( 12 ) united states patent ( 10 ) patent no . : us 10 , 281 , 242 b2 … · 2020. 4. 24. ·...

US010281242B2

( 12 ) United States Patent Knies et al .

( 10 ) Patent No . : US 10 , 281 , 242 B2 ( 45 ) Date of Patent : May 7 , 2019

( 54 ) MATERIAL AND PROCESS FOR COUPLING IMPULSES AND SHOCKWAVES INTO SOLIDS

( 58 ) Field of Classification Search CPC . . . . . . . . . . . . F41H 5 / 013 ; F41H 5 / 04 ; F42D 5 / 045 USPC . . . . . . . . . . . . . . . . . . . 42 / 36 . 01 – 36 . 17 ; 89 / 36 . 01 – 36 . 17 See application file for complete search history .

( 71 ) Applicants : David L . Knies , Marbury , MD ( US ) ; Kenneth S . Grabowski , Alexandria , VA ( US ) ; Alex E . Moser , Fort Washington , MD ( US )

( 56 ) References Cited U . S . PATENT DOCUMENTS

( 72 ) Inventors : David L . Knies , Marbury , MD ( US ) ; Kenneth S . Grabowski , Alexandria , VA ( US ) ; Alex E . Moser , Fort Washington , MD ( US )

( 73 ) Assignee : The United States of America , as represented by the Secretary of the Navy , Washington , DC ( US )

( * ) Notice : Subject to any disclaimer , the term of this patent is extended or adjusted under 35 U . S . C . 154 ( b ) by 337 days .

4 , 179 , 979 A * 12 / 1979 Cook et al . 89 / 36 . 02 4 , 704 , 943 A * 11 / 1987 McDougal 89 / 36 . 02 4 . 757 , 742 A * 7 / 1988 Mazelsky . . . . . . . . . 89 / 36 . 02 7 , 685 , 922 B1 * 3 / 2010 Martin . . . . . . . . . . . . . . . . . . F41H 5 / 0414

89 / 36 . 01 7 , 866 , 248 B2 * 1 / 2011 Moore et al . . . . . . . . . . . . . . . . 89 / 36 . 02 8 , 646 , 373 B1 * 2 / 2014 Kucherov et al . . . . . . . . . . . 89 / 36 . 11

2002 / 0058450 A1 * 5 / 2002 Yeshurun et al . . . . . . . . . . . . . . 442 / 59 2002 / 0092415 A1 * 7 / 2002 Caron . . . . . . . . . . . . 89 / 36 . 02 2006 / 0013977 A1 * 1 / 2006 Duke . . . . . . . . . . F41H 5 / 04

428 / 36 . 9 2006 / 0201318 A1 * 9 / 2006 LaBrash et al . . . . . . . . . . . . . 89 / 36 . 02 2008 / 0105114 A1 * 5 / 2008 Gabrys . . . . . . . . 89 / 36 . 02 2010 / 0212484 A1 * 8 / 2010 Williams et al . 89 / 36 . 02 2011 / 0067561 A1 * 3 / 2011 Joynt . . . . . . 89 / 36 . 02 2014 / 0099472 A1 * 4 / 2014 Greenhill et al . . . . . . . . . . . . 428 / 147

* cited by examiner

. . . . . .

. . . . . . . .

( 21 ) Appl . No . : 13 / 920 , 807

( 22 ) Filed : Jun . 18 , 2013 ( 65 ) Prior Publication Data

US 2013 / 0340604 A1 Dec . 26 , 2013 Primary Examiner — Stephen Johnson Assistant Examiner — Benjamin S Gomberg ( 74 ) Attorney , Agent , or Firm — US Naval Research Laboratory ; Roy Roberts Related U . S . Application Data

( 60 ) Provisional application No . 61 / 662 , 006 , filed on Jun . 20 , 2012

( 51 ) Int . Ci . F411 5 / 04 F41H 5 / 013 F42D 5 / 045

( 52 ) U . S . Ci . CPC

( 2006 . 01 ) ( 2006 . 01 ) ( 2006 . 01 )

( 57 ) ABSTRACT An armor system includes an armor plate , and an appliqué affixed to an exterior of the armor plate , wherein the appliqué has a density increasing in a direction towards the armor plate and configured to minimize reflection of a blast wave from the armor plate . Also disclosed are method of making such an armor system .

F411 5 / 04 ( 2013 . 01 ) ; F411 5 / 013 ( 2013 . 01 ) ; F42D 5 / 045 ( 2013 . 01 ) 11 Claims , 15 Drawing Sheets

atent May 7 , 2019 Sheet 1 of 15 US 10 , 281 , 242 B2

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FIG . 10A

and 3 : 2 * lount

29244x0 . 5 6061 ALPile

FIG , 10B


* 1 * 1 * X , 625 " thick glass glued to 1 " x170 . 125 " trick Alumina ,

14x14x0 . 125 " Alumina glad to the lup and bottom of the glass .

0 , 5 * plant with the Ausnia and glass blacks assembly glued to A plata

* Diameter : 0 . 75 " kick wood die

FIG . 10C

. 1 5 " hacers w ithin 20 * X28 * 20 . 5 " MHA

mm 15x1 * X625 " Duck glass blacks sledlo 1 " X1 " < 0 . 125 " thick Aumina : The 4 come blockshave 1 " x15x0 . 125 " Alumina glued to the top and bottom of the glass .

