Ballistic Impact Properties

8/2/2019 Ballistic Impact Properties

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Johan Westin

B allistic Im p act P ro p erties o fF ib re -R ein fo rc ed C o m p os iteStructuresA master thesis work in cooperation with FO! and KTH


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TitelTitle

Kompositstrukturers ball istiska egenskaperBallistic Impact Properties of Fibre-ReinforcedComposite Structures

Rapportnr/Report noRapporttypReport TypeSidor/PagesManad/MonthUtgivningsarlY earISSN

Teknisk rapportTechnical report44 PManad/Month2011ISSN 1650-1942

Kund/CustomerProjek!nr/Project noGodksnd av/Approved by

ForsvarsmaktenE20511Patrik Lundberg

FOI, Totalforsvarets ForskningsinstitutAvdelningen fOr Forsvars- ochsakerhstssystemGrindsjons forskn ingscentrum14725 Tumba

FOI, Swedish Defence Research AgencyDefence & Security, Systems andTechnology

SE-147 25 Tumba


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SammanfattningI militara fordon anvands idag mer oeh mer fiberkompositer som strukturellt barandematerial for dess hoga styrka oeh laga vikt, Eftersom dessa farkoster kan hamna isituationer dar de beskjuts maste det ballistiska skyddet som strukturen gel' utredas. Dltstrukturen Ingar idet ballistiska skyddet maste ocksa resthallfastheten fOr strukturenutredas for att veta vad den har for egenskaper efter paverkan av angreppet.For att undersoka det ballistiska skydd som strukturella fiberkompositer ger har enstudie genomforts dar dels tre olika fibermaterial oeh dels tre vavtyper med olika gradav krimp jamforts med varandra. Fibrerna som provats ar tva vanligt anvanda fibrer;E-glas oeh kolfiber men aven den relativt nya basaltfibern. De tre olika vavtyperna somundersokts iir plainvav, satinvav oeh krimpfri yay, alIa av E-glasfiber. Matrisen somanvandes for aU tillverka samtliga laminat var DION 9102 vinylester.Laminaten gjordes iv a olika tjoeklekar av varje material genom vakuuminjicering oehefterhardades minst ett dygn i55-60C.Skjutforsok gjordes for att bestamma v50 for alia paneierna med en FSP pa 1,1 g.Dragprov oeh fiberhaltstester gjordes for varje material oeh resthallfastheten provadesgenom att aven gora dragprov p a ballistiskt skadade provstavar. Skjutforsoket visadeatt kolfiberlaminaten hade ea 25% hogre v50 an lamina ten gjorda av E-glasfiber medjamforhar ytvikt. Studien visade ocksa en liten okning p a 5-8% av v50 for Iaminatenmed de vavda E-glasfiber oeh den krimpfria bas altfibern jamfort med den krimpfriaE-glasfibetvaven. Dragstyrkan has en skadad provstav minskade, med de dimensionersom provstavarna hade i denna studie var minskningen iegel 20-30%.

Nyckelord: v50, ballistiskt skydd, krimp, fiberkompositer, resthallfasthet

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SummaryThe use of fibre reinforced plastics (FRP) is increasing more and more, especially as astructural material in military vehicles where a high strength and a low weight structureis preferred. As these vehicles must be designed to withstand a given ballistic impactthe FRP structure's own ballistic protection must be investigated. The structure alsohas to keep its load-carrying abilities after a ballistic impact, to ensure that the vehicledoes not break from a localized damage in the structure.To investigate the ballistic protection of structural FRPs a study was performed withthree different fibre materials and with three fabric types with different degree of crimpcompared to each other. The fibres compared are E-glass, carbon and basalt fibre andthree different E-glass weaves; a non-crimp fabric, a plain weave and a satin weave.The matrix used to make all of the laminates is a DION 9102 vinyl ester.The laminates were made by vacuum infusing in two different thicknesses for eachmaterial. They were post-cured in an oven for 24 hours with a temperature of 55-60 C.Ballistic tests with a 1.1 g fragment simulating projectile (FSP) were done to decidev50 for the different laminates.A fibre volume fraction test and tensile tests with and without damage from ballisticimpact were done to investigate the properties of the laminates. Results from theballistic limit testing show that the carbon FRP had about 25% higher v50 than anE-glass FRP. The tests also reveal a small increase of 5-8% in v50 for both the wovenE-glass laminates and the basalt fibre laminates compared to the E-glass with the NCr.The tensile strength tests show a decrease of about 20-30% on a damaged test samplewith the dimensions used in this study.

Keywords: V50, ballistic protection, degree of crimp, residual strength, wovencomposite

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Table of Contents1 Introduction 71.1 Background 71.2 Objective 8

2 Literature Review 92.1 Ballistic Impact 92.1.1 Phase 1 102.1.2 Phase 2 102.1.3 Phase 3 102.2 Ballistic Properties 11

3 Materials 133.1 Fibres and Matrix 133.2 Fabric Types 133.3 Stacking Sequence 163.4 Manufacture 174 Methods 204.1 Laminates 204.1.1 Areal Density 204.1.2 Thickness 204.1.3 Fibre Volume Fraction 204.2 Tensile Test. 214.3 V50 Ballistic Limit Testing 234.4 Post Ballistic Impact Tensile Test 25

5 Results 275.1 Laminates 275.2 Tensile Test. 285.3 V50 Ballistic Limit Testing 315.4 Post Ballistic Impact Tensile Test 35

6 Discussion 386.1 Materials and Manufacture 386.2 Methods and Results 39

7 Conclusions 428 Future work 43

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9 References 44Appendix A - Areal Density and Thickness; Sample

Measurements and Results 46

Appendix B - Fibre Volume Fraction; Sample Measurements andResults 50

Appendix C- Tensile Test; Sample Measurements and Results 51

Appendix D - V50BL(P); Time Measurements and Results 59

Appendix E - Post Impact Tensile test; Measurements andResults 66

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1 Introduction1.1 BackgroundThe weight of vehicles is of the outermost importance. It's not hard to see that less weightgives a lower power requirement and lower fuel consumption which is good both for theenvironmental and economic foot print of a vehicle. The obvious way to save weight is toalter the structural arrangement, either by optimizing the structural geometry, by changingmaterial or using both methods. This is why fibre-reinforced plastics (FRP) has become apopular material. A FRP consists of a fibre and a matrix, where the low density and highstrength of certain fibres and the load distribution capacity of the matrix makes it anexcellent material for high demanding structural applications [1]. One major area for FRPis military vehicles, where airplanes, ships and ground vehicles should endure harsherloading conditions than vehicles for the civil sector. The Swedish Navy corvette Visby is agreat example where the use of carbon fibre FRP for the hull structure instead ofaluminium saved almost 50% of the hull weight [2].The two most common fibres for structural applications are E-glass and various carbonfibres, where E-glass is the dominating fibre as reinforcement in composites due to its lowcost and good properties while carbon fibre with superior mechanical properties and lowerweight is chosen for high-performance applications [1]. A relative new interesting fibre isbasalt which may compete with E-glass or carbon as it is presented to have bettermechanical properties than E-glass and be cheaper than carbon fibre [3].While FRPs for structural applications are stiff, light and excellent at static loads, they areless effective at impact loads. Impact loads can be categorized in three groups, slowvelocity impact, high velocity impact and hyper velocity impact [4], where the slowvelocity impact could be a falling tool, the high velocity impact a projectile from a weaponand the hyper velocity impact are jets from shape-charge warheads or space debristravelling at several kilometres pel' second. Knowledge about the first case is important toensure that the vehicle is robust and not sensitive to normal wear and tear and everydayusage. The second case is very important as it ensures the ballistic protection of the crewand other vital systems against ballistic threats. The last case of hyper velocity impactssuch as shape-charge warheads are hard to counteract, thicker and more advanced armouron the vehicle is needed.FRP are often used as ballistic protection, either as body armour or as armour added ontothe structure. This is an easy way to add protection but at the cost of weight. Aramid fibresare often used as armour, familiar ararnid fibres are Kevlar made by Du Pont [5] andTwaron made by Teijin Aramid [6]. The reason is its good ballistic properties - it has ahigh toughness and damage tolerance which makes it excellent at absorbing energy 1].Another fibre used in ballistic armour is polyethylene fibre with ultra-high modulus weight(PE-DHMW); Dyneema made by DSM [7] and Spectra made by Honeywell [8]. PE-UHMW fibres have similar mechanical properties as aramid fibres but have a lowerdensity making its specific strength and E-modulus comparable to carbon fibres [1]. Themajor drawback of these two fibres are their lacking ability to function as a structural FRP,aramid fibres have a low longitudinal compressive strength, polyethylene fibres haverelatively low temperature tolerance and both of them have poor matrix compatibility.Inorder to save weight and still have enough protection on the vehicle, it is important toknow how much protection the structure gives and how much more protection is needed.A disadvantage with having the structure as a part of the ballistic protection is the damageand reduced strength of the structure after an impact.

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1.2 ObjectiveWith the background in mind it is clear that a better knowledge of the ballistic propertiesof structural FRPs would make it possible to manufacture a lighter and more cost-efficientstructure which contributes to the ballistic protection of the vehicle. Therefore the goal ofthis study is to see how three different fibre materials, E-glass, carbon and basalt comparesto each other. The two first are commonly used and the later could in the future be used forstructural FRPs. This study will also investigate how the fabric structure influence theballistic protection by comparing two E-glass weaves; plain weave and satin weave withdifferent degree of crimp to a non-crimp (NCF) E-glass fabric.

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2 Literature ReviewA literature survey was made on the subjects of this study. The majority of the search wasmade in databases through the KTH library using the Metasearch function. The databasesused were Inspec, Compendex Metadex and Scopus. Additional literature was receivedfrom FOI. The main search subjects were ballistic impact testing, ballistic properties ofcomposites, woven fabrics in composites, effect of crimp on composites and comparisonsofE-glass, carbon and basalt fibre.

2.1 Ballistic ImpactThe moment before a projectile strikes a target composite plate it has a certain velocityand mass. The energy or momentum has to be absorbed by or transferred to the target toavoid perforation. When perforation occurs it is said that the ballistic limit is reached. Toestablish the highest velocity at which the protective structure always stops the projectileis difficult and expensive, i.e. consumes lots of time and material. Instead the v50 ballisticlimit (v50BL) is often used. This term is the velocity at which the probability ofperforation is 50% [9).To understand which mechanical properties that contribute to the ballistic protectiveproperties of the material the energy absorbing mechanisms can be studied. The impact ofa blunt projectile may be described in three different phases, see Figure 1 [10J.

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Phase 1: 1Phase 2: 2Phase 3: 3-4

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F igu re 1 . T his figu re sho ws a sch em atic th re e ste p p ro ce ss o ve r th e d iffe re nt p hase s w hich o ccu rsu nd er a b allistic im pa ct o n a th ic k fib re -re in fo rce d co mp os ite b y a rig id , b lu nt cy lin dric al p ro je ctile . T hefig ure is re dra wn fro m 1 0].

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The impact ofa projectile on a fibre laminate has been investigated in [10-15] and showsthat several mechanisms contribute to the energy absorption. These mechanisms affectsvarious regions in the composite in different phases, see Figure 2.Primary yams Projectile

Secondary yarns

Region A RegionB

Figure 2. View over the affected area of a ballistic impact The primary and secondary yarns aredefined and two different damage regions are shown, region A is the area directly under the projectileand region B is the rest of the damaged area. Redrawn from reference [13].During the whole impact event in-plane matrix cracking and delamination between thelayers may occur. Also as the projectile penetrates and moves further into the target,frictional resistance and heat generation is an energy absorbing factor.

