis of at least 3 mm length and being bound by said solidified material
in said
single internal layer of adjacent rows such that each of a majority of said
pellets is in
direct contact with six adjacent pellets in the same layer to provide mutual
lateral
confinement therebetween, said pellets each having a major axis and a
substantially
regular geometric form with at least one convexly-curved end face, wherein
said
pellets are arranged with their major axes substantially parallel to each
other and
oriented substantially perpendicularly relative to an outer impact-receiving
major
surface of said plate, wherein said pellets are other than cylindrical bodies
having at
least one convexly-curved end face and said solidified material and said plate
are
elastic.
In preferred embodiments of the present invention there is provided a
composite armor plate for absorbing and dissipating kinetic energy from high
velocity projectiles, said plate comprising a single internal layer of pellets
which are
directly bound and retained in plate form by a solidified material such that
the pellets
AMENDED SHEET
CA 02331529 2000-11-08
6
are bound in a plurality of adjacent rows, characterized in that the pellets
have a
specific gravity of at least 2 and are made of a ceramic material having an
aluminium oxide content of not more than 80%, the majority of the pellets each
having at Least one axis of at least 3 mm length and being bound by said
solidified
material in said single internal layer of adjacent rows such that each of a
majority of
said pellets is in direct contact with six adjacent pellets in the same layer
to provide
mutual lateral confinement therebetween, said pellets each having a major axis
and
a substantially regular geometric form with at least one convexly-curved end
face,
wherein said pellets are arranged with their major axes substantially parallel
to each
other and oriented substantially perpendicularly relative to an outer impact-
receiving
major surface of said plate, wherein said pellets are other than cylindrical
bodies
having at least one convexly-curved end face and said solidified material and
said
plate are elastic.
Another way of expressing this aspect of the present invention is that the
present invention provides a composite armor plate for absorbing and
dissipating
kinetic energy from high velocity projectiles, said plate comprising a single
internal
layer of pellets which are directly bound and retained in plate form by a
solidfied
material such that the pellets are bound in a plurality of adjacent rows,
characterized
in that the pellets have a specific gravity of at least 2 and are made of a
material
selected from the group consisting of glass, sintered refractory material, and
ceramic material which does not contain aluminium oxide, the majority of the
pellets
each have at least one axis of at least 3 mm length and are bound by said
solidified
material in said single internal layer of adjacent rows such that each of a
majority of
said pellets is in direct contact with six adjacent pellets in the same layer
to provide
mutual lateral confinement therebetween, said pellets have a substantially
regular
geometric form and said solidified material and said plate are elastic, said
pellets
each having a major axis, said axes being substantially parallel to each other
and
substantially perpendicular relative to an outer impact-receiving major
surface of the
plate, each pellet having a non-circular cross-section and having a convexly
curved
end face orientated to substantially face in the direction of said major
surface.
As stated hereinbefore, in WO A-98/15796 there is described and claimed a
ceramic body for deployment in a composite armor panel, said body being
substantially cylindrical in shape, with at least one convexly curved end
face,
AMENDED SHEET
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6a
wherein the ratio D/R between the diameter D of said cylindrical body and the
radius
R of curvature of said at least one convexly curved end face is at
least 0.64:1 however, as noted, the entire thrust of said spec~cation is the
use of
cylindrical pellets having a speck diameter to radius ratio and therefore said
publication neither teaches nor suggests and it is not obvious therefrom that
pellets
of other geometric shape in direct contact with six adjacent pellets in the
same
internal layer to provide mutual~ lateral confinement therebetween would also
possess improved properties.