0 . 1875 * KHAWI

* * Diameter , 0 . 79 " thick wood diso animatonta 12x129x1 " AMA plate

Am 9x12x4 * SMA base plate

FIG . 10D


Hinanananana 30 " x30 * * * RNA weight Hate

u nacers 24 % 2020 . 5 " HA

12x13 * * . 625 " xck glase piste glued to k * * * * * 0 . 125 " thick Alumnia ; The comess of the alsss plate have tºx1 * * 0 . 125 * Alumina giused to the top and bottom of the aluss .

0 . 1675 " RHS y Aumina and glass

www . i * Diameter : 0 . 75 thick wouxidis NA plate

www . 9x12° * " RHA kase plate

FIG . 10E

im I * PVC eubos glued to the 24 " x 24 " x0 . 875 *

2x Threat bersama 6 Dianeter , 0 . 75 " thickwood dige 0 . 1825 % RHA plate

- 9X1XX " RUA base plate

FIG . 10F


n . 1 . Spacers w

ime 12 * * 12 " X 625 thick glass plate glued to l ' * 1 " ( 0 . 125 " brich Alumita ; The corners of the glass pale have l * * 1 * X0 . 125 " Alumina luot the top and bodom of the glass ,

0 . 1875 * RHAW Alussa 200 glass

gluotto0 . 1825 * - 2x Threat

w a Diameter , 0 . 75 tuck wood dise bermastaus 12 " x13 " XI " Maplate

9x12 / 4 " KHIA base alale

FIG . 10G

m 2 24 " x0 . 5 " RHA yyyyyyyy y yy

om 12 " X12 " * . 625 " trick glass statagud to 995 . 0 . 1275 * RHAM 0 . 5 " Wax : pplique

cater for trotoacament .

FIG . 10H

U . S . Patent May 7 , 2019 Sheet 10 of 15 US 10 , 281 , 242 B2

30°x300x4 " RHA weight plate 1 . 5 " Spacers

0 . 1875 " KHAN

0 . 5 " Wax appliqué 0 . 75 % Wood disc

30 . 75 " 30 . 75 " x 17 " thicksteat box

FIG . 101

- 30 " 30 " x4 " AHA Weight plate h 1 5 " Spacers -

- 24 " x24 " x0 . 5 * RMA * * * * * * * * * * * * * * * * * * * * * * * *

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30 . 7 $ " x 30 . 75 " x 12 " thick steal box with a 7 * wide by 6 " deep cavityin the Center for threat placerent .

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center for threat placement ,

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30 " x30 * * * * RA Weight plate * * * * * * * 939393333333333333

W - 24 " x24 " X0 . 5 " AHA

www 12 * 12 * * . 625 % thick glass fate glued to 9c3 . * * * * * * * * 3 mm thick Alumiina ( Flat ) .

0 . 75 " Wood disc , 2 . 25 " Foam

30 . 75 " x 20 . 75 * * 12 " thick steel box 2008r for threat placement

FIG . 10L


30 " 630 " x4 " KHÁWeight plate 1 . 5 Spaces

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30 . 75 " x 30 . 75 " x 12 " thick staat box witha 7 " wide by 6 % deep cavity in the

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for 15 Spacers with - 24 " x24 " x0 . 5 " RHA 3 ani air eau .

anastamm 12 ' x12 " * . 625 " thicketass plate glued to500 . 0 . 1875 " RHA -

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total thickness : 1 . 25 "

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30 . 75 " x 30 . 75 " x 12 " thick steal box

FIG . 10N


20 * 430 * 24 " RMA weight plate 1 . 5 " Spacers

24 " x24 " x0 . 5 " RHA

www . son 12 * x 1 . 2 " X 1625 * thick glass plate glued to s ca . * * * * * x3 mun thick Alumina ( Profile ) .

0 . 5 " Wax applique . com

12x12x6 ' Steal box filled with 445 Double - Sifted Top 50jl .

FIG . 100

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311m air sag - wwwmama 12 x13 * * . 625 * tuk glass plate audio 90 .

0 . 1875 * RHAN 0 . 5 " Wax applique

r " soil coverage 12 ' x12 ' x 6 steel box filled with AAS Double - Si?ted Tog Sos .

FIG . 10P


w 90 * * 20 * * * AMA weight plate 2 . 5 " Spacer ' s

24 " x 24 " X0 . 5 " RUA 4 . 23 . 7 * x 7 " x0 . 5 " Mato

* 32 * 13 * X , 625 % Brick glass plate glued to 9 , 0 . 5 " Wax spalice

12 ' x12 ' * 6 ' Stear box filled with AS ttt !

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FIG . 100

30 " x 30 " x 4 " RHA Weight plate

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0 . 1875 " AND 12 " x 12 " X 635° Ovek elass plate glued to 3 03 . * * * * * x3 mm thick Alunina Flat } .

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- 30 " x 30 " * * * RHÀ weight plata

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FIG . 105

US 10 , 281 , 242 B2

MATERIAL AND PROCESS FOR COUPLING IMPULSES AND SHOCKWAVES INTO

SOLIDS

FIG . 9 shows a schematic representation of a test con figuration . The armor appliqué is bolted on to the bottom of the armor system .