2.1.1 Phase 1When the projectile hits the target the fibres starts to fail by compression in region A. Asthe impact proceeds the material flow is dominantly in the thickness direction but can alsooccur in the radial direction. The material flows towards the impact point which leads tothe deformation along that direction. This phenomenon is called reverse bulge formationon the front face. The compressive stress generated directly under the face of the projectilegenerates radial tension in the surrounding area, i.e. region B.2.1.2 Phase 2As the projectile penetrates deeper the tension generated from phase 1 exerts pressure onthe fibres in region B and thus compressive deformation also develops in this region. Asthe compression wave proceeds and reaches the back-face of the composite, deformationstarts to appear as a cone formation. This bulge formation is therefore called coneformation.

2.1.3 Phase 3High stresses are created at the point of impact and the material at the edge of theprojectile is sheared. This can result in a plug of material which is pushed forward by theprojectile. The bottom layers are eventually broken by tension from the cone formationand the projectile with the plug exits from the back face of the target. This plugging effectis known as shear plugging.

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2.2 Ballistic PropertiesLiterature on ballistic testing is quite common but it is sometimes hard to compare theresults to each other. Manufacturing technique, materials in the composite and projectilescan all differ from test to test making it hard to find comparable results.Merriman and Miner [16] did ballistic testing on a Kevlar 29 basket 2/2 weave, a S-2 glasswoven roving', an E-glass woven roving and a SPECTRA 1000 plain weave compositewith two different matrices, PVB2 phenolic resin and polyester. The ballistic tests weredone with a .22 calibre, 17 grains fragment simulating projectile (FSP). The results fromtheir v50 tests are shown in Figure 3. Kevlar and Spectra outperforms S-2 and E-glasswhereas the S-2 glass laminates has better ballistic protection than laminates made fromE-glass.

1200

1000

800

"V;'-s 60 00U" I>400

20 0

0

t t J : : : I - J : :I --f- ---_-- I I . : : 1 : : _ 1 . : ~ : -+-t-f-f- _ 1 - - _ : - : : : : : : : : :~ ~ - = =- r r + - - ----f- --- --I J 1- _ o j - . 1 - - - - - - - 1 I k : f l - - -- - -"~j--+-1+-t-j--TTT------f- -[ -I - + + + r - - + - - - - - i 2 t v I-v"'" -----t- ~ -~t~-~:-_ ~ = - l ~- - : : - t t - + - - ~ ~ G ty~ =~~ _ :-:rr--t - - t - - I -~ ~ - = F : - - --------~I.::~~tl]J I - - I - - f < - I I

r-r- - - 1 : - _ - - - - 1 - - - _- ~~-I---f~_I-- I i i - l-l- -- :f-r- -l --i' : t f J f I . P f - ~ - _ - : - , V I +t I I II-+-+--~I- - + - - - ~ - - ! = G ~ - - - 1 - - 1 " " ~ ' - -+- Kevlar 29/JsopolyesterI--+-+-+-+-v_"~:;:~ -- - - ~ ~ - r l' .....-' 1 = - - ~ ] = Kevlar 29/PV8-PhenolicI-+-+-+-I-:.-.~? .....-' : : : : " : : : ; ; : v r f- 1 - --+- S-2/lsopolyester~ j 1 ~ _ " " ~ ~ ~ ~ ~- ~- ~ = - F = = _ I ~ - - + - ~ - } :-S-2/PVBPhenolic~ 1 + + ~ ----1-+- ---::-l- I t ~ -E-glass/!sopolyester= ~ : J _ : ~ H +: _ _ ~ = J _'_I~_L_= __j ~ : ,-,1- - t ~ -+ _ """-E-glass/PVB-Phenolic. . . . ::':_~L _ -_ - c- ~ _ -- - ~ r - - ! - + : '"-'i,~-Spectra 1000/lsopolyester"T'T" I - 1 . . .

o 5 10 15 20 25 30 35Total areal density [kg/mA2]

Figure 3. Literature data from 16] showing v50 values for Kevlar 29, 8-2 glass, E-glass and Spectrafibre laminates.This literature data will be used to compare and evaluate the v50 results from this study,Impact on woven fabrics and the effect of crimp is modeled and compared to ballisticimpact test results in [17] and [18]. The tests were done using spherical steel projectilesagainst a plain woven Twaron fabric target and showed high energy absorption for lowvelocities and less energy absorption for higher velocities. The reason for this result is thatwith high impact velocities there is not sufficient time for the transverse deflection topropagate through the material, i.e. the energy absorbed is smaller than at lower velocities.A study on ballistic protection for composite structures by Faur-Csukat [19] includedseveral ballistic impact tests on different materials. The materials investigated were twodifferent carbon fibre (Hexcel) weaves; plain weave and a twill 2/2 weave, an E-gJassplain weave, a S-glass satin weave, an aramid (Havel composites) twill 2/ 2 weave and aDyneema twill 2/2 weave. The matrix used were two types of rigid epoxy and two types of

1 Roving - A long and narrow bundle of fibres.2 PVB - Polyvinyl Butyral is high tensi le strength, impact resistant and transparent

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flexible epoxy which were added to the fibre through a hand lay-up method and followedby compression moulding at a pressure of 20 bar. The ballistic tests were done with asmall bore projectile (.22 long rifle) and a big bore projectile (.357 Magnum). The testsresulted in higher energy absorption for the materials with the flexible epoxy matrix andthat a carbon fibre composite with a twill 2/2 weave has 10% higher energy absorptioncompared to a carbon fibre composite with a plain weave.

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3 Materials3.1 Fibres and MatrixThe fibre materials used to make the composite laminates were three different types ofE-glass fabrics, one carbon fibre fabric and one basalt fibre fabric. The fibres were infusedwith DION 9102 vinyl ester matrix to make the composites. The matrix was blended with2% Cobalt 9802 P, 0,5% DMA 9826, 2% peroxide 24 and 0,05% acetylaceton 9854 tostart the curing process. The latter prolongs the gel time; this is to enable the matrix to wetall fibres even in thick laminates before it starts to gel.The data for the fabrics can be seen in Table 1. As there will be two different thicknessesof the same material they well be denoted by and -A for the thinner and -B for the thicker.The mechanical properties of the matrix and the fibres are shown Table 2.Table 1. Mater ial data for the different fabrics.

Name of Areal Fibre Fabric Weight Fibre materialmaterial density directions type distribution in

[9/m2] [j fibre directions [% 1E-Plain 380 [0,90] Plain 52/48 (WarpM'eft) E-glass

20]E-Satin 680 [0,901 Satin 50/50 (\NarpM'eft) r21] E-QlassE-NCF 815 [45/-451 NCF 50/50 E-glassC-NCF 450 145/-45) NCF 50/50 Carbon T-700S 6KB-NCF 600 [45/-451 NCF 50/50 Basalt Rov

68-680/1 0 1 1 nt/ExtTable 2. Mechanical properties of fibres and matrix used in the composites [1,22-24].

Material Density Tensile strength E-modulus[ kg / m ] _ [MPa) [GPa]E-Qlass fibre 2600 2600 72Carbon fibre 1800 4900 230Basalt fibre 2700 3100 84Vinyl ester DION 9102 1050 79 3.4

3.2 Fabric TypesA fabric may consist of several layers offibres and layers in different angles. The fibresmust be kept together by some mechanism to prevent the fibre yarns separating and thelayers to slide upon each other. This is done by stitching or weaving the layers together,see Figure 4.

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(a) (b)

Figure 4. Fabrics with fibre layers in different angles can be held together by stitching (a) or byweaving (b). The horizontal lines on (a) is the stitching. On (b) it is seen that the horizontal andvertical fibres alternate between going over and under each other.A main difference in the techniques is that by stitching the fibres together they remainrelatively straight and in woven fabric the fibres will have waviness due to the weaving.This waviness is called crimp. In this study a fabric with straight fibres will be called anon-crimp fabric (NCF) and a woven fabric a weave as defined in [25].Weaves are a common type of architecture for a fabric and can be in various shapes andconfigurations 1]. A NCF has their layers of fibre placed on top of each other in thevarious angles, e.g. +450 and -45, see Figure 5. The weave has fibres in the longitudinaland transverse direction, also called warp and weft directions. The most common weave isthe plain weave which is the tightest possibly, the fibre bundles in the warp and weftdirections alternate between going over and under each other, see Figure 6a. The satinweave is a more flexible weave because it has fewer interlacing points, but at the cost ofbeing more complicated to weave. The weaves can vary, common satin weaves are 8 HS,5 HS and 4 HS, where 4 HS for example means a four harness weave. The numberindicates the number of yarns in the repeating unit; 4 HS means the fibres goes over oneyarn and under three, while 8 HS means the fibres goes over one yarn and under seven.This is illustrated in Figure 6b for a satin 4 HS weave.

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Figure 5. Non-crimp fabric textile with two layers illustrated. The fibre bundles are straight and placedon top of each other in different angles, +45and -45~

Figure 6. Schematic view of two different weaves, (a) plain weave and (b) satin 4H weave. Thelongitudinal fibres, called the warp fibres, are here shown as drawn lines and the transverse fibres,called the weft fibres, as dashed lines.It is important with all type of weaves to consider the interlacing yams [1], giving the fibrea waviness which can be measured as the weaves degree of crimp. Crimp will affect thefabric in the way that when it is loaded the fibre bundles or yarns will first straighten outbefore it actually starts to carry the loads. This results in a larger total deformation of thefabric and possibly a larger energy absorption, which may affect the ballistic protection.The degree of crimp is defined as the ratio between the projected length of the fibre and itsactual length and different woven fabrics will have different degrees of crimp [17J, seeFigure 7. The degree of crimp may also be estimated by approximating the curve of thefibre with a zigzag pattern and identifying the patterns wavelength and amplitude, seeFigure 8.

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Actual length, AL

. AL-PLcrImp = AL

tProjected length, PL

Figure 7. Because of the weaving the fibre is shaped like a wave. Crimp is defined as how muchlonger the actual length is compared to the projected length in per cent.

(a)

(b)

Amplitudelength

Figure 8. Crimp can be idealized as a zigzag pattern (a), where the wave length and amplitude (b) isused to calculate the degree of crimp.Crimp is not the only factor that influences the properties of a composite when usingweaves; another factor is the inter-yam friction. With higher friction, it becomes harder fora projectile to push the fibre yarns apart and thus the projectile has to break more fibres toperforate the fabric, i.e. absorbing more energy.

3.3 Stacking SequenceThe stack is the package of fibres which is infused with matrix to get a composite. Thenumber of layers, fibre angle of each layer and the material of each layer has to be chosento get the desired properties of the laminate.The layers of the fibre were cut in rectangles approximately 1200 11Ullx 630 mm. Thestack has to have a symmetric layup to avoid warping'' and to cancel out stresses when thelaminate is cured [26]. In other words, the layers have to be mirrored in respect of thestacks middle or neutral axis. For example a [45,--45,45, --45] layup is not symmetricwhile a layup of [45, --45, --45,45] is symmetric, see Figure 9 for a schematic view. To beable to compare the ballistic properties in a reasonable way, the laminates should have thesame fibre content. Thus the fibre areal density is the governing parameter whereas thetotal areal density of the laminate and the thickness comes second and third respectively.

3 W arping - A geom etrica l defe ct that tw is ts the cross -se ction, cause d by res idual s tres ses .

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Because of the different densities of the fibres and the variations in the fibre volumefraction the laminates will get when vacuum infused, these three criteria may not besatisfied at the same time. Firstly the fabrics do not have the same areal density whichcombined with symmetric layup criteria gives a slight difference in the areal density of tilelaminates. Secondly laminates with different fibre density gives laminates with differentthickness, e.g. a carbon fibre laminate with the same fibre areal density will get thickerthan a glass fibre laminate since carbon has lower density than glass.Two laminates of each material with different thickness were made. The desirablethicknesses were about 5 nun and 10 mm. This is to ensure that the ballistic limit is insidethe velocity span of the projectile delivery system used, a thin laminate requires a lowerspeed which may be hard to achieve and with a very thick laminate the projectile may notbe able to reach the velocity needed to perforate.