In yet another preferred embodiment of the present invention there is
provided a composite armor plate for absorbing and dissipating kinetic energy
from
high velocity projectiles, said plate comprising a single internal layer of
pellets which
are directly bound and retained in plate form by a solidified material such
that the
pellets are bound in a plurality of adjacent rows, characterized in that the
pellets
have a speck gravity of at least 2 and are made of a material selected from
the
group consisting of glass, sintered refractory material and ceramic material
other
than aluminium oxide, the majority of the pellets each having at least one
axis of at
least 3 mm length and being bound by said solidified material in said single
internal
layer of adjacent rows such that each of a majority of said pellets is in
direct contact
with six adjacent pellets in the same layer to provide mutual lateral
confinement
therebetween, said pellets being spherical and said solidified material and
said plate
being elastic.
In some preferred embodiments of the invention the majority of the pellets
each have at least one axis having a length in the range of about 6-19 mm, and
the
total weight of said plate does not exceed 45 kg/m2
In other preferred embodiments of the invention the majority of said pellets
each have at least one axis having a length in the range of from about 20 to
75 mm
and the weight of said plate does not exceed 185 kglm2.
In especially preferred embodiments said pellets are other than cylindrical
bodies having at least one convexly curved end face, wherein the ratio DIR
between
the diameter D of said cylindrical body and the radius R of curvature of said
at least
one convexly curved erid face is at least 0.64:1.
AMENDED SHEET
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6b
As indicated hereinbefore, preferably said pellets are made of a material
selected from the group consisting of nitrides, carbides and bonides of silica
and
boron.
The solid~ed material can be any suitable material which retains elasticity
upon hardening at the thickness used, such as aluminium, epoxy, a
thermoplastic
polymer such as polycarbonate, or a thermoset plastic, thereby allowing
curvature
of the plate without cracking to match curved surfaces to be protected,
including
body surfaces, as well as elastic reaction of the plate to incoming
projectiles to allow
increased contact force between adjacent pellets at the point of impact.
In French Patent 2,711,782, there is described a steel panel reinforced with
ceramic materials; however, due to the rigidity and lack of elasticity of the
steel of
said panel, said panel does not have the ability to deflect armor piercing
projectiles
unless a thickness of about 8-9 mm of steel is used, which adds undesirable
excessive weight to the panel and further backing is also necessary thereby
further
increasing the weight thereof.
It is further to be noted that the elasticity of the material used in prefen~d
embodiments of the present invention serves, to a certain extent, to increase
the
AMENDED SHEET
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7
probability that a projectile will simultaneously impact several pellets,
thereby
increasing the efficiency of the stopping power of the plate of the present
invention.
According to a further aspect of the invention, there is provided a
multi-layered armor panel, comprising an outer, impact-receiving layer formed
by a
composite armor plate as hereinbefore defined for deforming and shattering an
impacting high velocity projectile; and an inner layer adjacent to said outer
layer
and, comprising an elastic material for absorbing the remaining kinetic energy
from
said fragments. Said elastic material will be chosen according to cost and
weight
considerations and can be made of any suitable material, such as aluminium,
titanium or woven or non-woven textile material.
In especially preferred embodiments of the multi-layered armor panel, the
inner layer adjacent to said outer layer comprises a tough woven textile
material for
causing an asymmetric deformation of the remaining fragments of said
projectile
and for absorbing the remaining kinetic energy from said fragments, said
multi-layered panel being capable of stopping three projectiles fired
sequentially at
a triangular area of said multi-layered panel, wherein the height of said
triangle is
substantially equal to three times the length of the axis of said pellets.
As described, e.g., in U.S. Patent 5,361,678, composite armor plate
comprising a mass of spherical ceramic balls distributed in an aluminium alloy
matrix is known in the prior art. However, such prior art composite armor
plate
suffers from one or more serious disadvantages, making it difficult to
manufacture
and less than entirely suitable for the purpose of defeating metal
projectiles. More
particularly, in the armor plate described in said patent, the ceramic balls
are
coated with a binder material containing ceramic particles, the coating having
a
thickness of between 0.76 and 1.5 and being provided to help protect the
ceramic
cores from damage due to thermal shock when pouring the molten matrix material
during manufacture of the plate. However, the coating serves to separate the
harder ceramic cores of the balls from each other, and will act to dampen the
moment of energy which is transferred and hence shared between the balls in
response to an impact from a bullet or other projectile. Because of this and
also
because the material of the coating is inherently less hard than that of the
ceramic
cores, the stopping power of a plate constructed as described in said patent
is not
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WO 99/6032? PCT/IL99/00260
8
as good, weight for weight, as that of a plate in accordance with the present
invention, in which each of the pellets is in direct contact with at least
four and
preferably six adjacent pellets.