FIGS . 10A - 10S illustrate various test configurations used . CROSS - REFERENCE TO RELATED

APPLICATIONS DETAILED DESCRIPTION

This Application claims the benefit of U . S . Provisional Definitions Application 61 / 662 , 006 filed on Jun . 20 , 2012 , is incorpo Before describing the present invention in detail , it is to rated herein by reference in its entirety . 10 be understood that the terminology used in the specification

is for the purpose of describing particular embodiments , and BACKGROUND is not necessarily intended to be limiting . Although many

methods , structures and materials similar , modified , or In order to reduce harm to persons and property , it is equivalent to those described herein can be used in the

desirable to mitigate high intensity impulses such as from 15 practice of the present invention without undue experimen blasts and projectiles . These impulses can arise from IEDs tation , the preferred methods , structures and materials are ( Improvised Explosive Devices ) , mines , and the like . described herein . In describing and claiming the present

invention , the following terminology will be used in accor BRIEF SUMMARY dance with the definitions set out below .

20 As used in this specification and the appended claims , the In one embodiment , an armor system includes an armor singular forms “ a ” , “ an , ” and “ the ” do not preclude plural

plate , and an appliqué affixed to an exterior of the armor referents , unless the content clearly dictates otherwise . plate , wherein the appliqué has a density increasing in a As used herein , the term “ and / or ” includes any and all direction towards the armor plate and configured to mini - combinations of one or more of the associated listed items . mize reflection of a blast wave from the armor plate . 25 As used herein , the term “ about " when used in conjunc

In another embodiment , a method of forming an armor tion with a stated numerical value or range denotes some system includes affixing an appliqué to an exterior of an what more or somewhat less than the stated value or range , armor plate , wherein the appliqué has a density increasing in to within a range of + 10 % of that stated . a direction towards the armor plate and configured to Description minimize reflection of a blast wave from the armor plate . 30 For blast mitigation , it can be shown from first principle

momentum and energy conservation considerations that the BRIEF DESCRIPTION OF THE DRAWINGS minimum momentum and kinetic energy transfer occurs for

a maximum inelastic collision . To accomplish this requires FIG . 1 illustrates the transition energy involved when a a structure that both maximizes energy dissipation and

brittle material is used to mitigate a shock wave . In the case 35 provides ideal coupling . Described here are appliqués to of glass , it shows the path the reaction takes from bulk glass better match the impedance of the shock wave and blast ( A ) to powdered glass ( B ) . products while allowing for energy dissipation . In one

FIG . 2 illustrates a reaction schematic of a typical solid embodiment , the two functions ( dissipation and coupling ) state organic reaction . Usually , the reaction requires trapping are provided into two separate appliqués , however , it is of excitons near the reaction center and the reacting centers 40 possible to integrate the two functions into a single appliqué . must be in a crystalline lattice no more than 4 Å apart . Materials Considerations for Energy Dissipation However , the large pressure gradients imposed by a blast on One example of impulse mitigation involves a brittle a similar system would likely not require photo - excitation material , such as glass , fracturing , adsorbing energy from ( excitonic ) or a crystalline lattice . the impulse , and preventing the impulse energy from harm

FIG . 3 schematically illustrates various configurations for 45 ing personnel and equipment ( see U . S . Pat . No . 8 , 176 , 831 channel structure . Left - Honey comb structure , Middle and U . S . Patent Publication Nos . 2011 / 0203452 and 2012 / square structure , Right - structure view from a side profile . 0234164 , each of which is incorporated herein by reference ) . The structure is tilted with respect to the channel axis , In order for the brittle glass material within the armor system preventing a direct line - of - sight through the structure . to be an effective energy absorber , it must transition through

FIG . 4 , top , shows a profile or cross - sectional view of 50 a high energy excited state associated with an activation density gradient plate . Density increases ( dark area ) toward barrier between the glass initial state and a final powdered the bottom of the plate . FIG . 4 , bottom , shows a view from state , as noted in Kucherov , et . al . ( reference 1 below ) . The over structured plate . The asperities on the plate need not be difference in energy between the initial and transition state , pyramidal and could be conical , tetrahedral , other geom - AE , dictates the rate , through an Arrhenius - like relationship , etries or a combination of geometries and heights or aspect 55 of the transformation from bulk to powdered glass , seen in ratios FIG . 1 .

FIG . 5 shows side view ( top ) and direct view ( bottom ) of Further , if the energy of the blast is not great enough , the PVC spire - like array . transformation may not proceed and no significant energy

FIG . 6 shows a coupling structure that also minimizes will be absorbed by the glass . Yet , the unabsorbed energy Mach stem formation . 60 may still be greatly detrimental to personnel behind the glass

FIG . 7 shows a combined blast wave focusing ( red ) / armor layer . Polymeric materials and composites have dem density amplifying ( same as FIG . 6 ) and density gradient onstrated an ability to absorb blast energy and a potential for ( gray gradient ) structure . coupling blast waves . Further , the activation barrier energy ,

FIG . 8 schematically illustrates an exemplary impulse AE , is lower than that found in the glass powdering process . mitigation system . In this case , the system is designed to 65 Thus , even at lower blast energies , polymeric materials have protect vehicle and personnel from an impulse from below , the potential to absorb a significant portion of the blast . Also , such that from an IED . since a plastic ' s AE is lower than that of glass , the trans