Figure 9. The layers in the stack should be placed symmetrically in respect of the neutral axis, here(a) shows a [45, --45, 45, --45] layup that is not symmetric while (b) with a layup of [-45, 45,45, -45]is.

3.4 ManufactureThe laminates in this study were made by vacuum infusion. This was done at the structureslaboratory at the Department of Aeronautical and Vehicle Engineering at the RoyalInstitute of Technology (KTH) in Stockholm. The equipment used was an aluminiumtable, vacuum pump with a matrix trap, precision scale and various tools for cutting andclamping.Before infusion the stack must be packed with different layers that help with distributingthe matrix, the detaching of the laminate and making the package air tight. The layers fromthe bottom to the top are seen in Figure 10 where the layers have been gradually shifted tothe side to enable an easier view. TIle base of tile package is a flat aluminium table, andthen comes two layers of distribution weave, one layer of release film, the laminate stack,one layer of release film, two layers of distribution weave and finally a plastic bag.

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Figure 10. This photo shows the layers in a package soon to be infused. First a flat aluminium tablesurface, then distribution weave, release film, the fibre stack, release film, distribution weave and ontop a plastic bag to seal it air tight.Before the plastic bag is sealed to the table, inlet tube, outlet tube and distribution tubesare secured inside of the package to make sure the tubes do not move out of place whenthe vacuum pump is turned on. The inlet tube is then connected to a container of matrixand the outlet tube to a matrix trap which is connected to the vacuum pump. When thepump is turned on all the air is drawn out from the package and the matrix is led from thecontainer through the inlet tube into the package of fibre. The fibres are wetted by thematrix and any excess matrix reaches the outlet tube and the matrix trap. The trap is thereto insure no matrix gets into the vacuum pump, see Figure 11 for a photo and Figure 12 fora schematic view over the infusion process.

Figure 11. View of the vacuum infusion process. The vacuum pump draws matrix from the plasticbucket, through the stack of fibres, here half way through and moving to the right, and then into thematrix trap, the blue container at the end of the table.

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Tube to theVacuum pump Outlet tube

Inlet tube

Figure 12. Schematic of the vacuum infusion process. The vacuum pump draws matrix from acontainer, through the stack of fibres and into the matrix trap.After the laminate is cured it was put into an improvised oven, made of a paperboard box,air heaters and a thermometer, see Figure 13. The laminate was then post-cured for aminimum of24 and maximum of36 hours in 55-60C.

Figure 13. An improvised oven to post-cure the laminates, they were post-cured for a minimum of 24hours in 55-60 'C.

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4 Methods4.1 Laminates4.1.1 Areal DensityAs previously noted in chapter 3.3 the first priority is to get the same fibre areal density,second priority the same total areal density and last the same thickness. The fibre arealdensity, PAl' was calculated with equation 1 by adding together the areal density for eachlayer in the laminate,

where 11, is the number of layers and P Ajl the areal density of each fibre layer.The total areal density of the laminates, PA' including the weight of the matrix wascalculated as the mean value of pieces cut out of the laminate, measuring the area andweight, see Appendix A and dividing them according to equation 2,

2

where 1 1 1 ; is the mass of the sample, ~ is the area of the sample, i denotes which sampleof laminate and j the total number of samples.

4.1.2 ThicknessThe thickness, h of each laminate was taken as a mean value of measured thicknesses atdifferent locations, on the laminate,

3where hi is the measured thicknesses on iplaces of the laminate and i is the numbermeasurement, with the standard deviation s according to

4where 11 is the number of measurements. See appendix A for measurements.

4.1.3 Fibre Volume FractionThe fibre volume fraction test is done to measure the fibre content of the laminate. Theresult is then used to compare the quality of the different laminates, higher fibre volumefraction results in a better laminate. The test is done according to the ASTM D 2584 - 68[27] standard with the exception that the carbon and basalt sample will be burned at atemperature of 450C instead of 565 DC.First the porcelain cup is burnt dry in an oven and three small samples approximately25 mm x 25 mm is cut from three different places on the laminate, see Figure 14. Thedimensions of the samples are measured and weighed together with the porcelain cup, seeappendix B.

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Figure 14. Three specimens from each laminate were cut out at the places of the white squares forthe fibre volume fraction test.

The fibre volume fraction is then calculated with the data from Table 12 in appendix Baccording to equation 5

5where W CIiP is the mass of the porcelain cup, W c + s is the mass of cup and sample, T~lIm isthe mass of the burned cup with the remains of the fibres, T ~ is the volume for eachsample and P fibre is the density of the fibre.

4.2 Tensile TestTo acquire the tensile strength, (J", strain, e , and the E-modulus, E, of the laminates atensile test was done. The test was done at the laboratory halls of the Department ofAeronautical and Vehicle Engineering using their electrical Instron 4505 100 kN, seeFigure 15a, and in the hydraulic ShenckHydroplus PSB250 250 kN machines.(a) (b)

Figure 15. (a) This is the setup in the Instron 4505 100 kN machine. (b) The sample with anextensometer on it is clamped and pulled apart at a speed of 2 mm/minute until failure.The first one is specially made for static tensile tests and the latter one is for dynamicaltests. The test follows the standard ASTM D 3039/d 3039M - 00 [28] and the test sampleswere prepared according to the standard, see Figure 16a. One exception is for the thickercarbon laminate, it was modified from (a) to (b) with a dog bone shape according toASTM D638 - 08, see Figure 16b [29]. See appendix C for the dimensions of eachsample. Tabs made of glass fibre composite were glued to the specimens to ensure that thespecimens did not fail by the influence of concentrated stresses near the edges of theclamps.

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(a) 250 [nun]

. 1 < . > > : - : - < - : . : < . > ::::::::::::::::::;}}:?: ::::::::::; 25 ~ ~ ~ r '" ., . .. . . : - ~ < . > : T . . - : . : . : > :-< )500/570R=76

(b) :::: , r \ ~ : : ~ : :. . ~ ~ : : J : : : : : : : : : > : r : : . : : : : . : . y : : .~ _ ~ I o O I I o l I I ~ ~ ~ ? , : { Q ::01,,;1_~~~~~65,5 125

Figure 16. Showing the dimension of the specimens used in the tensile testing. The diagonally linedarea is the tab, which has different length for the two specimen thicknesses. Redrawn from 29}.The setup for the tensile test in the machine is seen in Figure 15b. The displacementchanges with 2 nun/minute and the load, stress and strain is recorded until failure.Because of the possible fluctuations in the strain measurements due to the extensometernot being properly fixed on the sample the E-modulus of the laminate is manuallycalculated as the average slope of the stress-strain curve from the tensile test. This is donewith a combination of equation 6 for the E-modulus,

E=(F/A)/e=a/e, 6where F is the force and A is the cross area of the sample and equation 7

7which calculates the slope between two points giving an approximate value ofE-modulus.A micromechanics-based model of the laminates longitudinal E-modulus,

8is used to compare the test results to theoretical values, where v is the volume fractionbased on the results from chapter 4.1.3, f J is the efficiency factor depending on theamount offibres in the load direction [1], see Table 3 and the indexes f for fibre, m formatrix and I for longitudinal measurements.Table 3. Reinforcemeint efficiency factor [11.

Reinforcement type P JAllqned unidirectional reinforcement 1Bidirectional symmetric reinforcement 0.5Randomly in-plane arranged reinforcement 0.375Randomly in-space arranged reinforcement 0.2

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Other things to register are the mode and location ~ inside or at edge of grip area~ offailure. Failure at the edge of the grip area may conclude that the failure is affected by theclamping pressure.

4.3 V50 Ballistic Limit TestingThe ballistic limit testing was made at FOI Grindsjon following the standard MIL-STD-662F [9]. The ballistic limit in this standard is called v50 ballistic limit (protection) -v50BL(P) - which is the velocity of a projectile where it has a 50% probability toperforate the target and perforation is assessed by the state of a thin witness plate behindthe tested object. Itmay seem odd to choose a 50% probability as a ballistic limitespecially when itconcerns armour and protection. In this case a low probability of 1% oreven better a 0% probability of perforation would be to prefer but it would be a costly andtime consuming process. Therefore the ballistic limit of 50% probability is usually chosento compare different materials with each other.The test rig consists of a rigid metal beam with a gun and two light frames sensorsclamped to it. The laminate to be tested is clamped all a moveable metal frame at the endof the beam. The setup for the test is schematically viewed in Figure 17 and the maincomponents in the setup are seen in Figure 18. The gun is based all a Gevar m/966.5x55 mm rifle but with a smooth bore barrel. Each light frame consists of two lightsources and two light sensors where a light source and a sensor is one light screen. Thelight screen is able to detect the profile of a passing object and by logging the time at twolight screens, i.e. positions, a mean velocity can be determined. By adding a second lightframe the average loss of velocity per meter, 111055 ' can be calculated,

9where Sj and S2 are the distances between the light screens of the two light frames,1),2,3,4 is the time when the base of the projectile passes the four different light screens andI ) is the distance between the light frames centre points. The velocity at impact, lIlmp' isthen determined by subtracting the product of uID5.S and the distance between the target andthe second light frames centre point, 1 2 with the measured mean velocity of the secondlight frame,

10The projectile is a .22 calibre skirtless fragment simulated projectile used for ballistictesting, see Figure 19 with a weight of 17 grains, i.e. about 1.1 g and a Rockwell Chardness of30 [30].A transient recorder W+W TRA 800 is used to collect and analyse the data from the lightframes while Microsoft Excel and Matlab are used for the calculations. An example of thefour registered signals from a passing FSP are shown in Figure 20 [31].

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mm

Witnessplate

Figure 17. This is a schematic view over the ballistic test setup.

Light frame

Figure 18. The components of the ballistic test;a gun, two light frames, target laminate and a witnessplate which is held at the correct distance by a wooden frame.

l2.54 l 5.46

[mm]

(6.53) ,> 1Figure 19. A f ragment simulating projectile (FSP) is used in the ballistic testing as project ile. Redrawnfrom reference [30].

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To determine if the projectile has partially penetrated (PP) or completely penetrated (CP)according to the definition in standard MIL-STD-662F and other standards like STANAG2920 and STANAG 4164 the protection criteria is used. To decide ifthere was a completepenetration or not a 0.5 mm witness plate of aluminium 2024 is used as visual control. Theplate is mounted 150 mm behind the target and if any light can be seen through the witnessplate, then the target is completely penetrated. This ensures that even when the projectileonly partially penetrated the target there will be no undetected secondary fragments from itcausing any harm. The impact area of laminate and witness plate were marked andphotographed after each shot, to have the results in a chronologie order.To decide the v50BL(P) for a laminate a certain amount of complete penetrations andpartially penetrations are needed within a chosen velocity span. Normally four, six or tenimpacts in velocity spans of 18,27,30 or 38 mls are used, where half of the impacts arepartial and the other half are complete penetrations [32]. This study used a v50BL(P) withthe three highest velocities resulting in partially penetration and the three lowest velocitiesresulting in complete penetration within a velocity span of27 m/s. To locate the rightvelocity the up-and-down method was used; the test starts with an estimation of the v50and depending on the result, complete or partial penetration, the next velocity is altered upOf down with 30 m/s, Steps of 30 In/S are used until the result changes and the step is thenlowered to 15 m/s for subsequent shots. The up-and-down method continues to the pointwhere the number of complete and partial penetrations inside the velocity span is correctand the test is finished. The v50BL(P) is then calculated as the arithmetic mean value ofthe impact velocities, uimp , in this case six velocities, as in equation 11

v50 = ( 2 : : = l t l t m p , 1 ) / 6 . 11MHN1045101.2

--Ram 1 skarm1--Ram 1 skiirm2-- Ram2 skarm1

0.8 --Ram 2 sklirrn2

to 0.6c'W'" 0.4~'"~0 0.20 ---- -~~

-0.2

-0.4 .25 -20 -15 -10 5 0 5 10Ti d ()Js)

Figure 20. Signals from the four light screens from a passed projectile. By courtesy of P. Appelgren[31J.