U.S. Patent 3,705,558 discloses a lightweight armor plate comprising a layer
of ceramic balls. The ceramic balls are in contact with each other and leave
small
gaps for entry of molten metal. In one embodiment, the ceramic balls are
encased
in a stainless steel wire screen; and in another embodiment, the composite
armor is
manufactured by adhering nickel-coated alumina spheres to an aluminium alloy
plate by means of a polysulfide adhesive. A composite armor plate as described
in
this patent is difficult to manufacture because the ceramic spheres may be
damaged by thermal shock arising from molten metal contact. The ceramic
spheres
are also sometimes displaced during casting of molten metal into interstices
between the spheres.
In order to minimize such displacement, U.S. Patents 4,534,266 and
4,945,814 propose a network of interlinked metal shells to encase ceramic
inserts
during casting of molten metal. After the metal solidifies, the metal shells
are
incorporated into the composite armor. It has been determined, however, that
such
a network of interlinked metal shells substantially increases the overall
weight of
the armored panel and decreases the stopping power thereof.
It is further to be noted that U.S. Patent 3,705,558 suggests and teaches an
array of ceramic balls disposed in contacting pyramidal relationship, which
arrangement also substantially increases the overall weight of the armored
panel
and decreases the stopping power thereof, due to a billiard-like effect upon
impact.
In U.S. Patents 3,523,057 and 5,134,725 there are described further
armored panels incorporating ceramic and glass balls; however, said panels are
flexible and it has been found that the flexibility of said panels
substantially reduces
their stopping strength upon impact, since the force of impact itself causes a
flexing
of said panels and a reduction of the supporting effect of adjacent
constituent
bodies on the impacted constituent body, due to the arrangement thereof in
said
patent. Thus, it will be noted that the teachings of U.S. Patent 5,134,725 is
limited
to an armor plate having a plurality of constituent bodies of glass or ceramic
material which are arranged in at least two superimposed layers, which
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WO 99/60327 PCT/1 L99/00260
9
arrangement is similar to that seen in US Patent 3,705,558. In addition,
reference to
Figures 3 and 4 of said patent show that pellets of a first Payer do not
contact pellets
of the same layer and are only in contact with pellets of an adjacent layer
and
therefore do not benefit from the support of adjacent pellets in the same
layer to
provide mutual lateral confinement of the pellets, as taught in the present
invention.
As will be realized, none of said prior art patents teaches or suggests the
surprising and unexpected stopping power of a single layer of ceramic or glass
pellets in direct contact with each other which, as will be shown hereinafter,
successfully prevents penetration of fire-arm projectiles despite the relative
light
weight of the plate incorporating said pellets.
Thus, it has been found that the novel armor of the present invention traps
incoming projectiles between several pellets which are held in a single layer
in
mutual abutting and laterally-confining relationship. The relatively moderate
size of
the pellets ensures that the damage caused by a first projectile is localized
and
does not spread to adjoining areas, as in the case of ceramic plates.
A major advantage of the novel approach provided by the present invention
is that it enables the fabrication of different plates and panels adapted to
deal with
different challenges, wherein e.g. smaller glass, sintered refractory or
ceramic
pellets can be used for personal armor and for meeting the challenge of 5.56,
7.62
and 9 mm projectiles, while larger ceramic pellets can be used to deal with
foreseen
challenges presented by 14.5 mm, 25 mm and even 30 mm armor piercing
projectiles.
