U.S. patent application number 11/969937 was filed with the patent office on 2010-11-11 for anti-terror lightweight armor plates and a method of producing same.
Invention is credited to Asher PERETZ.
Application Number | 20100282061 11/969937 |
Document ID | / |
Family ID | 43061566 |
Filed Date | 2010-11-11 |
United States Patent
Application |
20100282061 |
Kind Code |
A1 |
PERETZ; Asher |
November 11, 2010 |
ANTI-TERROR LIGHTWEIGHT ARMOR PLATES AND A METHOD OF PRODUCING
SAME
Abstract
A lightweight armor plate having a contiguous ceramic layer that
absorbs and disperses energy from a projectile. Therefore, the
ceramic layer is generally considered to be the front of armor
plate. The ceramic plate receives the impact of the projectile,
such as but not limited to, bullets and shrapnel. In the case of
bullets, for example, the tip of the bullet is deformed and the
pressure load is reduced by contact with the ceramic plate. Plate
further includes a hardened metal layer situated behind, and
fixedly attached to, contiguous ceramic layer and designed and
constructed to prevent penetration by projectile. The high plastic
elasticity of this hardened metal layer completely absorbs the rest
of the kinetic energy of the bullet through deformation and heat.
Attachment of ceramic layer and hardened metal layer is preferably
by use of an adhesive.
Inventors: |
PERETZ; Asher; (Ramat Efal,
IL) |
Correspondence
Address: |
DR. MARK M. FRIEDMAN;C/O BILL POLKINGHORN - DISCOVERY DISPATCH
9003 FLORIN WAY
UPPER MARLBORO
MD
20772
US
|
Family ID: |
43061566 |
Appl. No.: |
11/969937 |
Filed: |
January 7, 2008 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10861357 |
Jun 7, 2004 |
|
|
|
11969937 |
|
|
|
|
10412312 |
Apr 14, 2003 |
|
|
|
10861357 |
|
|
|
|
10155670 |
May 28, 2002 |
|
|
|
10412312 |
|
|
|
|
60343213 |
Dec 31, 2001 |
|
|
|
Current U.S.
Class: |
89/36.02 ;
148/698; 89/907; 89/910 |
Current CPC
Class: |
C22C 21/06 20130101;
F41H 5/0421 20130101; C22F 1/04 20130101; C22C 21/00 20130101 |
Class at
Publication: |
89/36.02 ;
148/698; 89/907; 89/910 |
International
Class: |
F41H 5/02 20060101
F41H005/02; C22F 1/04 20060101 C22F001/04 |
Claims
1. A lightweight armor plate, the plate comprising: (a) a single
contiguous ceramic layer; and (b) a single hardened metal layer
fixedly attached to said ceramic layer, and said single hardened
metal layer is an alloy that contains at least one material
selected from the group consisting of aluminum, magnesium, silicon,
titanium, copper, manganese, zinc and chromium.
2. The lightweight armor plate of claim 1, wherein said alloy is a
heat-treated alloy.
3. The lightweight armor plate of claim 1, wherein said hardened
metal layer includes at least seventy percent aluminum by weight
and further includes at least one element selected from the group
consisting of magnesium, silicon, titanium, copper, manganese,
chromium, zinc, beryllium, tungsten and molybdenum.
4. The lightweight armor plate of claim 1, wherein said hardened
metal layer is produced by heating said alloy to a temperature in
excess of 540 degrees centigrade, followed by cooling said alloy to
less than sixty degrees centigrade by immersion in a liquid bath
and thereafter precipitation hardening said alloy by heating to a
temperature between 100 and 170 degrees centigrade.
5. The lightweight armor plate of claim 1, wherein said contiguous
ceramic layer includes primarily at least one material selected
from the group consisting of Alumina (Al2O3) and Magnesia
(MgO).
6. A method for producing a hardened metal plate for use in an
armor plate, the method comprising the steps of: (a) heating an
aluminum alloy to a temperature in excess of 540 degrees
centigrade; (b) immersing said aluminum alloy in a liquid bath,
thereby cooling to less than 60 degrees centigrade; and (c)
precipitation hardening by second heating said aluminum alloy to a
temperature between 150 and 170 degrees centigrade.
7. The method of claim 6, wherein said first heating is for a
period of between 2 and 18 hours.
8. The method of claim 6, further including the step of waiting at
least 24 hours after said immersing and thereafter performing said
precipitation hardening.
9. The method of claim 6, wherein said cooling is to a temperature
between 20 and 30 degrees centigrade.
