Composite armor plate and method for using the same

Abstract

The invention provides an armor plate for absorbing and dissipating kinetic energy from armor piercing 7.62 mm projectiles having a projectile length of from 32.8 mm to 37 mm, the armor plate comprising a plurality of ceramic pellets and a solidified material, each ceramic pellet having a body portion and a convexly curved end portion, each body portion having two opposite ends, an axis passing through each end and a substantially constant cross-section along the axis, and each convexly curved end portion extending from an end of the corresponding body portion, each body portion having a body portion length along the axis between the two ends, the ceramic pellets being embedded in the solidified material so that the solidified material retains the ceramic pellets in a ceramic pellet layer which is one pellet thick with the convexly curved end portions lying at or adjacent an impact receiving side of the armor plate, wherein the ceramic pellet layer is the only layer of ceramic pellets in the armor plate, wherein the ceramic pellet layer has an edge extending therearound formed by a subset of the ceramic pellets, wherein the ceramic pellets are arranged so that the body portion of substantially each pellet, other than of the pellets of the subset, lies in contact with or closely adjacent to the respective body portions of six neighboring ones of the ceramic pellets so that there are a plurality of valleys extending through the ceramic pellet layer with each valley being bordered by three adjacent ceramic pellets, wherein substantially each valley has a shape and size such that the diameter of the largest imaginary circle that will fit into the each valley between the neighboring body portions and substantially perpendicularly to the neighboring axes is from 1.96 mm to 3.7 mm, and wherein each body portion length is from 5.57 mm to 10.73 mm.

1 . An armor plate for absorbing and dissipating kinetic energy from armor piercing 7.62 mm projectiles having a projectile length of from 32.8 mm to 37 mm, the armor plate comprising a plurality of ceramic pellets and a solidified material, each ceramic pellet having a body portion and a convexly curved end portion, each body portion having two opposite ends, an axis passing through each end and a substantially constant cross-section along said axis, and each convexly curved end portion extending from an end of the corresponding body portion, each body portion having a body portion length along said axis between the two ends, the ceramic pellets being embedded in the solidified material so that the solidified material retains the ceramic pellets in a ceramic pellet layer which is one pellet thick with said convexly curved end portions lying at or adjacent an impact receiving side of the armor plate, wherein the ceramic pellet layer is the only layer of ceramic pellets in the armor plate, wherein the ceramic pellet layer has an edge extending therearound formed by a subset of said ceramic pellets, wherein said ceramic pellets are arranged so that the body portion of substantially each pellet, other than of the pellets of said subset, lies in contact with or closely adjacent to the respective body portions of six neighboring ones of the ceramic pellets so that there are a plurality of valleys extending through the ceramic pellet layer with each valley being bordered by three adjacent ceramic pellets, wherein substantially each valley has a shape and size such that the diameter of the largest imaginary circle that will fit into said each valley between the neighboring body portions and substantially perpendicularly to the neighboring axes is from 1.96 mm to 3.7 mm, and wherein each body portion length is from 5.57 mm to 10.73 mm. 
   
   
       2 . An armor plate according to  claim 1 , wherein the diameter of the largest imaginary circle is from 1.96 mm to 3.40 mm and each body portion length is from 5.57 mm to 9.86 mm; or wherein the diameter of the largest imaginary circle is from 2.04 mm to 3.50 mm and each body portion length is from 5.78 mm to 10.15 mm; or
 wherein the diameter of the largest imaginary circle is from 2.10 mm to 3.60 mm and each body portion length is from 5.95 mm to 10.44 mm; or wherein the diameter of the largest imaginary circle is from 2.16 mm to 3.70 mm and each body portion length is from 6.12 mm to 10.73 mm.   
   
   
       3 . A method of manufacturing an armor plate for absorbing and dissipating kinetic energy from armor piercing 7.62 mm projectiles having a predetermined projectile length, comprising:
 selecting said projectile length of said armor piercing 7.62 mm projectiles for which the kinetic energy is to be absorbed and dissipated by said armor plate;   manufacturing the armor plate wherein the armor plate comprises a plurality of ceramic pellets and a solidified material, each ceramic pellet having a body portion and a convexly curved end portion, each body portion having two opposite ends, an axis passing through each end and a substantially constant cross-section along said axis, and each convexly curved end portion extending from an end of the corresponding body portion, each body portion having a body portion length along said axis between the two ends, the ceramic pellets being embedded in the solidified material so that the solidified material retains the ceramic pellets in a ceramic pellet layer which is one pellet thick with said convexly curved end portions lying at or adjacent an impact receiving side of the armor plate, wherein the ceramic pellet layer is the only layer of ceramic pellets in the armor plate, wherein said ceramic pellet layer has an edge extending therearound formed by a subset of said ceramic pellets, wherein said ceramic pellets are arranged so that the body portion of substantially each pellet, other than of the pellets of said subset, lies in contact with or closely adjacent to the respective body portions of six neighboring ones of the ceramic pellets so that there are a plurality of valleys extending through the ceramic pellet layer with each valley being bordered by three adjacent ceramic pellets;   wherein said manufacture includes selecting the size and shape of the ceramic pellets according to the predetermined projectile length so that substantially each valley has a shape and size such that the diameter of the largest imaginary circle that will fit into said each valley between the neighboring body portions and substantially perpendicularly to the neighboring axes is from 6% to 10% of the predetermined projectile length, and wherein each body portion length is from 17% to 29% of the predetermined projectile length.   
   