Thus it was found that cylindrical pellets having a diameter of 9.5 mm and a
height of between 9.5 and 11.6 mm, as well as cylindrical pellets having a
diameter
of 12.7 mm and a height of between 9.5 and 11.6 mm were more than adequate to
deal with projectiles of between 5.56 and 9 mm, when arranged in a plate
according
to the present invention.
Similarly and as demonstrated hereinafter, spherical glass pellets having a
diameter of 10 mm were more than adequate to deal with multi-impacts of soft
metal
component 5.56 and 7.62 mm projectiles.
For heavy armored vehicles ceramic pellets having a diameter of 38 mm and
a height of between 32 and 75 mm were found to be more than adequate to deal
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WO 99/60327 PCT/IL99/00260
with 20, 25 and even 30 mm armor piercing projectiles when used in a multi-
layered
armor panel according to the present invention.
An incoming projectile may contact the pellet array in one of three ways:
1. Center contact. The impact allows the full volume of the pellet to
participate
in stopping the projectile, which cannot penetrate without pulverizing the
whole
pellet, an energy-intensive task. The pellets used are either spheres or other
regular geometric shapes having at least one convexly-curved end face, said
end
face being oriented to substantially face in the direction of an outer impact
receiving
major surface of said plate and this form, when supported in a matrix of
pellets, as
shown, e.g. in the figures attached hereto, has been found to be significantly
better
at resisting shattering than other pellet arrangements suggested in the prior
art.
2. Flank contact. The impact causes projectile yaw and shattering, thus
making projectile arrest easier, as a larger frontal area is contacted, and
not only
the sharp nose of the projectile. The projectile is deflected sideways and
needs to
form for itself a large aperture to penetrate, thus allowing the armor to
absorb the
projectile energy.
3. Valley contact. The projectile is jammed, usually between the flanks of
three pellets, all of which participate in projectile arrest. The high side
forces
applied to the pellets are resisted by the pellets adjacent thereto as held by
the
matrix, and penetration is prevented.
An additional preferred embodiment according to the present invention is one
wherein the ceramic material is SiAION in its alpha structure of
Sis_ZAIZOZNB.Z, in
which "z" is a substitution coefficient of AI and 0 in the Si3N4 and the "beta
structure" of the formula Me~,~e~Si,z-~m+~>Alm+nOnN,s.~, wherein Me is a metal
such as
Li, Mg, Ca, Y, and lanthanide's, m and n are substitution coefficients and val
is the
valency of the metal. .
The invention will now be described in connection with certain preferred
embodiments with reference to the following illustrative figures so that it
may be
more fully understood.
With reference now to the figures in detail, it is stressed that the
particulars
shown are by way of example and for purposes of illustrative discussion of the
preferred embodiments of the present invention only, and are presented in the
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11
cause of providing what is believed to be the most useful and readily
understood
description of the principles and conceptual aspects of the invention. In this
regard,
no attempt is made to show structural details of the invention in more detail
than is
necessary for a fundamental understanding of the invention, the description
taken
with the drawings making apparent to those skilled in the art how the several
forms
of the invention may be embodied in practice.
In the drawings;
Fig. 1 is a cross-sectional side view of a first preferred embodiment of a two-
layered
armor panel according to the invention;
Figs. 2 is a perspective view of a small section of a second preferred
embodiment
of an armor panel according to the invention;
There is seen in Fig. 1 a composite armor plate 10 for absorbing and
dissipating kinetic energy from fire-arm projectiles 12, said plate comprising
a
single internal layer of spherical glass pellets 14, said pellets being
arranged in a
single layer of adjacent rows, wherein each of a majority of said pellets is
in direct
contact with at least 4 adjacent pellets (as better seen with regard to the
pellets
shown in Fig. 2). As seen, the entire array of pellets is bound in said single
layer of
a plurality of adjacent rows by solidified epoxy 16 and said plate 10 is
further
provided with an
inner backing layer 18 made of DYNEEMA~ or of similar material, to form a
multi-layered armored panel 20.