10. The method of claim 6, wherein said second heating is to a
temperature of between 155 and 165 degrees centigrade.
Description
[0001] This application is a Continuation-In-Part of U.S. patent
application Ser. No. 10/861,357 filed 7 Jun. 2004, which is a
Continuation-In-Part of U.S. patent application Ser. No. 10/412,312
filed 14 Apr. 2003 and currently pending which claimed priority
from U.S. patent application Ser. No. 10/155,670 filed on 28 May
2002 and currently pending which claimed priority from U.S. Patent
Application 60/343,213 filed on 31 Dec. 2001 and now abandoned.
FIELD AND BACKGROUND OF THE INVENTION
[0002] The present invention relates to lightweight armor plates
and, more particularly, armor plates having only two layers, a
contiguous ceramic component and a hardened metal layer, and a
method of producing the armor plate.
[0003] The recent increase in political unrest, financially
motivated crime and/or terrorism in many areas of the world has
caused many people to fear that they are potential targets for
attack with firearms or explosive devices.
[0004] Typically, protection from bullets or shrapnel required use
of expensive and heavy armor. True armored vehicles, such as tanks
and other vehicles designed to withstand artillery shells and
rockets are obviously ill suited to urban travel.
[0005] Previously available minor for normal vehicles was typically
so heavy that it required use of very large motors and/or all wheel
drive transmission systems. This meant that retrofitting a typical
passenger vehicle with armor was virtually infeasible.
[0006] Further, the cost of typical armoring for a vehicle is
prohibitive, owing in part to the types of materials employed and
in part to the amount of armor employed.
[0007] These considerations also apply to armoring static targets
such as buildings, windows and bus stops. Similarly, portable
bulletproof protection has typically been limited to "flack
jackets" and helmets which offer no protection for the face and
often leave arms and legs unprotected.
[0008] While use of armor plates which rely upon ceramic components
is know (e.g. US. 6,112,635 and U.S. Pat. No. 5,200,256), these
references teach use of ceramic beads (i.e. interrupted ceramic
layer). Thus, the prior art teaches against use of a contiguous
ceramic layer. Use of interrupted ceramic layers has, as an
inherent disadvantage, a requirement for orderly assembly, or
packing, of the ceramic beads. Assembly, or packing, of the beads
introduces an expensive manual labor step into the manufacturing
process. Further, these references do not teach the superior
qualities of hardened metal layers as detailed hereinbelow.
[0009] Further, U.S. Pat. No. 4,760,611 teaches use of a ceramic
core entirely covered by a metal envelope. This configuration has,
as an inherent disadvantage, a high weight per unit area. Further,
initial impact of a projectile according to this reference is
against metal, not ceramic material. Such an arrangement fails to
take maximum advantage of the force dissipation realized by
shattering ceramic material. The envelope is pre-stressed as it
cools around the ceramic core so as to inhibit the fragmentation
thereof under shock due to the impact of a projectile. This armor
element, therefore, includes three protective layers and requires
casting as the sole method of production. This requires dedicated
molds, costly casting equipment, resulting in a high retail
price.
[0010] U.S. Pat. No. 4,836,084 discloses an armor plate composite
that is composed of four main components, a ceramic impact layer, a
sub-layer laminate, a supporting element and a backing layer. It
should be noted that each of these main components contain several
sub-layers.
[0011] There is therefore a widely recognized need for, and it
would be highly advantageous to have, lightweight armor plates
having only two layers, a contiguous ceramic component and a
hardened metal layer, and a method of producing the armor plate
devoid of the above limitations.
SUMMARY OF THE INVENTION
[0012] The present invention is armor plates having only two
layers, a contiguous ceramic component and a hardened metal layer,
and a method of producing the armor plate.
[0013] According to the teachings of the present invention there is
provided, a lightweight armor plate, the plate comprising: (a) a
single contiguous ceramic layer; and (b) a single hardened metal
layer fixedly attached to the ceramic layer, and the single
hardened metal layer is an alloy that contains at least one
material selected from the group consisting of aluminum, magnesium,
silicon, titanium, copper, manganese and chromium.
[0014] According to a further teaching of the present invention, a
total thickness of the hardened metal layer and the contiguous
ceramic layer is in the range of 12 to 18 mm.
[0015] According to a further teaching of the present invention,
the alloy is a heat-treated alloy.
[0016] According to a further teaching of the present invention,
the hardened metal layer includes at least seventy percent aluminum
by weight and further includes at least one element selected from
the group consisting of magnesium, silicon, titanium, copper,
manganese, chromium, zinc, beryllium, tungsten and molybdenum.