US 10 , 281 , 242 B2

formation rate will be greater and the total number of finite extreme compressive strain rates experienced during a blast . components in the bulk polymeric material undergoing The impedance matching system as described herein pos transformation will be much greater than that of glass . Thus , sesses a density gradient that minimizes or eliminates a powdering and / or plastic deformation of polymeric materi distinguishable material boundary from which a significant als has been demonstrated to be as , or more effective , than 5 reflected wave can be produced . Such a graded impedance glass . Polymeric materials , since they are typically not as matching system has an advantage over impedance match brittle as glass , are more durable and fieldable , as well . ing layered structures because the graded system can imped Specifically , polyvinylchloride ( PVC ) has been demon ance match a greater range of blast wavelengths than the strated to be a good energy absorbing material , likely due to layered structures . This is because the layered structures are its ability to form extended regions of irreversible plastic 10 optimized to only couple a blast wave of a specific wave deformation upon exposure to a blast . Results of PVC as an energy absorbing layer during blast tests is given in Table 2 length and at a specific angle of incidence . below . This specific type of PVC ( Type I ) may not be the Analogous layered systems have been developed for optimal type for blast protection . There exist several hun optical coatings to either allow or prevent specific wave dred PVC formulations available on the market , so that 15 lengths of light Trom passing througn an optical mate another may prove to be better suited to this application . Another method of coupling optical wavelength into or

However , other plastics may be as good as or better than through an optical material utilizes the concept of an optical PVC due to their inherent structure and solid state reaction or refractive index gradient normal to the surface through topology at extreme pressure gradients , similar to those which the light is intended to pass . Such graded materials found in blasts . For instance , acrylonitrile butadiene styrene 20 and / or surface structures have an advantage over layered ( ABS ) may be a better energy absorber than PVC . The optical structures because they allow a larger range of copolymer contains double bond groups that could react optical wavelengths to pass through the optical system . during a high pressure gradient generated by a blast . Similar material system and process is proposed to maximize types of reactions have been studied previously by Eckhardt , coupling of the shock and blast wave into an armor system ' s et . al . , and others in the field of solid - state organic reactions 25 front panel , utilizing the concepts of a graded material ( see references 1 - 3 below ) . Basically , the reaction scheme in density and structure design . solid - state organic photoreactions follow a path from two Structures of the Material System adjacent double bond moieties to a single cyclobutane ring Impedance matching appliqués can be made from struc as shown in FIG . 2 . tures , for example , channels used commercially as catalytic

Similarly , blast energy can be absorbed by means of a 30 converter support substrates , and can be used wholly or as materials phase transitions including solid - solid , solid - liq - part of a blast mitigation system . The channel structure can uid , solid - vapor , and liquid - vapor . For example , paraffin and be mounted such that the channels are directed toward the paraffin polymer composites can be engineered to have a blast origin or directed at an angle such that the back of the range of melting points tunable to optimize blast energy channel openings are obscured by the channel geometry . The absorption for a specific application . 35 channels can have any pattern including square or hexago

Structures for Shock Wave and Blast Product Impedance nal - exemplary structures are shown in FIG . 3 . Such chan Matching nels can trap the blast wave to minimize its reflection .

As a result of the natural laws of conservation of momen - In another embodiment , the coupling system comprises a tum and energy , the best possible case for energy dissipation binder / filler material and material structure for enabling a and minimum momentum transfer occurs for a maximum 40 density gradient to be created parallel to the impulse propa inelastic collision of the shock and blast wave . This occurs gation direction . The binder may be comprised of paraffin when there is no reflection of the shock and blast waves , that with or without a specific n - alkane distribution , a pure metal is , the effective impedance of the armor matches that of the or metal alloy , a polymer or copolymer , or polymer blend , or incoming shock and blast wave . The impedance matching a variety of different configurations comprised of the afore layer as described herein improves shock and blast wave 45 mentioned materials . coupling into the armor front plate , thereby reducing the The material for enabling a density gradient may be intensity of the reflected waves and minimizing kinetic comprised of hollow and / or non - hollow nano - and / or micro energy and momentum transfer to the armor system . The spheres , in which the hollow is fully or partially evacuated , energy carried by the shock and blast waves can be trans - or filled with a solid , liquid , or gas or mixture thereof . Since formed and stored in a sacrificial layer that can react in the 50 bimodal particle distributions can produce a greater density , time it takes for the shock wave to travel across individual they can create a larger density gradient within a structure . atomic planes , - 0 . 1 psec . As previously demonstrated , fail - The spheres may be monotonic , bi - distributed , or may have ure wave energy absorption by a brittle material placed a specific particle size distribution . The spheres can be a behind the armor front plate can facilitate the stringent mixture of two or more sphere types having different com requirement . 55 positions as described above . Two different sphere types