4.4 Post Ballistic Impact Tensile TestTo investigate the post impact properties of the laminate, specimens with a hole from aprojectile were tested in a tensile test. The test was similar to the tensile tests described inchapter 4.2 but following the standard ASTM D 5766/D 5766M - 02a, for open holetensile testing on composites [33]. To simplify the hole made by the projectile with adrilled hole works quite good if the laminates have more than 50% of the fibres in theloading direction [34]. The strength of the damaged samples will be presented by means of

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net section strength". The difference compared to the ordinary tensile test will be thedimensions of the samples and that no tabs are necessary, see Figure 21. One importantdimension is the diameter of the hole, as the specimen should be wide enough to cancelout edge effect from the hole. Therefore according to the standard the width of thespecimen should be at least six times wider than the diameter of the hole, which is thesame as the projectile diameter 5.46mm. Most of the samples had a width of 40 mm, butsome were cut to the minimum width of33 mm to ensure failure, see appendix D for thedimensions of each sample.

212 mm

mill~33

- 5.46Figure 21. Specimen dimensions for the post impact tensile test differ from the ordinary tensile test.Tabs are not needed but the hole results in a wider specimen to avoid edge effects.

4 Net section strength - the strength that considers the reduction in net area caused by the hole.

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5 Results5.1 LaminatesThe aim was to lower the variations in parameters to as few as possible between thelaminates. Because composite manufacturing with vacuum infusion is a sort of handicraft,variations can occur between manufacturers. By ensuring that the laminates are made bythe same manufacturer and with the same resin the comparison between the laminates ismore accurate.The results of equations 1 and 2 in chapter 4.1.1 are seen in Table 4 and results of eachsample are shown in appendix A for the areal density and thickness and appendix B for thefibre volume fraction.Table 4. Results for the laminates from the vacuum infusion process, A and B denotes the twodifferent thicknesses.

Laminate Fibre areal Total areal density Average Fibredensity [ g l m 2 ] thickness and volume[ g l m 2 ] standard deviation fraction

[mm] [%]E-Plain-A 6460 8884 4.92 0.004 50.1E-Plain-B 12920 17020 9.47 0.002 50.3E-Satin-A 6800 8974 4.9 0,.07 50.9E-Satin-B 12920 17860 9.42 0.024 52.9E-NCF-A 6520 8442 4.53 0.033 53.4E-NCF-B 13040 17370 9.04 0.02 54.3C-NCF-A 6300 8599 6.06 0.O24 53.4C-NCF-B 12600 16720 11.52 0.038 54.8B-NCF-A 6000 7948 4.40 0.062 47.3B-NCF-B 13200 17250 9.29 0.06 49.8

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5.2 Tensile TestThe theoretical solution to the E-modulus uses the material properties from Table 1 andthe results from the fibre volume fraction test in Table 4 together with equation 8. Thesecalculated values together with the results presented as nominal mean values from tensiletest are seen in Table 5, the result for each sample and plots for all the test samples can beseen in appendix C.Table 5. Results for the laminates mechanical properties.

Material Theoretical Measured Measured Measured strainE-modulus E-modulus maximum stress at maximum[GPa] [GPal [MPa] stress [%]

E-PJain-A 19,8 19.6 436 2.02E-Plain-B 19,9 19.5 381 1.84E-SaUn-A 20,1 20.4 570 2.54E-Satin-B 20,8 20.5 479 2.14E-NCF-A 20,9 20.8 473 2.03E-NCF-B 21,2 21.0 437 1.93C-NCF-A 63,0 65.2 1130 1.77C-NCF-B 64,6 67.6 1003 1.50B-NCF-A 21,7 23.2 560 2.36B-NCF-8 22,6 21.4 477 2.25..Results where It IS clearly visible that the extensometer has slipped or III any other way

affected the results are discarded, see Figure 22, test sample 2 for C-NCF-A, as anexample where the strain and E-modulus are discarded but the maximum stress is notaffected.

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1200--Sample 1--Sample 2

1 0 0 0 --Sample 3--Sample 4--Sample 5

8 0 0roQ_~fh 6 0 0I/}2 : ' :U ;

4 0 0

1.5Strain%]

2 2.5 3

Figure 22. Stress and strain results from the tensile test of the C-NCF-A samples. On sample 2 theextensometer has clearly slipped and the strain values are not valid.The failure mode did differ depending on the material. E-glass samples did have a cleanerfailure, often the fibres were torn apart at the same section while the basalt and carbonfibre samples had a more dramatic failure appearance, see Figure 23 and Figure 24.

Figure 23. From up to down, a E-Plaln-A, E-Satin-A and E-NCF-A sample after failure in tensileloading.

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Figure 24. From up to down, a C-NCF-A and B-NCF-B sample after failure in tensile loading. Bothmaterials showing a more dramatic failure, carbon fibre samples often had a violent exploding type offai lure whi le basalt had a slower failure with large delaminat ion.The tests made using the Instron 4505 machine were not affected by any clamping effectsbut the thicker samples requiring the Shenck Hydroplus PSB250 machine were affectedbecause of the hydraulic pressure clamping. The E-glass samples, see Figure 25, had somefailures in the clamping region while basalt and carbon did not, see Figure 26. This was aproblem especially for the E-Plain-B samples were all samples had failures that could betraced back to the clamping edges.

Figure 25. Samples tested in the Shenck Hydroplus PSB250 machine, the pressure from the clampsdid affect some samples at the edge of the tabs, circled area. From top down; E-Plain-B, E-NCF-Band E-Satin-B.

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Figure 26. Samples from tensile tests made in the Shenck Hydroplus PSB250 machine. There werenovisible effects of failure due to stresses from clamping edges on the samples made from carbonfibre, top in picture, and basalt fibre, bottom in the picture.

5.3 V50 Ballistic Limit TestingThe results from the light frames, t}~4, which equation 10 is based on, can be seen inappendix D. The recording was triggered by the third light screen, /3, which explains thenegative time results for 1 1 and tz -The test results of the v50BL(P) were calculated according to equation 10 with theresulting velocity span, see Table 6, but the individual results for each impact on thelaminates can be seen in appendix D.Table 6. This is the results from the V50BL(P) test for each laminate, with their test series name andthe final velocity span for the test (test limit spanwas of 27 m / s ) .

Material Test Average Total areal V50BL(P) Velocityseries5 thickness density [mts] span

[mm] [ g l m 2 ] [mts]E-Plain-A MHN1041 4.92 8896 351.92 16.6E-Plain-B MHN1044 9.47 16950 585.37 22.4E-Satin-A MHN1042 4.9 9000 346.28 23.9E-Satin-B MHN1045 9.42 17893 587.68 14.4E-NCF-A MHN1043 4.53 8457 325.55 22.3E-NCF-B MHN1046 9~04 17368 557.45 23.4C-NCF-A MHN1050 6.06 8593 410.0 21.5C-NCF-B MHN1048 11.52 16754 717.22 13.8B-NCF-A MHN1049 4.40 7941 343.62 21.3B-NCF-B MHN1047 9.29 17253 603~05 17.0The thinner laminates in general required more shots to achieve an acceptable result thanthe thicker ones, almost double the amount. This depends on the problem to adjust thevelocity of the FSP at low velocities. The firing system uses gun powder which in small

5 FOl notation

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amounts, i.e. at low velocities, makes it hard to control the explosion process inside thecartridge and therefore the scatter is larger. Another contributing factor could be that thevelocities were in the region of the speed of sound in air, affecting the velocity loss.All impacts on the laminates and witness plates were photographed, an example is seen inFigure 27 where a complete penetration of the E-NCF-B laminate is registered anddocumented with a photo of the laminate and witness plate.

Figure 27. Photograph documentation of the complete penetration of FSP number 17 on the ENCFBlaminate.

The damage zone from a FSP was generally larger on the thicker laminates, see Figure 28and for the laminates with woven fabric the zone was more circular without the outermostfibre delamination line the NCF laminates had, see Figure 29 and compare to Figure 28.

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Figure 28. Back face of the E-NCF-A (4,53 mm), left side photo, and the E-NCF-B laminate(9,04 mm), right side photo, showing a larger damage zone for the thicker laminate.

Figure 29. The visual damage zone for woven composites (E-Satin-B, 9,42 mm to the left andE-Plain-B, 9,47 mm to the right) differs from composites made with NCF, these are circular andwithout any extended delamination in the fibre direct ion.The effect of woven composite can also be seen in Figure 30, where the FSP only haspartially penetrated the laminate and has remained ShICk inside.

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Figure 30. Top is FSP stuck in a piece of the E-Plain-A and bottom a FSP stuck in the E-NCF-A. Asmaller delamination is seen in the woven composite. The FSP direction of motion before it stoppedwas downwards in the picture.In the top on the E-Plain-A sample it is possible to see the last layers that failed by tension.The bottom E-NCF-A sample in Figure 30, has a larger delaminated area and it is alsopossible to see reverse bulging formation on its front side, the first fibre layers that failedby compression.To compare the laminates the v50 results are plotted versus the fibre areal density and thetotal areal density, see Figure 31 and Figure 32 .

700

50 0~. . 40 0a~

30 0

20 0

10 0

8,0 10,0Fibre areal density [kg/mIl.2]

12,0,0 6,0

Figure 31. v50BL(P) compared against the fibre areal density of the different laminates.

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80 0

7 00

600

500~~,S 4000~300

200

100

06 12 14 1610

Total areal density [kg/mA2]Figure 32.The results from the v50BL(P)tests are compared against the total areal density of thedifferent laminates.

5.4 Post Ballistic Impact Tensile TestThe post ballistic impact tensile test results, based on four measurements, are seen inTable 7. For the result and plots on each sample see appendix E.Table 7. Results for the tensile test done on samples with a hole made by a perforating projectile.Material Theoretical Estimated Net section Strain at

Emodulus residual strength maximum[GPA] Emodulus [GpaJ [MPa] stress [% J

E-Plain-A 19.8 19.0 294 1.66EPlain-B 19.9 13.6 284 2.90E-Satin-A 20.1 19.9 395 2.37ESatin-B 20.8 15.6 387 2.47E-NCF-A 20.9 16.6 351 3.00E-NCF-B 21.2 18.9 320 2.40C-NCF-A 63.0 48.0 792 1.71C-NCF-W 64.6 69.6 867 1.31B-NCF-A 21.7 16.3 409 4.41B-NCF-B 22.6 20.4 371 1.82*ResuIts based on one sample.The asterix in Table 7 indicates that the C-NCF-B results were based on one sample. Forthis test the fibre layer in contact with the grip did delaminate at approximately 170 kN,making the sample slide inside the grip. Therefore the test serie was cancelled to save theremaining samples.The out of plane deformation was larger than in the ordinary tensile test, and sometimesaffected the extensometer, e.g. in Figure 33 sample 1, where the extensometer was placed

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in line over the hole and on the other samples itwas placed beside the hole to test thedi fference.

5 0 0

--Sample 1--Sample 2--Sample 3--Sample 4

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Figure 34. From left to right; two views over a E-NCF-8, E-Satin-8 and E-Plain-8 sample. The failureis right on top of the hole and across the width almost as a clean cut.