[0017] According to a further teaching of the present invention,
the hardened metal layer is produced by heating the alloy to a
temperature in excess of 540 degrees centigrade, followed by
cooling the alloy to less than sixty degrees centigrade by
immersion in a liquid bath and thereafter precipitation hardening
the alloy by heating to a temperature between 100 and 170 degrees
centigrade.
[0018] According to a further teaching of the present invention,
the contiguous ceramic layer includes primarily at least one
material selected from the group consisting of Alumina (Al2O3) and
Magnesia (MgO).
[0019] According to a further teaching of the present invention,
the contiguous ceramic layer includes primarily at least one
material selected from the group consisting of Alumina
(Al.sub.2O.sub.3) and Magnesia (MgO).
[0020] There is also provided according to the teachings of the
present invention, a method for producing a hardened metal plate
for use in an armor plate, the method comprising the steps of: (a)
heating an aluminum alloy to a temperature in excess of 540 degrees
centigrade; (b) immersing the aluminum alloy in a liquid bath,
thereby cooling to less than 60 degrees centigrade; and (c)
precipitation hardening by second heating the aluminum alloy to a
temperature between 150 and 170 degrees centigrade.
[0021] According to a further teaching of the present invention,
the first heating is for a period of between 2 and 18 hours.
[0022] According to a further teaching of the present invention,
there is also provided the step of waiting at least 24 hours after
the immersing and thereafter performing the precipitation
hardening.
[0023] According to a further teaching of the present invention,
the cooling is to a temperature between 20 and 30 degrees
centigrade.
[0024] According to a further teaching of the present invention,
the second heating is to a temperature of between 155 and 165
degrees centigrade.
BRIEF DESCRIPTION OF THE DRAWINGS
[0025] The invention is herein described, by way of example only,
with reference to the accompanying drawings. With specific
reference now to the drawings 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 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.
[0026] In the drawings:
[0027] FIG. 1 is a cross section of a lightweight opaque armor
plate constructed and operational according to the teachings of the
present invention;
[0028] FIG. 2 is a cross section of the armor plate of FIG. 1
deployed in the pocket of an attachment device constructed and
operational according to the teachings of the present invention;
and
[0029] FIG. 3 is a perspective view of an attachment system
constructed and operational according to the teachings of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] The present invention is armor plates having only two
layers, a contiguous ceramic component and a hardened metal layer,
and a method of producing the armor plate which can be employed to
protect a target from damage caused by projectiles including, but
not limited to, bullets.
[0031] Specifically, the present invention can be used to armor a
vehicle or a portion thereof. Alternately, or additionally, the
present invention may be employed to protect a structure such as a
building or bus stop, or a portion thereof such as a window or a
door. Alternately, the present invention may be employed as a
portable bulletproof shelter for one or more people. Alternately,
the present invention may be employed in construction of improved
bulletproof clothing.
[0032] The principles and operation of lightweight armor plates and
a method of production according to the present invention may be
better understood with reference to the drawings and accompanying
descriptions.
[0033] Before explaining at least one embodiment of the invention
in detail, it is to be understood that the invention is not limited
in its application to the details of construction and the
arrangement of the components set forth in the following
description or illustrated in the drawings. The invention is
capable of other embodiments or of being practiced or carried out
in various ways. Also, it is to be understood that the phraseology
and terminology employed herein is for the purpose of description
and should not be regarded as limiting.
[0034] For purposes of this specification and the accompanying
claims, the term "projectile" includes, but is not limited to, a
bullet fired from a weapon such as, for example, an M-16, an AK-47
(i.e. Kalashnikov), a Galil assault rifle, an Uzi machine gun, a
pistol, a rifle or similar. Projectile further includes a
collection of small projectiles, for example buckshot fired from a
shotgun shell or shrapnel from an explosive device. The following
bullets are specifically included in the definition of projectile:
AK-47 7.62.times.39AP; AK-47 7.62.times.51AP NATO; M16
5.56.times.45 33-109, M-80 Ball 7.62.times.51, Dragonov machinegun
7.62.times.54AP, and 7.62.times.61 AP Level Four NU Standard.
[0035] For purposes of this specification and the accompanying
claims, the term "explosive device" includes, but is not limited
to, a hand grenade, a pipe bomb and an explosive packet worn or
carried by a suicide bomber. Specifically, suicide bombers are
known to include small metal pieces (e.g. screws, nails) within the
explosive packet to produce shrapnel. These small metal pieces are
included within the definition of projectile.