Previous armor systems have utilized layered structures of could have different densities and sizes and enable a density alternating density materials to maximize coupling of the gradient to be formed . shock and blast wave to components comprising the armor In one embodiment , the coupling structure may be made system , designed to adsorb energy from the impulse . How - from spheres with at least a bi - modal distribution packed ever , the previous armor systems ' front surfaces have been 60 and or vibrated to enable the smaller spheres to settle closer comprised of a hard material which maximizes blast and to the bottom of the structure and interstitial to the larger shock wave reflection . Even an armor system having a softer microspheres . front surface may produce a significant reflected blast wave In a further embodiment , shown in FIG . 4 , a spire - like due to the softer material ' s behavior under the extreme array structure served to couple a blast wave from air into a compressive strain rates experienced during a blast . Mate - 65 solid material . The coupling material was comprised of rials that typically display significant compliance under ceramic microparticles and glass microspheres in a wax moderate strain rates will display low compliance under the binder in which the particles and microspheres produced a

US 10 , 281 , 242 B2 6

density gradient to reduce blast wave reflection and increase or adhesive system . To accommodate a diverse set of blast wave transmission into the solid material backing the required applications , the coupling system can be made from wax gradient appliqué . smaller components and tiled together on the armor system ' s

Blast tests were also completed using a material without front surface . a density gradient but with a spire - like structure , demon - 5 The aforementioned technique has undergone initial proof strating the ability of these structures to couple a blast wave of concept at a certified blast test range and has shown into a material . The structure was comprised of a 12 " x12 " x promising results , despite use of a gradient material having 0 . 8 " type 1 polyvinylchloride sheet having sharp pyramid unoptimized properties . structures ( see FIG . 5 ) . The pyramid face - apex - opposite Jump height provides relevant and reliable data associated pyramid face ( PAP ) angle was 30° . To obtain focusing of the 10 with blast testing ( see FIG . 9 ) of the device under test blast wave as it interacts with the structure the spire face ( DUT ) . The jump height is used to calculate momentum and to - face angle must be less than a specific critical angle that energy transfer to the DUT by assuming the DUT starts at prevents reflection of the blast wave and is dependent of the rest , and is again at rest at the maximum jump height . At this

point , all the kinetic energy imparted to the DUT by the symmetry and structure of the spire - like array . 15 threat is converted to potential energy . Ideally , the spire - like structure is made having a spire - like Table 1 shows a summary of some test results . Concept 3 geometry resembling a set of tangent function ( see FIG . 6 ) . This structure will minimize Mach - stem behavior at the is a construction similar to that shown in FIG . 8 . The blast interface and enable better coupling of the blast wave . A Impulse and energy reduction are large ; 31 . 1 % and 54 . 3 % , combined system is also shown in FIG . 7 , which optimizes , respectively . Concepts 1 and 2 are variants of the most

20 successful concept 3 system . coupling into the backing material . Preparing a Density Gradient Structure In an embodiment , the density gradient structure is made TABLE 1

by combining the appropriate materials comprising the Blast test results of blast mitigation system described herein structure into a homogenous composition , casting the homo - 36 geneous composition into a mold and causing the density Total Weight TNT Jump Height Impulse Energy gradient to be developed by an appropriate method . ( lbs . ) Configuation ( lbs . ) ( inches ) Reduction Reduction

For material cast into a mold , the system can be main 1050 Reference / 1 . 63 30 . 1 tained at a temperature and time adequate for diffusion of Control particles in the system to create a density gradient . If the 20 1089 Concept 1 1 . 61 27 . 0 2 . 5 % 8 . 4 %

1050 Concept 2 1 . 62 19 . 4 20 . 3 % 36 . 5 % temperature and temperature fluctuations in the system are 1090 Concept 3 1 . 63 13 . 4 31 . 1 % 54 . 3 % adequate the particles have enough energy to rearrange such 1050 Reference / 1 . 60 31 . 0 that the denser and / or smaller particles settle to the bottom Control while the larger and / or less dense particles migrate to the top of the casting volume . 35 This diffusion process can be augmented by additionally TABLE 2 vibrating the mold or casting to impart energy into the particles to enhance the particle diffusion process within the Jump height from blast tests

cast fluid . Typically , ultrasonic and sonic frequencies should be adequate to achieve faster migration of the particles 40 Jump Height Decrease in Jump

( inches ) * Height ( % ) within the casting . To obtain a graded structure , the mold can have a struc Control 186 . 15

tured surface mirroring that of the desired structure of the PVC energy absorber / 147 . 22 25 . 4

density graded material . Alternatively , blocks of the density erial Alternatively blocks of the density impedance matching appliqué graded material can be ground or machined to have the 15 appropriate structure . Blast testing of an embodiment having a cordierite chan

Application of the Density Gradient Structure nel structure demonstrated a plate jump height reduction of The density gradient material made from the aforemen - 30 . 5 % compared to control , from 186 . 15 inches in the

tioned materials and process is applied to the front surface control to 129 . 31 inches . of armor intended to mitigate the impulse from a blast or so Blast testing of the PVC structured coupler of FIG . 5 projectile . The application can be made through mechanical resulted in a 27 % decrease in jump height compared to a bonding by direct casting onto the roughened front surface control , from 216 . 2 inches to 170 inches . or aflixing the system to the front surface using a thin epoxy Further test results are show below in Table 3 .

TABLE 3

Results of additional blasts test shots . “ On Ground ” means the charge was placed on a thick metal plate . “ Pot ” means the charge

is placed in a steel pot , with the top of the charge level with ground . “ In Ground ” means the charge top is 1 inch below ground in water - saturated soil .