There is seen in Fig. 2 a composite armor plate 22 for absorbing and
dissipating kinetic energy from fire-arm projectiles 12, said plate comprising
a
single internal layer of glass pellets 24 which are substantially cylindrical
with at
least one convexly-curved end face, said pellets being arranged in a single
layer of
adjacent rows wherein each of a majority of said pellets 24' is in direct
contact with
at least 4 adjacent pellets 24". As shown, the entire array of pellets is
bound in said
single layer of a plurality of adjacent rows by solidified epoxy 16, and said
plate 22
is further provided with an inner backing layer 18 made of DYNEEMA~ or of
similar
textile material such a backing made of polycarbonate, to form a multi-layered
armored panel 26.
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WO 99/60327 PCT/IL99/00260
Z2
The nature of the solidified material 16 is selected in accordance with the
weight, performance and cost considerations applicable to the intended use of
the
armor.
Armor for land and sea vehicles is suitably made using a metal casting alloy
containing at least 80% aluminium. A suitable alloy is Aluminium Association
No. 535.0, which combines a high tensile strength of 35,000 kg/in2 with
excellent
ductility, having 9% elongation. Further suitable alloys are of the type
containing
5% silicon 8443Ø These alloys are easy to cast in thin sections; their poor
machinability is of little concern in the application of the present
invention. An
epoxy or other plastic or polymeric material, advantageously fiber-reinforced,
is
also suitable.
Tables 1 and 2 are reproductions of test reports relating to epoxy-bound
multi-layer panels as described above with reference to Fig. 1. Each of the
panels
had dimensions of 14" x 14" and had a backing layer 18 made of
DYNEEMA~ 10 mm thick..
The first panel was impacted by a series of three soft-nosed component
7.62 mm projectiles fired at 0° elevation and at a distance of 50 ft.
from the target.
None of the 3 projectiles penetrated the panel.
The second panel was impacted by a series of six soft-nosed component
5.56 mm projectiles, also fired at 0 elevation and at a distance of 50 ft.
from the
target.
None of the 6 projectiles penetrated the panel.
Table 9
H.P. WHITE LABORATORY. INC.
DATA RECORD
-BALLISTIC RESISTANCE TESTS
Date Recd : 04-27-98 Job No. :7592-02
Via: : Hand carried Test Date: 04-27-98
Returned : Hand carried Customer :R & D ETZION
File (HPWLI) : RD-1.PIN
CA 02331529 2000-11-08
WO 99/60327 PCT/IL99/002b0
13
TEST PANEL
Description: PROPRIETARY
Manufacturer: R & D ETZION Sample No. : 12
Size : PT.1 OX12 VT. 14X14 in. Weight : PT. 5.18, VT. 1.97 Ibs.
Thicknesses: na Hardness : na
Avg. Thick. : na Plies/Laminates: NA
AMMUNITION
(1 ): 7.62x51 mm M80 BALL 149.Ogr Lot No.: WfNCHESTER WCC90B001-001
(2): Lot No.:
(3): Lot No.:
(4): Lot No.:
S ET-U P
Vei. Screens : 6.5 ft. & 9.5 ft. Range to Target : 50.0 ft.
Shot Spacing : PER CUSTOMER REQUEST Range Number : 1
Barrel No./Gun: 062 Backing material: 5.5" CLAY/PLYWOOD
Obliquity : 0 deg. Target to Wit. : O.Oin.
Witness Panel : CLAY Conditioning : DRY @71 Deg. F.
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WO 99/60327 PCT/IL99/00260
14
APPLICABLE STANDARDS OR PROCEDURES
(1 ): PER CUSTOMER REQUEST
(2):
(3):
Shot Ammo. Time Velocity Time VelocityAvg.Vel.Pene- Footnotes
No. sxl0-5 ft/s sx10-5 ft/s ft/s tration
1 None DEF.
42X82
mm
2 None DEF.
43X86
mm
3 None DEF.
37x83
mm
FOOTNOTES: REMARKS:
Local
BP-30.06
in.