Figure 35. From left to right; two views over a 8-NCF-8 and C-NCF-B sample. The failure is acrossthe width at the hole but it is harder to see because of the more dramatic nature of the failure.

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6 Discussion6.1 Materials and ManufactureThe manufacture of the laminates did go according to plan, with the exception of beingmore time consuming than intended. Some problems were experienced with the basaltlaminates as they did not cure fully until they were post-cured. Therefore it is importantnot to open the package of composite, distribution weave, and release film until it has beenpost-cured or the result can be what is seen in Figure 36, where the package was at firstslightly opened and then the rest was removed after post-cure.

F igu re 36 . A ba salt lam ina te th at w as p artly o pe ned b efo re p ost curing , the lig hter are a to th e left, a ndth e re st w as o pe ned a fter fo ur da ys.

It seems like the matrix had not cured completely at the light area and needed some moretime. The distinct line between the light and dark area is where the release film was stillattached to the composite during post curing in room temperature.There were no problems with too long infusion time, the gel time with the blend ofaccelerators and inhibitor described in chapter 3.1 was about an hour and the infusion timewas around 20 minutes. To get these short infusion times on the thicker laminates largertubes were used, but at the cost of using a little more matrix.The goal was to make the different laminates with equal fibre areal density, area densityand thickness. Due to the fact that the fabrics had different fibre areal densities, therequirement for symmetric layup and the different material densities this was impossiblebut looking at the results of Table 4 the difference was only about 5% for the fibre arealdensities and about 7% for the areal densities. The difference in thickness was higher,almost 30%, mainly because carbon fibre have a lower density. If only considering the E-glass laminates the thickness difference is 8% which is most likely depending on the crimpof the weaves, as higher degree of crimp gives more space for the matrix to fill. Thisdifference between the areal densities could be avoided if the purchase of fabrics had beencoordinated and all had had the same fibre areal density. The thickness of the laminate diddiffer quite much along the surface due to the roughness of the surface. The estimatedstandard deviation of the thickness ranged from 0.002 mm for the EPlain-B laminate to0.062 mm for the B-NCF-B laminate. Something that should have been tested was thedegree of crimp on the weaves. This has not been done due to lack of proper measuringmethod and shortage of time. One method that was tried out was to take a photograph of athread upon a millimetre scale, but it was too hard to get the threads crimped profileperpendicular to the scale and the resolution of the photos was too low. One thing to noteis that the fibres in the plain weave are not evenly distributed, see Table 1. The warpdirection had 4% more fibres which affects the tensile strength as the samples were cut out

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in the warp direction. This problem could have been handled by doing a symmetrical lay-up but it was not discovered until after the vacuum infusion.

6.2 Methods and ResultsA problem which consumed a lot of time was that some of the laminates, the thicker testsamples, were too strong to be tested in the Instron 4505 machine usually used for tensiletests. Instead the stronger hydraulic Schenk Hydroplus PSB250 was used with mixedresults. Due to the compressive forces from the clamps acting on the sample as mentionedin chapter 4.2. the results were affected, especially regarding the E-glass laminates as theywere most sensitive to failure in the grip area. The C-NCF-B samples were modified to adog bone shape to ensure failure inside the machine's load range, this also helped to avoidthe clamping effect. There was a difference in the strength and strain between the differentthicknesses varying between 8% and 16% lower for the thick laminates. This could be aneffect from the clamping edges but as this difference is nearly equally large both forlaminates which failed in the grip area and those that did not, e.g. E-plain-B 12,6% and C-NCF-B 11,2% strength reduction, this was probably not a major affect. These problemscould have been avoided if all of the thicker samples were modified with a dog bone shapeor if there was enough samples to test and adjust the force of the clamping grips.The post impact tensile testing results were more scattered, but a few interestingcomparisons can be made from Table 7. First the difference between the thin and thicklaminates. The residual strength for the laminates did not differ so much, about 3-10%. Ifthe post impact tests, Table 7, are compared to the ordinary tensile tests, Table 5, there is ageneral drop from the ordinary strength to the net section strength of the laminate with20-30%, see Table 8.Table 8. Ratio of the net section strength compared to the max stress in the laminate.

Material Strength ratio [%] Strain ratio [%] E-modulus ratio [%1E-Plaln-A 67.4 82.2 96.6E-Plaln-B 74.5 157.6 69.7E-Satin-A 69.3 93.3 97.5E-Satin-B 80.8 115.4 76.1E-NCF-A 74.2 147.8 79.8E-NCF-B 73.2 124.4 90.0C-NCF-A 70.1 96.6 73.5C-NCF-B* 86.4 87.3 102.5B-NCF-A 73.0 186.9 70.3B-NCF-8 77.8 80.9 95.3"'Results based on one sample.

Table 8 also includes the ratio for the strain and E-modulus between undamaged anddamaged samples. The ratio for the strain is scattered but the E-modulus is generally lowerfor the damaged test samples.The C-NCF-B samples were not tested further as they started to delaminate in the griparea. Itwould help to make the grip area larger but that is not possible as the sample werealready cut out from the laminate. The grip pressure could maybe be adjusted but therewas not enough samples to test that.From the results in Table 6 it is seen that the v50BL(P) for laminates with woven fabricsand laminates with basalt fibre was about 5-8% higher than the E-NCF laminates while C-NCF laminates gave about 25% higher v50BL(P) than E-NCF for the same areal densities.

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The increase in v50 for the basalt and woven fabrics laminates is to small too concludethat either one is too prefer over ordinary E-NCF laminates. Too see how these resultscompare against v50 tests found in literature Figure 3 and Figure 32 are compared, seeFigure 37 for all the samples and Figure 38 for just the E-glass and basalt fibre results.Kevlar 29 and Spectra 1000 composites clearly have higher ballistic performancecompared to the other materials. The C-NCF laminates seems to have similar v50 asS-2 glass laminates and the results from the laminates made ofE-glass agree well with theliterature data. The results for the C-NCF may seem surprising as carbon fibre is generalknown to be sensitive to impacts but the Toray 700S fibre seems to be tougher and hasgood ballistic properties.

10 15 20 25 305Total areal densltv [kg/m~21

Figure 37. Comparison of the v50 results with the v50 results found in literature.

40

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6 10 16 18 2012 14rctal areal density [kgJm"2)Figure 38. A closer look at the comparison showing the v50 results for the E-glass and basaltlaminates with v50 results found for E-glass laminates in l iterature.

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7 Conclusions E-glass laminates with woven fabrics seems to have about 5-8% higher v50compared to NCF, but it is too low to cancel any other variations that could

contribute. Higher degree of crimp of weaves seems not to affect the v50 results. Basalt fibre laminates are slightly better than E-glass, about 5-8% increase in the

ballistic limit, but it is too low to cancel any other variations that could contribute. As a composite carbon fibre Toray 700S has the highest ballistic limit of the

studied materials, and from literature it is comparable to S-2 glass fibres. The damage, i.e. the delaminated region, for a laminate subjected to ballistic

impact is less with a woven fabric than with a NFC.

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8 Future workIt would be interesting to see the influence of woven fabrics studied further. This could bedone by having a set ofNCF, plain weave and satin weave from each material, too see ifthe small increase of 5-8% in v50 is consistent and if there is any difference between thetwo weaves. Another interesting thing to study would be to do thinner and thickerlaminates to see if the increase/decrease in v50 is linear, or if the thickness has somethingto do with the energy absorption, i.e. how the failure mechanism is different for differentthicknesses.

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9 References1 Astrom B.T., Manufacturing of polymer composites, chapter 1 and 2, 1997.2 Kockums, l i t t p :I/)\I\I'\\'. koc k um s.se/el ,lprodllcfs-seI1J icesllIaval -3/I //ace-s IIislsurface-COlli batalltslvisbv-class-col1 lettel, collected 2011-01-05.3 M. Burman, Basalt fiber - Li tteraturstud ie, KTH farkost och flygteknik, Stockholm2010-10-20.4 Siva Kumar K., Balakrishna Bhat T., Response of composite laminates on impact ofhigh velocity projectiles, Key Engineering Materials, v 141-143, pt.l ,pp 337-48, 1998.5 DuPont, http://www2.dllpont.comIKev/arlen USI, collected 2010-12-11.6 Teijin Aramid, http://www,teijinal'OlI1id.colJI/smartsife.dll's?id=20090, collected2011-01-05.7 Dyneema,11 f tp : lld l' l1eema . comlel / USlpu b lic ld vn ee ma lp a g ela b all IIM a feria I. 11//1 # 1 \ 1 a feria I -COl i t en (,collected 2010-12-11.8 Honeywell, http://wH.w51.honevwell.comlsmlaklprodllcts-deta isl0bel'.hIm /, collected2010-12-11.9 U.S. Department of Defense,V50 Ballistic Test for Armor, MIL-STD-662F, 1997.10 Naik N.K, Doshi A.V., Ballistic impact behavior of thick composites: analyticalformulation, AIAA Journal, v 43, n 7, pp 1525-1536,2005.11 Naik N.K., Shrirao P., Reddy B.C.K., Ballistic impact behaviour of woven fabriccomposites: Formulation, International Journal ofImpact Engineering, v 32, n 9,pp 1521-1552,2006.12 Naik N.K., Shrirao P, Reddy B.C.K., Ballistic impact behaviour of woven fabriccomposites: Parametric studies, Materials Science and Engineering A. v 412, n 1-2, pp104-116,2005.13Naik N.K., Shrirao P., Composite structures under ballistic impact, CompositeStructures, v 66, n 1-4, pp 579-590, 2004.14 Navarro C., Simplified modelling of the ballistic behaviour of fabrics and fibre-reinforced polymeric matrix composites, Key Engineering Materials, v 141-143, pp 383-400, 1998.15 Xiao-dong Cui, Tao Zeng, Dai-ning Fang, Study on ballistic energy absorption oflaminated and sandwich composites, Key Engineering Materials, v 306-308, pp 739-44,2006.16 E.A. Merriman, L.B. Miner, Fragmantation Resistance of Fiber Reinforced BallisticStructures, 10th International Symposium on Ballistics, San Diego, CA, USA, 1987.17 Tan V.B.C., Shim V.P.W., Zeng X., Modelling crimp in woven fabrics SUbjected toballistic impact, International Journal ofImpact Engineering, v 32, n 1-4, pp 561-574,2005.18 Shim V.P.W., Tan V.B.C., TayT.E., Modelling deformation and damagecharacteristics of woven fabric under small projectile impact, International Journal ofImpact Engineering, v 16, n 4, pp 585-605, 1995.19 Faur-Csukat, G., Development of composite structures for ballistic protection, ScienceFOnlm, v 537-538, pp 151-159,2007.