Charge Energy Impulse Reduction ( % ) Reduction ( % ) Shot Configuration Location Size

5 Solution 0 6 Solution 0

10 Solution 1 ( Squares ) 11 Solution 1 ( Squares ) 13 Solution 1 ( Squares )

On Ground On Ground On Ground On Ground On Ground

1 X TNT 2 X TNT 2 X TNT 2 X TNT 2 X TNT oneet

US 10 , 281 , 242 B2

TABLE 3 - continued

Results of additional blasts test shots . “ On Ground ” means the charge was placed on a thick metal plate . “ Pot ” means the charge

is placed in a steel pot , with the top of the charge level with ground . “ In Ground ” means the charge top is 1 inch below ground in water - saturated soil .

Charge Size

Energy Impulse Reduction ( % ) Reduction ( % ) Shot Configuration Location

15 Solution 1 ( no Wax ) On Ground 16 Solution ( PVC cubes ) On Ground 17 Solution 1 On Ground 20 Solution 1 Pot 21 Solution 1 Pot 24 Solution 1 Pot 25 Solution 1 Pot 27 Sol . 1 - C only Pot 28 Sol . 1 - EA ( PVC ) Pot 29 Solution 1 Pot 30 Sol . 1 - EA only Pot 32 Sol . 2 - C ( Cordierite ) Pot 34 Solution 1 In Ground 36 Solution 1 In Ground 38 Solution 1 In Ground 40 Solution 1 In Ground 42 Sol . 1 - no Al In Ground 44 Sol . 1 - C ( PVC ) In Ground 45 Sol . 1 - EA ( PVC ) In Ground

2 X TNT 2 X TNT 2 X TNT 1 X C4 1 X C4 2 X C4 2 X C4 2 X C4

X C4 2 X C4 2 X C4 2 X C4 2 X TNT 2 X TNT 1 X TNT

| 1 X TNT 2 X C4 2 X C4 2 X TNT

006Ewaung Fu o w

The configuration details for these additional tests were as Shot 15 ( corresponding to FIG . 10E ) : follows . Target Configuration ( from top to bottom ) :

Shot 5 ( corresponding to FIG . 10A ) target configuration 30 " x30 " x4 " thick RHA Weight ( from top to bottom ) : 30 1 . 5 " Al Spacers 30 " x30 " x4 " thick rolled homogeneous armor ( RHA ) weight 24 " x24 " x0 . 5 " RHA 2 . 125 " Al Spacers ( w / added washers to increase air gap to fit 4 ea . 1 " X1 " x0 . 125 " Alumina

pressure mount ) 12 ' x12 ' x5 / 8 " glass plate 24 " x24 " x0 . 5 " thick RHA plate ( w / 2 . 25 " hole in center of 17 ea . 1 " x15x0 . 125 " Alumina

plate for pressure gauge ) 35 24 " x24 " x0 . 1875 " RHA 24 " x24 " x0 . 5 " thick Profile Al plate ( w / 2 . 25 " hole in center 24 " x24 " x0 . 5 " Al

of plate for pressure gauge ) Total Target Weight : 1 , 089 lbs . Total Target Weight : 1 , 050 lb . Shot 16 ( corresponding to FIG . 10F ) :

Shot 6 ( corresponding to FIG . 10B ) target Configuration Target Configuration ( from top to bottom ) : ( from top to bottom ) : 40 30 " x30 " x4 " thick RHA Weight 30 " X30 " x4 " thick RHA Weight 1 . 5 " Al Spacers 2 . 125 " Al Spacers ( w / added washers to increase air gap to fit 24 " x24 " x0 . 5 " RHA

pressure mount ) 53 ea — 1 " cube PVC 24 " x24 " x0 . 5 " thick RHA plate 24 " x24 " x0 . 1875 " RHA 24 " x24 " x0 . 5 " thick Profile Al plate 45 24 " x24 " x0 . 5 " Al Total Target Weight : 1 , 050 lbs Total Target Weight : 1 , 050 lbs .

Shots 10 and 11 ( corresponding to FIG . 10C ) : Shot 17 ( corresponding to FIG . 10G ) : Target Configuration ( from top to bottom ) : Target Configuration ( from top to bottom ) : 30 " x30 " x4 " thick RHA Weight 30 " x30 " x4 " thick RHA Weight 1 . 5 " Al Spacers 50 1 . 5 " Al Spacers 24 " x24 " x0 . 5 " thick RHA 24 " x24 " x0 . 5 " RHA 4 ea . 1 " X1 " x0 . 125 " thick Alumina 4 ea . 1 " x15x0 . 125 " Alumina 64 ea . 1 " x1 " x0 . 625 " thick glass blocks 12 ' x12 ' x5 / 8 " glass plate 64 ea . 1 " x1 " x0 . 125 " thick Alumina 17 ea . 1 " X1 " x0 . 125 " Alumina 24 " x24 " x0 . 5 " Al ( Flat ) 55 24 " x24 " x0 . 1875 " RHA Total Target Weight : 1 , 055 lbs . 24 " x24 " x0 . 5 " Al