Hg.
Temp.-71.0
F,
RH-42%
Gunner/Recorder:
BLACK/THOMAS
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WO 99/60327 PCT/IL99/00260
Table 2
H.P. WHITE LABORATORY. INC.
DATA RECORD
-BALLISTIC RESISTANCE TESTS
Date Recd : 04-27-98 Job No. :7592-02
Via: : Hand carried Test Date: 04-28-98
Returned : Hand carried Customer :R & D ETZION
File (HPWLI) : RD-15.PIN
TEST PANEL
Description : PROPRIETARY
Manufacturer: R & D ETZION Sample No. : 8
Size : PT.1 OX12, VT. 14X14 Weight : PT. 7.20, VT. 1.94 Ibs.
in.
Thicknesses: na Hardness : na
Avg. Thick. : na PIies/Laminates: NA
AMMUNITION
(1 ): 5.56x45mm M855 BALL fi2.OgrLot No.:FNB83G001 L002
(2): Lot No.:
Lot No.:
(4):
Lot No.:
SET-UP
Vel. Screens : 6.5 ft. & 9.5 ft. Range to Target : 50.0 ft.
Shot Spacing : PER CUSTOMER REQUEST Range Number : 1
Barrel No./Gun: 038 Backing material: 5.5" CLAY/PLYWOOD
Obliquity : 0 deg. Target to Wit. : O.Oin.
Witness Panel : CLAY Conditioning : DRY @68 Deg. F.
CA 02331529 2000-11-08
WO 99/60327 PCT/IL99/00260
16
APPLICABLE STANDARDS OR PROCEDURES
(1 ): PER CUSTOMER REQUEST
(2):
(3):
Shot Ammo. Time Velocity Time VelocityAvg.Vel.Pene- Footnotes
No. sx10-5 ft/s sx10-5ft/s ft/s tration
1 None DEF.
12x65mm
2 None DEF.
14x61 mm
None DEF.
12x55mm
4 None DEF.
1 Ox54mm
None DEF.
13x62mm
None DEF.
14x61
FOOTNOTES: REMARKS:
Local
BP-30.06
in.
Hg.
Temp.-68.0
F,
RH-48%
Gunner/Recorder:
BLACK/THOMAS
As will be noted, spherical glass pellets, when arranged in a single layer
according to the present invention, enable the preparation of a composite
armor
plate which can withstand multiple impacts in a relatively small area, which
multi-impact protection was not available with prior art amour of comparable
weight.
A plurality of ceramic bodies of substantially cylindrical shape and having
one convexly-curved end face, wherein all of said bodies are of equal size and
shape, each having a height H of 7.5 mm, a diameter D. Of 12.8 mm and a radius
of
curvature R, respectively of 20 mm, 15 mm, 10 mm, 9.5 mm and 9 mm were
prepared from aluminum oxide, SIAION, silicon carbide and boron carbide and
were
placed sequentially in a hydraulic press Model M.50/1 manufactured by Taamal
Mizra, Kibbutz Mizra, Israel, incorporating a C-57-G piston; and capable of
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WO 99/60327 PCT/IL99/00260
17
generating 50 tons of pressure and the shattering points of each body was
recorded as follows:
Table 3
AIz03 SiAiON Silicon Boron
alumina Carbide Carbide
SIC B4C
20 mm R body 5 5.9 5.9 fi.4
15 mm R body 6 7.1 7.1 7.7
mm R body 7.3 8.6 8.6 9.4
9.5 mm R body 7.4 8.7 8.7 9.5
9 mm R body 7.5 8.8 8.8 9.6
Considering that SiAION is lighter in weight than aluminum oxide and has a
surprisingly greater shattering strength, it is ideally suited for use in the
composite
armor plates of the present invention.
It will be evident to those skilled in the art that the invention is not
limited to
the details of the foregoing illustrated embodiments and that the present
invention
may be embodied in other specific forms without departing from the scope of
the
invention as defined by the appended claims.