[0036] For purposes of this specification and the accompanying
claims, the term "impenetrable" indicates a capability of
preventing penetration by a projectile fired from a weapon at a
distance of fifty meters, more preferably four to five meters, most
preferably zero to one meter from the armor plate.
[0037] Referring now to the drawings, FIGS. 1 and 2 depict a
lightweight opaque armor plate 40 including a contiguous ceramic
layer 44. Contiguous ceramic layer 44 absorbs and disperses energy
from a projectile 20. Therefore, the ceramic layer 44 is generally
considered to be the front of armor plate 40. The ceramic layer 44
receives the impact of the projectile, such as but not limited to,
bullets and shrapnel. In the case of bullets, for example, the tip
of the bullet is deformed and the pressure load is reduced by
contact with the ceramic layer 44. Armor plate 40 further includes
a hardened metal layer 46 situated behind, and fixedly attached to,
the contiguous ceramic layer 44 and designed and constructed to
prevent penetration by projectile. The high plastic elasticity of
hardened metal layer 46 completely absorbs the rest of the kinetic
energy of the bullet through deformation and heat. Attachment of
ceramic layer 44 and hardened metal layer 46 is preferably by use
of an adhesive 48.
[0038] Preferably, hardened metal layer 46 is constructed of
heat-treated aluminum or a heat-treated alloy as described in more
detail hereinbelow. For example, hardened metal layer 46 may be an
alloy including at least one of the following materials, while not
being limited to, aluminum, magnesium, silicon, zinc, titanium,
copper, manganese and chromium.
[0039] Preferably opaque plate 40 is deployed in a removable
attachment device 38, as illustrated in FIGS. 2 and 3, and/or is
provided with a coating as described in more detail
hereinbelow.
[0040] Preferably, contiguous ceramic layer 44 includes primarily
Alumina (Al.sub.2O.sub.3), Magnesia (MgO) or a combination thereof.
Preferably layer 44 is 96% Alumina, more preferably 98% Alumina,
most preferably between 98% and 100% Alumina.
[0041] Preferably plate 40 is supplied in relatively small pieces
so that a total weight of each piece does not exceed 20 kg, more
preferably 15 kg, still more body shield, a portion of a helmet or
a portable protective wall. Preferably, plate 40 is used in
conjunction with an existing surface such as, for example, a car
door. Most preferably plate 40 is removably attachable to an
existing surface to render it bulletproof.
[0042] The heat-treated alloy may include, for example, magnesium,
copper and silicon and/or combinations thereof. Thus, according
different preferred embodiments of the invention, the hardened
metal layer 46 may contain materials including, but not limited to,
aluminum, magnesium, silicon, titanium, zinc, copper, manganese and
chromium.
[0043] Examples of alloys known to be useful in construction
hardened metal layer 46 are provided in Table 1. These compositions
are provided as examples only and are not intended to limit the
scope of the invention. One ordinarily skilled in the art of
metallurgy will be able to adjust the exact composition of an alloy
to slightly alter weight or elasticity by adding, for example, rare
earth metals such as tungsten, molybdenum or beryllium according to
guidelines set fort in metallurgy texts. Addition of small
quantities of such metals to the alloy is within the scope of the
present invention.
TABLE-US-00001 TABLE 1 Alloys useful in construction of hardened
metal layers MATERIAL WEIGHT PERCENTAGE Magnesium (Mg) 0.3-5.0
Silicon (Si) 0.0-8.0 Titanium (Ti) 0.0-10.0 Copper (Cu) 0.0-5.0
Manganese (Mn) 0.0-1.0 Chromium (Cr) 0.0-5.0 Aluminum (Al)
70.0-90.0 Zinc (Zn) 0.0-10.0
[0044] Thus, according to some preferred embodiments of the
invention hardened metal layer 46 may include 0.45 to 0.6%
magnesium; 6.7 to 7.5% silicon; approximately 0.2% titanium and
aluminum, for example 91.7 to 92.65% aluminum.
[0045] According to alternate preferred embodiments of the
invention hardened metal layer 46 may include 2.1 to 2.9%
magnesium; 1.2 to 2% copper; approximately 0.3% manganese; 0.18 to
0.35% chromium and aluminum, for example 94.45 to 96.22%
aluminum.
[0046] According to additional alternate preferred embodiments of
the invention hardened metal layer 46 may include 1.2% to 1.8%
magnesium; 3.8 to 4.9% copper; approximately 0.3 to 0.9% manganese;
and aluminum, for example 92.4 to 94.7% aluminum.