Shot 13 ( corresponding to FIG . 10D ) : 12 ea . 2 " x2 " x0 . 5 " Wax w / particles ( facing blast ) Target Configuration ( from top to bottom ) : Total Target Weight : 1 , 090 lbs . 30 " x30 " x4 " thick RHA Weight Shots 20 and 21 ( corresponding to FIG . 10H ) : 1 . 5 " Al Spacers 60 Target Configuration ( from top to bottom ) : 24 " x24 " x0 . 5 " RHA 30 " X30 " x4 " thick RHA Weight 4 ea . 1 " X1 " x0 . 125 " thick Alumina 1 . 5 " Al Spacers 9 ea . 1 " X1 " x0 . 625 " thick glass blocks 24 " x24 " x0 . 5 " RHA 9 ea . 1 " x1 " x0 . 125 " thick Alumina 3 mm air gap 24 " x24 " x0 . 1875 " RHA 65 12 " X12 " x0 . 625 " Glass 24 " x24 " x0 . 5 " Al 3 mm Alumina Amplifier - Profile ( 9 ea . 4 " x4 " tiles — 3x3 Total Target Weight : 1 , 085 lbs . grid )

5

US 10 , 281 , 242 B2 10

24 " x24 " x0 . 1875 " RHA 3 mm Alumina Amplifier - Flat ( 9 ea . 4 " x4 " tiles — 3x3 grid ) 0 . 5 " A1 24 " x24 " x0 . 1875 " RHA 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 0 . 5 " Al Total Target Weight : 1 , 086 lbs . 48 ea . 3 " x2 . 5 " x9 mm thick Cordierite ( 4x4 grid _ triple Shots 24 and 25 ( corresponding to FIG . 101 ) : stacked ) Target Configuration ( from top to bottom ) : Total Target Weight : 1 , 087 . 1 lbs . 30 " x30 " x4 " thick RHA Weight Shots 34 and 36 ( corresponding to FIG . 100 ) : 1 . 5 " Al Spacers Target Configuration ( from top to bottom ) : 24 " x24 " x0 . 5 " RHA 30 " x30 " x4 " thick RHA Weight 3 mm air gap 10 1 . 5 " Al Spacers 12 ' x12 ' x0 . 625 " Glass 24 " x24 " x0 . 5 " RHA 3 mm Alumina Amplifier - Profile ( 9 ea . 4 " x4 " tiles — 3x3 3 mm air gap grid ) 24 " x24 " x0 . 1875 " RHA 12 ' x12 ' x0 . 625 " Glass 0 . 5 " Al 15 . 3 mm Alumina Amplifier - Profile ( 9 ea . 4 " x4 " tiles — 3x3 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) grid ) Total Target Weight : 1 , 086 lbs . 24 " x24 " x0 . 1875 " RHA

Shot 27 ( corresponding to FIG . 10J ) : 0 . 5 " A1 Target Configuration ( from top to bottom ) : 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 30 " X30 " x4 " thick RHA Weight 20 Total Target Weight : 1 , 086 lbs . 1 . 5 " Al Spacers Shots 38 and 40 ( corresponding to FIG . 10P ) : 24 " x24 " x0 . 5 " RHA Target Configuration ( from top to bottom ) : 0 . 5 " A1 30 " X30 " x4 " thick RHA Weight 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 1 . 5 " Al Spacers Total Target Weight : 1 , 042 . 4 lbs . 25 24 " x24 " x0 . 5 " RHA

Shot 28 ( corresponding to FIG . 10K ) : 3 mm air gap Target Configuration ( from top to bottom ) : 12 " x12 " x0 . 625 " Glass 30 " x30 " x4 " thick RHA Weight 3 mm Alumina Amplifier - Profile ( 9 ea . 4 " x4 " tiles3x3 1 . 5 " Al Spacers grid ) 24 " x24 " x0 . 5 " RHA 30 24 " x24 " x0 . 1875 " RHA 3 mm air gap 0 . 5 " A1 100 ea . 1 " PVC cubes ( 10x10 grid — 12 " x12 " ) 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 24 " x24 " x0 . 1875 " RHA Total Target Weight : 1 , 083 . 9 lbs . 0 . 5 " Al Shot 42 ( corresponding to FIG . 10Q ) : 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 35 Target Configuration ( from top to bottom ) : Total Target Weight : 1 , 078 . 6 lbs . 30 " X30 " x4 " thick RHA Weight

Shot 29 ( corresponding to FIG . 10L ) : 1 . 5 " Al Spacers Target Configuration ( from top to bottom ) : 24 " x24 " x0 . 5 " RHA 30 " x30 " x4 " thick RHA Weight 4 ea . 2 " x2 " x0 . 5 " Iso - Damp ( positioned in the 4 corners on 1 . 5 " Al Spacers 40 top of the glass ) 24 " x24 " x0 . 5 " RHA 12 ' x12 ' x0 . 625 " Glass 3 mm air gap 3 mm Alumina Amplifier - Flat ( 9 ea . 4 " x4 " tiles3x3 grid ) 12 " X12 " X0 . 625 " Glass 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 3 mm Alumina Amplifier - Flat ( 9 ea . 4 " x4 " tiles — 3x3 grid ) Total Target Weight : 1 , 086 lbs . 24 " x24 " x0 . 1875 " RHA 45 Shot 44 ( corresponding to FIG . 10R ) : 0 . 5 " A1 Target Configuration ( from top to bottom ) : 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 30 " x30 " x4 " thick RHA Weight Total Target Weight : 1 , 086 lbs . 1 . 5 " Al Spacers