   
       4 . A method of using an armor plate, said method comprising:
 providing an armor plate comprising a plurality of ceramic pellets and a solidified material, each ceramic pellet having a body portion and a convexly curved end portion, each body portion having two opposite ends, an axis passing through each end and a substantially constant cross-section along said axis, and each convexly curved end portion extending from an end of the corresponding body portion, each body portion having a body portion length along said axis between the two ends, the ceramic pellets being embedded in the solidified material so that the solidified material retains the ceramic pellets in a ceramic pellet layer which is one pellet thick with said convexly curved end portions lying at or adjacent an impact receiving side of the armor plate, wherein the ceramic pellet layer is the only layer of ceramic pellets in the armor plate, wherein said ceramic pellet layer has an edge extending therearound formed by a subset of said ceramic pellets, wherein said ceramic pellets are arranged so that the body portion of substantially each pellet, other than of the pellets of said subset, lies in contact with or closely adjacent to the respective body portions of six neighboring ones of the ceramic pellets so that there are a plurality of valleys extending through the ceramic pellet layer with each valley being bordered by three adjacent ceramic pellets;   Using said composite armor plate for absorbing and dissipating kinetic energy from armor piercing 7.62 mm projectiles having a predetermined projectile length; and   Wherein substantially each valley has a shape and size such that the diameter of the largest imaginary circle that will fit into said each valley between the neighboring body portions and substantially perpendicularly to the neighboring axes is from 6% to 10% of the predetermined projectile length, and wherein each body portion length is from 17% to 29% of the predetermined projectile length.   
   
   
       5 . A method according to  claim 3 , wherein the armor piercing projectile has a tungsten carbide core and the diameter of the largest imaginary circle is from 7% to 9% of the predetermined projectile length. 
   
   
       6 . A method according to  claim 4 , wherein the armor piercing projectile has a tungsten carbide core and the diameter of the largest imaginary circle is from 7% to 9% of the predetermined projectile length. 
   
   
       7 . A method according to  claim 3 , wherein the armor piercing projectile has a tungsten carbide core and each body portion length is from 22% to 29% of the predetermined projectile length. 
   
   
       8 . A method according to  claim 3 , wherein each body portion length is from 19% to 24% of the predetermined projectile length. 
   
   
       9 . An armor plate or method according to  claim 1 , wherein the ceramic pellets are substantially internal within the solidified material and the outer faces of the armor plate are substantially formed by the solidified material. 
   
   
       10 . An armor plate or method according to  claim 1 , wherein the body portion of each ceramic pellets has a maximum cross-sectional dimension of greater than 13 mm, and preferably between 14 mm and 20 mm. 
   
   
       11 . An armor plate or method according to  claim 1 , wherein each ceramic pellet has an overall length along said axis of between 11.6 mm and 17 mm. 
   
   
       12 . An armor plate or method according to  claim 1 , wherein the diameter of said largest imaginary circle is no greater than 3 mm. 
   
   
       13 . An armor plate or method according to  claim 1 , wherein the shape of the body portion of each ceramic pellet is either circular cylindrical, or generally hexagonal with rounded edges between each pair of adjacent axially extending faces. 
   
   
       14 . A multi-layered armor panel comprising an armor plate according to  claim 1 , said armor plate forming an outer layer for deforming and shattering into fragments an impacting high-velocity armor piercing projectile, and a second layer positioned inwardly of and adjacent to the armor plate, the second layer comprising a material that is softer than the ceramic pellets and the second layer capturing the fragments and absorbing the remaining kinetic material from the fragments. 
   
   
       15 . A multi-layered armor panel according to  claim 14 , wherein the second layer is made of: polyethylene with an ultra high molecular weight; aramid; aluminium; steel; titanium; or reinforced fiberglass. 
   
   
       16 . A multi-layered armor panel according to  claim 14 , further comprising a third layer positioned inwardly of the second layer and made of aluminium.