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http://www2.dllpont.comikev/arlenhttp://www%2Cteijinal%27oli1id.colji/smartsife.dll's?id=20090,http://wh.w51.honevwell.comlsmlaklprodllcts-deta/http://wh.w51.honevwell.comlsmlaklprodllcts-deta/http://www%2Cteijinal%27oli1id.colji/smartsife.dll's?id=20090,http://www2.dllpont.comikev/arlen


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20 a.Angeloni, glass woven fabric data sheet VV-380 P, Adress: a.Angeloni sri via AbateTommaso , 72!A5 - 30020 Quarto d'Altino (VE) - Italy, Tel: +390422823801 -780580Fax: +39 0422 782782, E-Mail: info@g-angelonLcolll21 a.Angeloni, glass woven fabric data sheet VV-770, Adress: a.Angeloni srI via AbateTomrnaso , 7 2 JA 5 - 30020 Quarto d'AItino (VE) - Italy, Tel: +390422823801 -780580Fax: +39 0422 782782, E-Mail: info@g-angelonLcolll22 Torayca, T 700S, http://wH.w.torarc[a.com/pdts!F700SDataSheet.pd{. collected2010-12-12.23 Basaltex, Technical Data SheetRov 68-680/l0/IntlExt.24 Riechhold, Product bulletin, DION 9102 epoxy based vinyl ester resin.25 Textilordlista, Standardiseringskommisionen iSverige (SS 25 10 15), Tekniskanomenklaturcentralen (TNC 76),1981, ISBN 91-7196-0776-726 D. Zenker! M. Battley, Foundation of Fibre Composites, Paper 96-10, 2:nd edition,2003, Stockholm27 ASTM, Standard Test Method for Ignition Loss of Cured Reinforced Resins,Designation: D 2584 -68.28 ASTM, Standard Test Method for Tensile Properties of Polymer Matrix CompositeMaterials, Designation: D 3 0 3 9 1 D 3039M - 00.29 ASTM, Standard Test Method for Tensile properties of Plastics, Designation: D638-08.30 U.S Department of Defense, Detail specification projectile, calibers .22, .30, .50, and20 nun fragment-simulating projectile, MIL-DTL-46593B, 2006.31 P. Appelgren, Hastighetsavtagandet for 1,1 g FSP, FOI Memo 3481,2011.32 A. Tyrberg, M.Nilsson, J. Ottosson, Standardiserat forfarande vid bestamning avgranshastighet for skydd, utgava 0.9, FOI-R--2321 --SE, 2007.[33] ASTM, Open Hole Tensile Strength of Polymer Matrix Composite Laminates,Designation: D 5 7 6 6 1 D 5766M - 02a.34 S. Kazemahavazi, D. Zenkert, M. Burman, Notch and strain rate sensitivity of non-crimp fabric composites. Composites Science and Technology, v 69, i6, pp 793-800,2009.

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Appendix A - Areal Density and Thickness;Sample Measurements and ResultsTable 9. Measurements for the areal density tests and results calculated as the arithmetic mean valueof five specimens for each laminate.

Material Width [mm] Height [mm] Weight [g] Areal Average arealdensity density [g /m2][g /m21

EPlainA 23.62 24.74 5.15 8813EPlainA 24.95 24.44 5.33 8741EPlainA 24.82 24.8 5.51 8952 8884EPJain-A 86.1 172.09 133.04 8979E-Plain-A 86.09 165.5 127.29 8934

Material Width [mm] Height [mm] Weight [g] Areal Average arealdensity density [g /m2][g /m2]

ESatin-A 24.52 24.25 5.2 8745E-Satin-A 24.81 24.98 5.55 8955ESatin-A 24.47 24.74 5.39 8903 8974E-Salin-A 98.13 154.47 138.68 9149E-Satin-A 98.1 154.37 138.04 9115

Material Width [mm] Height [mm] Weight [g] Areal Average arealdensity density [g/m 2 1[g lm2]

E-NCF-A 25 24.31 5.13 8441E-NCF-A 24.33 24.13 4.82 8210E-NCF-A 25.01 24.9 5.29 8495 8442E-NCF-A 80.55 162.9 112.12 8545E-NCF-A 76.52 163.14 106.35 8519

Material Width [mm] Height [mm] Weight [g] Areal Average arealdensity density [g /m2][g /m2]

C-NCF-A 24.65 24.44 5.2 8631C-NCF-A 24.76 25.91 5.52 8604C-NCF-A 24.45 24.5 5.17 8631 8599C-NCFA 101.92 113.38 98.22 8500C-NCF-A 87.57 184.15 139.14 8628

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Material Witdh [mmJ Height [mmJ Weight [gJ Areal Average arealdensity density [ g / m 2][ g / m 2]B-NCF-A 23.62 24.19 4.43 7753B-NCF-A 23.67 24.55 4.63 7968B-NCF-A 24.41 22.93 4.59 8201 7948B-NCF-A 116.08 134.88 123.58 7893B-NCF~A 120.27 131.33 125.17 7925

Material Witdh [mm] Height [mmJ Weight [g] Areal Average arealdensity density [g/m 2 J[ g / m 2]E-Plain-B 24.41 24.9 10.56 17374E~Plain-B 23.06 24.84 9.89 17266E-Plain-B 25.07 24.72 10.71 17282 17022E-Plain-B 109.12 193.03 327.57 15552E-Plain-B 111.37 111.4 218.79 17635

Material Witdh [mm] Height [mm] Weight [gJ Areal Average arealdensity density [ g / m 2][ g / m jE-Satin-B 24.7 24.16 10.48 17562E-Satin-B 24.15 24.87 10.65 17732E-Satin-B 24.78 24.44 10.82 17866 17858E-Satin-B 108.02 107.65 209.9 18051E-Satin-B 116.25 110.9 233.11 18082

Material Witdh [rnm] Height [mm] Weight [g] Areal Average arealdensity density [g/m 2 J[ g / m j _E-NCF~B 25 25.04 10.82 17284E-NCF-8 24.97 24.35 10.47 17220E-NCF-8 25 25.1 11.09 17673 17373E-NCF-8 88.35 101.88 156.4 17376E-NCF-8 86.36 125.41 187.5 17312

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Material Witdh [mm] Height [mm] Weight [g] Areal Average arealdensity density [g /m2 ][g /m2 ]

C-NCF-B 26.6 24.83 10.82 16382C-NCF-B 25.35 24.48 10.39 16743C-NCF-B 25.08 25.38 10.62 16684 16724C-NCF-B 91.14 97.82 150.38 16868C-NCF-B 107.04 111.38 202 16943

Material Witdh [mm] Height [mm] Weight [g] Areal Average arealdensity density [g fm2 ][g lm2 ]

B-NCF-B 23.94 24 9.99 17387B-NCF-B 24.65 24.95 10.48 170408-NCF-B 23.96 24.19 10.04 17323 17252B-NCF-B 99.79 109.05 187.8 17258B-NCF-8 97.29 179.7 301.66 17254

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T ab le 1 D . M e as ure me nt 1 -6 fo r th e th ic kn es s c alc ula tio n.

Material Thickness mesurement 1-6 [mm]E-Plain-A 4.88 4.92 5.01 4.90 4.78 4.80E-Satin-A 4.98 4.93 4.92 4.89 4.86 4.91E-NCF-A 4.52 4.59 4.36 4.49 4.42 4.47C-NCF-A 5.90 5.90 5.90 5.83 5.83 5.998-NCF-A 4.24 4.21 4.19 4.27 4.16 4.17E-Plain-B 9.37 9.25 9.28 9.25 9.36 9.41E-Satin-B 9.42 9,38 9.50 9.39 9.33 9.57E-NCF-B 8.73 9.23 8.81 8.75 8.93 8.99C-NCF-B 11.30 11.24 11.40 11.07 11.24 11.46B-NCF-8 B . 9 6 8.93 8.97 9.02 9.03 9.03

T ab le 1 1. M ea su re m en t 7 -1 1 a nd re su lts fo r th e th ic kn es s c alc ula tio n.

Material Thicknes mesurement 7-11 [mm] Average thicknessand standarddeviation [mm]

E-Plain-A 4.89 4.91 4.95 4.86 4.93 4.92 0.004E-Satin-A 4 . B 2 4.89 4.90 4.87 4.95 9,47 0.002E-NCF-A 4,52 4.43 4.58 4.48 4.64 4,9 0.007C-NCF-A 5,99 6.13 6.18 6.25 6.20 9.42 0.024B-NCF-A 4,20 4,18 4.60 4.58 4.57 4.53 0.033E-Plain-B 9.46 9,30 9,60 9.64 9,55 9,04 0.02E-Satfn-B 9,57 9,62 9,37 9,45 9.87 6.06 0.024E-NCF-B 9.09 8,95 9,15 9,23 9,23 11.52 0.038C-NCF-B 11,38 11.43 11,73 11,79 11.85 4.40 0.0628-NCF-8 8,99 9.00 9.58 9,45 9.50 9,29 0,06

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Appendix B - Fibre Volume Fraction;Sample Measurements and ResultsTable 12. Here is the measured volume, weight of porcelain cup, weight of cup and sample, weight ofcup and remaining fibres after burning and the result for the fibre volume fraction for each sample.

Material V [cm3] WCUD [g] Wcs [g] Wbum [9] v,[%]E-NCF-B 5.73 28.96 39.78 37.07 54.4E-NCF-B 5.61 28.64 39.11 36.5 53.9E-NCF-B 5.79 29.45 40.54 37.65 54.5E-NCF-A 2.78 28 33.13 31.86 53.4E-NCF-A 2.63 26.07 30.89 29.73 53.5E-NCF-A 2.89 26.48 31.77 30.47 53.1C-NCF-B 7.75 26.05 36.87 33.64 54.4C-NCF-B 7.32 26.48 36.87 33.72 54.9C-NCF-B 7.54 29.45 40.07 36.91 55C-NCF-A 3.72 28 33.2 31.57 53.3C-NCF-A 4.01 28.63 34.15 32.46 53.1C-NCF-A 3.71 25.73 30.9 29.33 53.9E-SATIN-B 5.59 26.06 36.54 33.85 53.6E-SATIN-B 5.68 29.44 40.09 37.33 53.4E-SATIN-B 5.98 28.62 39.44 36.64 51.6E-SATIN-A 2.91 27.99 33.19 31.81 50.5E-SATIN-A 3.02 26.47 32.02 30.53 51.7E-SATIN-A 3.00 25.72 31.11 29.66 50.5E-PlAIN-B 5.83 26.05 36.61 33.7 50.5E-PlAIN-B 5.52 29.45 39.34 36.61 49.9E-PlAIN-B 5.92 25.71 36.42 33.5 50.6E-PlAIN-A 2.89 28 33.15 31.73 49.6E-PLAIN-A 2.96 28.63 33.96 32.52 50.5E-PLAIN-A 3.03 26.47 31.98 30.44 50.4B-NCF-B 5.50 26.06 36.05 33.44 49.7B-NCF-B 5.81 29.45 39.93 37.28 49.9B-NCF-B 5.51 27.99 38.03 35.38 49.8B-NCF-A 2.63 25.72 30.15 28.99 468-NCF-A 2.66 28.64 33.27 32.04 47.3B-NCF-A 2.56 26.48 31.07 29.83 48.5

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Appendix C - Tensile Test; SampleMeasurements and ResultsTable 13. Measurements and results for each sample done in the tensile test. 'po' means that thevalue was not representat ive and was discarded.