Shot 30 ( corresponding to FIG . 10M ) : 24 " x24 " x0 . 5 " RHA Target Configuration ( from top to bottom ) : 50 3 mm air gap 30 " X30 " x4 " thick RHA Weight 12 " x12 " x0 . 625 " Glass 1 . 5 " Al Spacers 3 mm Alumina Amplifier - Flat ( 9 ea . 4 " x4 " tiles - 3x3 grid ) 24 " x24 " x0 . 5 " RHA 24 " x24 " x0 . 1875 " RHA 3 mm air gap 0 . 5 " Al 12 " X12 " x0 . 625 " Glass 55 12 ' x12 x1 " PVC ( Profile ) 3 mm Alumina Amplifier - Profile ( 9 ea . 4 " x4 " tiles — 3x3 Total Target Weight : 1 , 085 . 7 lbs .

grid ) Shot 45 ( corresponding to FIG . 10S ) : 24 " x24 " x0 . 1875 " RHA Target Configuration ( from top to bottom ) : 0 . 5 " Al 30 " x30 " x4 " thick RHA Weight Total Target Weight : 1 , 083 . 1 lbs . 60 1 . 5 " Al Spacers

Shot 32 ( corresponding to FIG . 10N ) : 24 " x24 " x0 . 5 " RHA Target Configuration ( from top to bottom ) : 3 mm air gap 30 " x30 " x4 " thick RHA Weight 12 ' x12 " X1 " PVC ( Flat ) 1 . 5 " Al Spacers 24 " x24 " x0 . 1875 " RHA 24 " x24 " x0 . 5 " RHA 65 0 . 5 " Al 3 mm air gap 0 . 5 " Wax appliqué ( 36 ea . 2 " x2 " tiles — 6x6 grid ) 12 " x12 " x0 . 625 " Glass Total Target Weight : 1 , 084 . 8 lbs .

ju US 10 , 281 , 242 B2

12 All documents mentioned herein are hereby incorporated an appliqué affixed to an exterior of the armor plate ,

by reference for the purpose of disclosing and describing the wherein the appliqué has a density increasing in a particular materials and methodologies for which the docu direction towards the armor plate and is configured to ment was cited . minimize reflection of a blast wave from the armor

Although the present invention has been described in 5 plate , connection with preferred embodiments thereof , it will be the appliqué comprising sharply - pointed spires extending appreciated by those skilled in the art that additions , dele away from the armor plate interspersed with sharply tions , modifications , and substitutions not specifically pointed troughs extending towards the armor plate , the described may be made without departing from the spirit and spires and troughs having a geometry approximating a scope of the invention . Terminology used herein should not 10 tangent function with a magnitude of 1 .

2 . The armor system of claim 1 , wherein the armor system be construed as being " means - plus - function ” language further comprises a layer of polymeric energy absorbing unless the term “ means ” is expressly used in association material . therewith . 3 . The armor system of claim 2 , wherein said polymeric

energy absorbing material is selected from the group con REFERENCES 15 sisting of polyvinylchloride and acrylonitrile butadiene sty rene . Each of the following is incorporated by reference herein 4 . The armor system of claim 1 , wherein the appliqué in its entirety comprises filler particles in a binder configured to contribute ( 1 ) Acoustic waves excited by phonon decay govern the to said increasing density .

fracture of brittle materials , Yan Kucherov , Graham am 20 20 5 . The armor system of claim 4 , wherein said filler Hubler , John Michopoulos , and Brant Johnson J . Appl . particles comprise hollow nano - and / or micro - spheres , in Phys . 111 , 023514 ( 2012 ) . which the hollow is fully or partially evacuated . ( 2 ) Energetics of organic solid - state reactions : the topo 6 . The armor system of claim 4 , wherein said filler chemical principle and the mechanism of the oligomer particles have at least a bimodal size distribution . ization of the 2 , 5 - distyrylpyrazine molecular crystal , N . 257 . The arm M . Peachey and C . J . Eckhardt , Journal of the American pointed spires are exposed to air . Chemical Society 1993 115 ( 9 ) , 3519 - 3526 . 8 . The armor system of claim 1 , further comprising a

( 3 ) General Theoretical Concepts for Solid State Reactions : polymeric material disposed between said spires . Quantitative Formulation of the Reaction Cavity , Steric 9 . The armor system of claim 8 , wherein said polymeric Compression , and Reaction - Induced Stress Using an 30 material has a density gradient . Elastic Multipole Representation of Chemical Pressure , 10 . The armor system of claim 1 , wherein the appliqué is Tadeusz Luty and Craig J . Eckhardt , Journal of the ne affixed to the armor plate via direct casting , epoxy , adhesive , American Chemical Society 1995 117 ( 9 ) , 2441 - 2452 . bolts , or a combination thereof . What is claimed is : 11 . The armor system of claim 1 , wherein the density of 1 . An armor system comprising : 35 each spire increases from spire tip to spire base . an armor plate , and

( 12 ) united states patent ( 10 ) patent no . : us 10 , 281 , 242 b2 … · 2020. 4. 24. ·...

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