[0047] According to further additional alternate preferred
embodiments of the invention hardened metal layer 46 may include
0.8 to 1.2% magnesium; 0.15 to 0.4% copper; approximately 0.4 to
0.8% silicon; and aluminum, for example 97.6 to 98.65%
aluminum.
[0048] Methods for preparation of alloys are well known in the art
and detailed description of common methods may be found, for
example, in "Principles of Metal Casting" (Eds. Heine and
Rosenthal, McGraw Hill Book Co.; 1955). and in "Symposium on
Principles of Gating" published by the American Foundrymen's
Society (1951) or in "Casting Aluminum" by C.W. Ammen (Tab Books
Inc.; 1985) or in "Metallurgy of Aluminum Alloys by M. van Lancker
(Chapman and Hall Ltd.; 1967). Each of these texts is fully
included herein by reference.
[0049] The term "heat treatment" or "heat-treated" as used herein
preferably refers to a process which includes precipitation
hardening, tempering, solution treatment or combinations thereof.
As used herein, the term "tempering" specifically includes rapid
cooling, for example by immersion in a chilled water bath or ice
and water slurry.
[0050] Thus, one method for preparation of a hardened metal alloy
according to the teachings of the present invention includes
solution treatment followed by tempering in an ice/water bath
followed by precipitation hardening. This process imparts
previously unachieved properties to the resultant alloy, for
example elongation of 11-16%, as apposed to the 5-9% currently
achieved in the art.
[0051] The solution treatment accomplishes the alloying of the
metals in which the alloying metals either replace some of the
base-metal atoms (substitutional solid solution) or occupy some of
the space between the base-metal atoms (interstitial solid
solution). In both cases, the base metal is distorted and the
movement of dislocations is retarded, thereby hardening the metal.
It should be noted that every fabric metal includes faults. These
faults are generally referred to as "dislocations" The movement of
the dislocations in the metal reduces the overall strength of the
metal. The strength of the metal is increased by retarding the
movement of the dislocations within the base-metal.
[0052] Solution treatment may be accomplished, for example by
heating the alloy to a temperature in excess of 500 degrees
centigrade, more preferably 540 to 550 degrees centigrade, most
preferably approximately 543 degrees centigrade a period of two to
eighteen hours. The alloy is subsequently cooled to less than 60
degrees centigrade, more preferably 20 to 30 degrees centigrade by
immersion in a liquid bath, for example an ice water bath or
chilled acetone/ethanol bath for four to ten seconds. This process
imparts a "potential hardness" to the alloy.
[0053] Precipitation hardening may be accomplished by, for example,
heating the alloy to a moderate temperature, preferably 150 to 170
degrees more preferably 155 to 165 degrees centigrade. Preferably,
precipitation hardening is performed 24 hours or more after
solution treatment.
[0054] This process increases the hardening of the metal by
producing a "traffic" effect of the alloying elements that move
rapidly and retard the dislocations, thereby strengthening the
metal alloy.
[0055] These industrial processes are described in greater detail
in American Standards MIL-A-21180 (casting); MIL-A-6088 (heat
treatment) and MIL-ASTM-B26 (all published by the U.S. Government
Printing office; 1971) which are fully incorporated herein by
reference.
[0056] Preferably plate 40 is deployed in a removable attachment
device 38 as mentioned hereinabove. Thus, attachment device 38 may
be, for example, a sling 50 or a pocket 52, both of which include a
pair of attachment hooks 54 and an attachment rod or band 56.
Alternately, but also preferably, the attachment device may take
the form of suction cups (not shown).
[0057] In order to facilitate ease of handling, plate 40 may
further include a coating (not shown). The coating may be, for
example, rubber, plastic or fabric. Preferably fabric coatings are
bonded to plate 40 with a suitable adhesive.
[0058] An article of clothing modified to accommodate the at least
one lightweight armor plate 40 may be produced, for example, by
incorporating pockets designed to engage and retain one or more
plates 40 into, for example, the legs of a pair of trousers.
Alternately, or additionally, one or more plates 40 may be sown
between layers of fabric when manufacturing a garment.
[0059] Although the invention has been described in conjunction
with specific embodiments thereof, it is evident that many
alternatives, modifications and variations will be apparent to
those skilled in the art. Accordingly, it is intended to embrace
all such alternatives, modifications and variations that fall
within the spirit and broad scope of the appended claims.
* * * * *