MaterialfSample Witdh Thickness E-modulus Maximum Strain at[mm] [mm] [GPa] stress maximum

_LMPa] stress [%}E-Plain-A1 24.55 4.89 187 438 2.11E-Plain-A2 24.3 4.8 199 414 1.77E-Plain-A3 25 4.9 198 445 2.11E-Plain-A4 24.8 4.9 195 457 2.16E-Plain-A5 24.5 4.8 199 424 1.94E-Satin-A1 24.5 4.95 199 526 2.52E-Satin-A2 24.4 4.9 198 555 --E-Satin-A3 24.51 4.84 214 590 2.61E-Satin-M 24.3 4.9 203 595 2.37E-Satin-A5 24.5 4.9 207 586 2.68E-NCF-A1 24.4 4.45 205 479 2.09E-NCF-A2 24.06 4.47 209 475 2.02E-NCF-A3 23.7 4.4 212 483 2.07E-NCF-M 24.25 4.41 213 453 1.88E-NCF-A5 24.4 4.48 203 477 2.11C-NCF-A1 22.23 5.95 682 1139 1.76C-NCF-A2 22.65 5.85 - - 1155 - -C-NCF-A3 22.81 5.88 642 1108 1.76C-NCF-A4 22.89 5.89 643 1096 1.69C-NCF-A5 22.85 5.8 643 1148 1.85B-NCF-A1 24.5 4.2 221 540 2.43B-NCF-A2 24.49 4.1 - - 572 - -B-NCF-A3 24.7 4.18 223 588 2.63B-NCF-A4 24.65 4.28 222 572 2.38B-NCF-A5 24.81 4.14 260 531 1.99E-Plain-B1 23.9 9.41 194 414 1.99E-Plain-B2 24.56 9.64 193 353 1.78E-Plain-B3 24.89 9.33 200 393 1.88E-Plain-B4 24.91 9.55 195 347 1.66E-Plain-B5 24.79 9.46 195 400 1.9E-Satin-B1 23.85 9.41 209 476 2.2E-Satin-B2 23.67 9.4 188 536 2.38E-Satin-B3 23.9 9.6 193 455 2.08

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MaterialfSample Witdh Thickness Emodulus Maximum Strain at[mm] [mm] IGPa] stress maximum

[MPa] stress [%]ESalinB4 24.5 9.6 236 478 1.97ESatinB5 24.06 9.6 200 449 2.06ENCFB1 24.69 8.95 215 416 1.78ENCFB2 24.7 8.85 215 428 1.82ENCFB3 24.66 8.82 204 452 2ENCFB4 24.77 8.86 214 446 1.98ENCFB5 24.81 8.76 203 445 2.07CNCFB1 15.05 11.46 69.6 1008 1.54CNCFB2 15.64 11.39 70 1023 1.46C-NCF-B3 14.26 11.39 68.6 1055 1.56CNCF-B4 14.85 11.43 65.9 962 1.46C-NCF-B5 15.63 11.27 65.6 969 1.48B-NCF-B1 24.7 8.83 172 453 2.5B-NCF-B2 24.54 8.89 189 499 2.658-NCF-B3 24.56 8.81 268 473 1.62B-NCF-B4 24.37 8.89 241 485 2.06B-NCF-B5 24.49 8.85 200 473 2.43

E-Plain-A

600I--.-----.-----,----,---;:::==:c:==~--Sample 1--Sample 2

500 --Sample 3" --Sample 4--SampJe5400ro :f/,2::; 300(I) ~~ .p(j) '"200~

100 ?J/00 0.5 1 1.5 2 2.5 3

Strain% ]

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E-Plain-B

60 0 r--.----.----,------,-----;::::==::c::=====0

c o0..'$:::. 300tiltile(j)

5 0 0

/4 0 0

2 0 0

1 0 0

--Sample 1--Sample 2--Sample 3--Sample 4--Sample 5

2 3. 5 1 1.5Strain% ]

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E-Satin-A

-- Sample 1-- Sample 2---- Sample 3--Sample 4--- Sample 5

0. 5 1 1.5Strain [% ]

2 3

E-Satin-B

G O O

roCL2-; - 300(/)~(j)

1 1.5Strain [% ]

2 2.5 3

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E-NCF-A

G O O

5 0 0

4 0 0(U0-~7: 30 0

IIIQ)l-U S200

/, ---S--,7 -- ample 1.p'~ -- Sample 2

/' --Sample3(y -- Sample 4y --Sample 5

/~

~/

2 2.5. 5 1 1.5Strain [% ]

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E-NCF-B

600~----~------~------~------~----~------~

00 0.5 1 1.5 2 2.5 3Strain% ]

C-NCF-A

1200 1 --Sample 1--Sample 21000 --Sample 3

--Sample 4--Sample 5

800r0-o . . .~ G O O/)U)


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CNCF-B

1000

120 0~-----.-------r------'-------r-j=====~s~a:m:p~le~1~---Sample 2--Sample 3--Sample 4--Sample 5

800til0 . . .: ; :( / } G O O(/}eW

4 0 0

2 0 0

0.5 1 1.5Strain% ] 2 2.5 3

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B-NCF-A

-- Sample 1--Sample 2-- Sample 3-- Sample 4--Sample 5

0 . 5 1 1.5Strain {% ]

2 2.5 3B-NCF-B

7 ~J7.:~ / r"/// - -S-a-m-p-Ie-1I, /.-/ _.// -- Sample 2} /,// ../ _- Sp~y//. __ sample 3; / ample 4, -- Sample 5

100 ~vh i '~I

o ~ _~=-- _ _L0 . 5

roQ_:2 :-;;; 3 00ID0>in

1 1.5Strain [% J 2 2.5 3

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Appendix D - V50BL(P); TimeMeasurements and ResultsTable 14.Measurements and results for each fired projectile for the V50BL{P) test. An asterix meansthe result was discarded, usually due to a yawed projectf1e or no data were recorded.

Material Test_nr tl [ms] t 2 [ms] t 3 [ms] t4[ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[m / s]E-Plain-AMHN1041 001 0 0 0 0 pp *

MHN1041 002 -2.33604 -1.55836 0.01536 1.33384 CP 373.3MHN1041 003 -2.86404 -1.90992 0.01828 1.63372 pp 305.3MHN1041 004 -2.79484 -1.86372 0.01788 1.59408 PP 312.5MHN1041 005 -2.32732 -1.55252 0.01496 1.32832 CP 374.8MHN1041 006 -2.65216 -1.76888 0.01572 1.51292 PP 328.7MHN1041 007 -2.62976 -1.75516 0.01588 1.49916 PP 331.8MHN1041 008 -2.58292 -1.72368 0.01568 1.47364 PP 337.6MHN1041 009 -2.68756 -1.79288 0.01716 1.53248 PP 324.5MHN1041 010 -2.33496 -1.55796 0.01484 1.332 CP 373.7MHN1041 011 -2.44248 -1.6294 0.01596 1.39448 CP 357.0MHN1041 012 -2.75612 -1.83784 0.01888 1.57136 PP 317.7MHN1041 013 -4.54724 -3.03244 0.0338 2.58812 PP *MHN1041 014 -2.47768 -1.65276 0.01712 1.41832 PP 350.7MHN1041 015 -2.36424 -1.57668 0.01624 1.35068 CP 368.8MHN1041 016 -2.4064 -1.60508 0.01532 1.37476 CP 362.0MHN1041 017 -2.4713 -1.6484 0.Q168 1.4112 CP 352.8MHN1041 018 -2.5602 -1.709 0.0151 1.4609 PP 340.4MHN1041 019 -2.3162 -1.5451 0.0149 1.3224 CP 376.6MHN1041 020 -2.4607 -1.6417 0.0157 1.4043 PP 354.3MHN1041 021 -2.1896 -1.461 0.0144 1.2497 CP 398.2MHN1041 022 -2.2215 -1.4823 0.0155 1.2711 CP 391.5MHN1041 023 -2.4467 -1.6327 0.0157 1.3962 CP 356.3

*Result is discarded.

Material Test_nr tl [ms] t 2 [ms] t3[ms] t4[ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity[m / s]

E-Plain-BMHN1044 001 -1.3855 -0.9248 0.0085 0.7914 CP 627.9MHN1044 002 -1.4598 -0.9742 0.0102 0.8349 CP 595.7MHN1044 003 -1.5743 -1.0505 0.0103 0.8999 PP 552.4MHN1044 004 -1.5398 -1.0275 0.0103 0.8794 PP 565.1

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Material Test_nr ti [ms] t 2 [ms] t3 [ms] t 4 [ms] Impact Calculatedcharacteristic Impact[CPtPP] velocity[mts)E-Plain-B MHN1044 005 -1.5172 -1.0129 0.009 0.8656 PP 573.7

MHN1044 006 -1.5159 -1.0115 0.0104 0.8672 PP 573.3MHN1044 007 -1.469 -0.9806 0.00915 0.8386 CP 592.1MHN1044 008 -1.4933 -0.9964 0.0102 0.8543 PP 582.4MHN1044 009 -1.7799 -1.1878 0.0109 1.0164 PP 489.1MHN1044 010 -1.463 -0.9766 0.009 0.8355 CP 595.0MHN1044 011 -1.3976 -0.9327 0.01 0.7996 CP 622.7MHN1044 012 -1.3747 -0.9179 0.0084 0.785 CP 632.5MHN1044 013 -1.4011 -0.9354 0.0088 0.8007 CP 620.5MHN1044 014 -1.3893 -0.9273 0.0089 0.7931 CP 626.2

Material Test_nr t1 [ms] t 2 [ms] t3 [ms] t4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity[m/slE-Satin-A MHN1042 001 -2,6619 -1.7766 0.0157 1.5162 PP 328.3

MHN1042 002 -2.4542 -1.637 0.0161 1.402 CP 355.2MHN1042 003 -2.6375 -1.7594 0.0173 1.5061 PP 330.5MHN1042 004 -2.538 -1.6967 0.0129 1.4507 PP

, .MHN1042 005 -3.2614 -2.1737 0.0216 1.8599 PP 268.7MHN1042 006 -2.3491 -1.5675 0.0147 1.3402 CP 371.2MHN1042 007 -2.3997 -1.6008 0.0158 1.3701 CP 363.2MHN1042 008 -2.4865 -1.6584 0.0161 1.4213 CP 350.1MHN1042 009 -2.6928 -1.7955 0.019 1.5372 PP 324.4MHN1042 010 -2.5965 -1.7324 0.0166 1.4814 PP 335.8MHN1042 011 -2.453 -1.6364 0.0156 1.4009 PP 355.2MHN1042 012 -2.6314 -1.7554 0.0167 1.5032 PP 331.3MHN1042 013 -2.7593 -1.8403 0.0187 1.5763 PP 316.4MHN1042 014 -2.4895 -1.6609 0.0159 1.4213 CP 350.1MHN1042 015 -2.2105 -1.4748 0.0142 1.2622 CP 394.4MHN1042 016 -2.6628 -1.7759 0.017 1.5201 PP 327.5MHN1042 017 -2.1233 -1.4169 0.0135 1.2129 CP 410.1MHN1042 018 -2.3207 -1.5491 0.0141 1.3253 CP 375.0MHN1042 019 -2.0996 -1.4006 0.0138 1.1994 CP 414.6


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Material Test_nr tl [ms] t 2 [ms] t3 [ms] t4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity[ m / s ]E-Satin-8 MHN1045 001 -1.4552 -0.9713 0.0096 0.8313 CP 598.0

MHN1045 002 -1.5315 -1.0225 0.008 0.8727 PP 568.9MHN1045 003 -1.4623 -0.9761 0.009 0.8351 CP 595.2MHN1045 004 -1.5851 -1.0574 0.0108 0.9073 PP 548.4MHN1045 005 -1.4525 -0.9696 0.009 0.8287 CP 599.3MHN1045 006 -1.4768 -0.9858 0.0091 0.8432 CP 589.3MHN1045 007 -1.4875 -0.9929 0.0091 0.8494 PP 584.5MHN1045 008 -1.4801 -0.9882 0.0093 0.8459 CP 587.0MHN1045 009 -1.5592 -1.0408 0.0104 0.8908 PP 558.1MHN1045 010 -1.4925 -0.9943 0.014 0.8619 PP 580.8MHN1045 011 -1.5155 -1.0092 0.0156 0.8769 PP 571.8MHN1045 012 -1.4708 -0.9803 0.0134 0.8489 PP 589.3MHN1045 013 -1.383 -0.9211 0.0131 0.7989 CP 626.3MHN1045 014 -1.3868 -0.9239 0,0128 0.8007 CP 625.5MHN1045 015 -1.3549 -0.9028 0.012 0.7823 CP 639.5MHN1045 016 -1.3503 -0.8999 0.0116 0.779 CP 641.1

Material Test_nr tl [ms] t2 [ms] t3 [ms] t 4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity[m / s]E-NCF-A MHN1043 001 -2.4601 -1.6411 0.0151 1.4055 CP 353,8

MHN1043 002 -2.4728 -1.6499 0.0154 1.4113 CP 352.5MHN1043 003 -2.4454 -1.6312 0.0162 1.3967 CP 356.4MHN1043 004 -2.4267 -1.6191 0.0149 1.3842 CP 359.5MHN1043 005 -2.3992 -1.6011 0.0168 1.3754 CP 360,9MHN1043 006 -2.5928 -1.7301 0.0158 1.4789 CP 336.3MHN1043 007 -2.6285 -1.7528 0,018 1.5007 CP 331.7MHN1043 008 -2.4899 -1.6609 0.0162 1.4228 CP 349.4MHN1043 009 -3.036 -2.0253 0,0208 1,7359 PP zMHN1043 010 -2.5091 -1.6738 0,0159 1.4321 CP 347.4MHN1043 011 -2.9185 -1.9467 0,0197 1.6643 PP 299.9MHN1043 012 -2.7085 -1.8063 0,0184 1.5465 PP 322.4MHN1043 013 -2.495 -1.6644 0,0159 1.4245 CP 349,5MHN1043 014 -3.1873 -2.1248 0,0242 1.8197 PP 274.7MHN1043 015 -3.9543 -2.6361 0,0273 PP *MHN1043 016 -4.6527 -3.1008 0,0305 PP zMHN1043 017 -3.5027 -2.3385 0,0204 1.9914 PP *

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Material Test_nr t1 [ms] t2 [ms] t3 [ms] t4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[ m / s ]E-NCF-A MHN1043 018 -2.7635 -1.8435 0.017 1.5763 pp 316.0

MHN1043 019 -3.0808 -2.0549 0.0202 1.7565 pp 284.0MHN1043 020 -3.0838 -2.0565 0.0221 1.7596 pp 283.8MHN1043 021 -2.7698 -1.8485 0.0182 1.5859 pp *MHN1043 022 -2.7861 -1.8576 0.0194 1.5881 pp 314.1MHN1043 023 -2.6223 -1.7493 0.017 1.4968 CP 332.8MHN1043 024 -2.2611 -1.5082 0.0154 1.2917 CP 385.3MHN1043 025 -2.9249 -1.9513 0.0197 1.6684 PP 299.3MHN1043 026 -2.1353 -1.4251 0.0134 1.2196 CP 407.9MHN1043 027 -2.0653 -1.3784 0.0128 1.1793 CP 421.5MHN1043 028 -2.1943 -1.4639 0.0143 1.2528 CP 397.2

"'Result is discarded.Material Test_nr t1 [ms] t2 [ms] t3 [ms] t4 [ms] Impact Calculated

characteristic Impact[CP/PP] velocity[ m / s ]

E-NCF-B MHN1046 001 -1.3348 -0.8892 0.0124 0.7711 CP 649.3MHN1046 002 -1.6015 -1.0666 0.0158 0.9267 PP 540.4MHN1046 003 -1.4713 -0.9803 0.0135 0.8501 CP 588.6MHN1046 004 -1.5101 -1.0059 0.0145 0.8732 CP 573.9MHN1046 005 -1.5227 -1.0141 0.0148 0.8809 CP 569.0MHN1046 006 -1.6226 -1.0806 0.0163 0.9391 PP 533.3MHN1046 007 -1.5864 -1.0564 0.0157 0.9178 PP 545.6MHN1046 008 -1.5214 -1.0141 0.0133 0.8783 CP 569.3MHN1046 009 -1.5646 -1.0421 0.0154 0.9055 PP 553.0MHN1046 010 -1.5264 -1.0168 0.0143 0.8821 CP 567.7MHN1046 011 -1.6125 -1.0738 0.0153 0.9324 PP 537.3MHN1046 012 -1.5624 -1.0408 0.0149 0.9036 CP 554.0MHN1046 013 0 0 0 0 *MHN1046 014 -1.5613 -1.0398 0.0148 0.9021 PP 555.4MHN1046 015 -1.3904 -0.9263 0.0129 0.8031 CP 623.3MHN1046 016 -1.4527 -0.9678 0.0135 0.8392 CP 596.5MHN1046 017 -1.3365 -0.8905 0.0121 0.7717 CP 648.1MHN1046 018 -1.3959 -0.93 0.0129 0.8063 CP 620.6


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Material Test_nr t1 [ms] h[ms] t3 [ms] t 4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[m/s]C-NCF-A MHN1050 001 -2.0738 -1.3791 0.0249 1.2053 CP 417.6

MHN1050 002 -1.9951 -1.3278 0.0225 1.1579 CP 434.0MHN1050 003 -2.1911 -1.4564 0.0293 1.2775 PP 394.5MHN1050 004 -2.1627 -1.4376 0.0276 1.2595 PP 400.1MHN1050 005 -2.0296 -1.3505 0.0237 1.1796 PP 426.2MHN1050 006 -2.1246 -1.4131 0.0264 1.236 CP 407.5MHN1050 007 -2.0024 -1.3328 0.0223 1.1618 CP 432.4MHN1050 008 -2.1001 -1.3966 0.0258 1.2211 CP 412.6MHN1050 009 -2.1842 -1.4519 0.0287 1.2735 PP 396.1MHN1050 010 -1.9165 -1.2759 0.0208 1.1107 CP 451.9MHN1050 011 -2.0151 -1.3409 0.0226 1.1692 CP 429.9MHN1050 012 -2.0513 -1.3646 0.0239 1.1908 CP 422.5MHN1050 013 -2.0641 -1.3731 0.0243 1.1993 CP 419.8

Material Test_nr t1[ms] t2 [ms] t3 ems] t4[ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[mts]C-NCF-8 MHN1048 001 -1.3004 -0.8667 0.0113 0.7495 PP 667.2MHN1048 002 -1.6028 -1.0676 0.0156 0.9262 PP 540.8

MHN1048 003 -1.3275 -0.8847 0.0114 0.7659 PP 653.1MHN1048 004 -1.1969 -0.7976 0.0101 0.6896 CP 724.5MHN1048 005 -1.244 -0.829 0.0105 0.7169 PP 696.8MHN1048 006 -1.1916 -0.7944 0.0099 0.6864 CP 727.7MHN1048 007 -1.2032 -0.8019 0.Q105 0.6937 PP 720.8MHN1048 008 -1.1861 -0.7904 0.0104 0.6844 CP 730.6MHN1048 009 -1.2134 -0.8088 0.0102 0.6995 CP 714.7MHN1048 010 -1.7186 -1.1443 0.0171 0.9935 PP 504.3MHN1048 011 -1.2038 -0.8022 0.0103 0.6938 PP 720.5MHN1048 012 -1.0969 -0.7312 0.0089 0.6318 CP 790.2MHN1048 013 CP *MHN1048 014 -1.6534 -1.1013 0.0162 0.9555 PP 524.3MHN1048 015 -1.2297 -0.8196 0.0099 0.7087 PP 705.1MHN1048 016 -1.2197 -0.8129 0.0101 0.7027 PP 710.7MHN1048 017 -1.186 -0.7906 0.00995 0.6831 CP 730.8MHN1048 018 -1.1687 -0.7789 0.00971 0.6741 CP 741.6MHN1048 019 -1.2177 -0.8119 0.01 0.7011 CP 712.1MHN1048 020 -1.1463 -0.7639 0.0098 0.661 CP 756.2

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*Result is discarded.Material Test_nr t1 [ms] t2 [ms] t3 [ms] t4 [ms] Impact Calculated

characteristic Impact[CP/PP] velocity[m / s]

8-NCF-A MHN1049 001 -2.2839 -1.5171 0.0336 1.3376 CP 378.1MHN1049 002 -2.6566 -1.7711 0.0186 1.5238 pp 327.7MHN1049 003 -2.9397 -1.9581 0.0208 1.683 pp 297.6MHN1049 004 -2.4366 -1.6135 0.0505 1.4506 CP 352.3MHN1049 005 -2.8426 -1.8957 0.0196 1.6281 pp *MHN1049 006 -2.8899 -1.9267 0.0223 1.6579 pp 301.9MHN1049 007 -2.4036 -1.5926 0.0453 1.4232 CP 358.0MHN1049 008 -2.3059 -1.5311 0.0352 1.3526 CP 374.1MHN1049 009 -2.446 -1.6188 0.0534 1.46 CP 350.6MHN1049 010 -2.4826 -1.6391 0.0653 1.4993 pp 343.9MHN1049 011 -2.6311 -1.7548 0.0188 1.5082 PP 331.0MHN1049 012 -2.3462 -1.557 0.0382 1.3795 CP 367.7MHN1049 013 -2.357 -1.5647 0.0386 1.3879 CP 364.7MHN1049 014 -2.409 -1.5967 0.0457 1.4264 CP 357.1MHN1049 015 -2.3592 -1.5658 0.0395 1.3884 CP 365.3MHN1049 016 -2.3668 -1.5704 0.0403 1.3946 CP 364.1MHN1049 017 -2.4746 -1.6367 0.061 1.4894 PP *MHN1049 018 -2.6179 -1.7456 0.0184 1.5006 PP 332.7MHN1049 019 -2.0531 -1.3654 0.0243 1.1931 CP 421.8MHN1049 020 -2.0928 -1.3918 0.0254 1.2175 CP 413.4MHN1049 021 -2.4425 -1.6173 0.0528 1.4558 CP 351.2MHN1049 022 -2.1558 -1.4334 0.0274 1.2556 CP 401.4

*Result IS discarded.Material Test_nr t1 [ms] t2 [ms] h [ms] t 4 [ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[m / s]8-NCF-8 MHN1047 001 -1.549 -1.0318 0.0145 0.8949 PP 559.5

MHN1047 002 -1.9114 -1.2723 0.0207 1.1083 PP 453.1MHN1047 003 -1.4498 -0.9661 0.0133 0.8373 CP 597.5MHN1047 004 -1.4182 -0.9452 0.0121 0.8187 PP 610.4MHN1047 005 -1.5655 -1.0426 0.0152 0.9052 PP 553.0MHN1047 006 -1.5222 -1.0174 0.0065 0.8685 PP *MHN1047 007 -1,4643 -0.9756 0.0133 0.8455 CP 591.8MHN1047 008 -1.5469 -1.0308 0.0144 0.8937 PP 559.9MHN1047 009 -1.4804 -0.9866 0.0128 0.8554 PP 585.4MHN1047 010 -1.4096 -0.9393 0.0122 0.8135 CP 614.5

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Material Test_nr tl [ms] t 2 [ms] t3[ms] t~ms] Impact Calculatedcharacteristic Impact[CP/PP] velocity

[m/s]B-NCF-B MHN1047 011 -1.4296 -0.9528 0.0125 0.8251 pp 606.5

MHN1047 012 -1.4497 -0.9665 0.013 0.8365 pp 597.6MHN1047 013 -1.4143 -0.9436 0.0091 0.8101 CP 614.6MHN1047 014 -1.4079 -0.9385 0.0126 0.8125 CP 615.7MHN1047 015 -1.3631 -0.9083 0.0119 0.7861 CP 635.8MHN1047 016 -1.3884 -0.9253 0.0122 0.801 CP 624.3

"'Result is discarded.

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Appendix E - Post Impact Tensile test;Measurements and ResultsTable 15. Measurements and results for each sample done in the tensile test. '--' means that thevalue was not representative and was discarded.

Tensile Witdh Thickness Net sectiontest [mm] [mm] strengthsample [MPa]E-Plain-A1 34.2 4.8 293E-Plain-A2 34.2 4.85 297E-Plain-A3 33.94 4.85 283E-Plain-A4 34.32 4.8 302E-Satin-A1 34.29 4.9 403E-Satin-A2 33.49 4.9 381E-Satin-A3 33.84 4.92 40

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Ballistic Impact Properties