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Numerical and Experimental Comparative Analysis of Ballistic Performance of Packages Made of Biaxial and Triaxial Kevlar 29 Fabrics

Pinkos Justyna, Stempien Zbigniew

Autex Research Journal

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2020

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Vol. 20, no. 2

203--219

EN

The objective of this study is a comparative analysis of the ballistic effectiveness of packages made of biaxial and triaxial Kevlar 29 fabrics under the hitting of Parabellum 9×19 bullet. We conduct both numerical simulations using the LS-Dyna program and experimental research in a ballistic research laboratory. Based on the comparative analysis of the results from the numerical and experimental research, demonstrated differences exist in the ballistic effectiveness between the packages made of biaxial fabrics and the packages consisting of triaxial fabrics. For this purpose, the residual velocity of the bullet is analyzed in detail in terms of the maximum deformation cone, the shape of the deformation cone, and the distribution of stress for the textile ballistic packages. It is established that the packages made of triaxial fabric show a considerably smaller deformation cone compared with the packages made of biaxial fabric, a more favorable shape of the deformation cone from the perspective of ballistic trauma and distribution of stress similar to materials with isotropic properties. Poorer properties are recorded for these packages in the case of the minimum number of layers necessary for stopping the bullet, which arises from the open-work structure of the fabric.

2

Microstructure characterization of 7055-T6, 6061-T6511 and 7A52-T6 Al alloys subjected to ballistic impact against heavy tungsten alloy projectile

Khan M. A., Wang Y., Malik A., Nazeer F., Yasin G., Khan W. Q., Ahmad T., Zhang H.

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1484--1496

EN

A spray formed 7055 Al alloy, and traditional formed 6061 Al and 7A52 Al alloy were subjected to extrusion. Later 7055Al and 7A52 treated with T6 and 6061 Al treated with T6511 heat treatment. To investigate the microstructure evolution by optical microscopy (OM), scanning electron microscopy (SEM), electron back scattering diffraction (EBSD) and X-rays diffraction pattern (XRD) analysis were employed to observe the variation in mechanical properties and damages patterns of single layered aluminum alloys impacted by heavy tungsten alloy (WHA) projectile. During impact a substantial increase in temperature inside the target material caused melting on crater wall. The hard metastable intermetallic compound and pores were produced on penetration path owing to diffusion of projectile particles and rapid melt re-solidification. These compounds enhance the hardness (600-650 HV0.1/10) in the middle deformed channels of 7055 Al alloy target. In addition, small size pores, whirl-pool and white adiabatic shear bands were observed in 7A52 and 6061 Al alloys, respectively. The variation in hardness and microstructure of Al alloys target was limited within the 2 mm area from the perforation path. 7055-T6 Al alloy has demonstrated better ballistic protection in terms of strength, mass efficiency (N), depth of penetration (DOP) and penetration path diameter in comparison of other Al alloys.

3

Certain Ballistic Performance and Thermal Properties Evaluation for Extruded Modified Double-base Propellants

Fahd A., Mostafa H. E., Elbasuney S.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

621--635

EN

The main advantages of modified double-base (MDB) propellants are wide range of burning rates, high energy output, as well as enhanced thrust. This study reports on the effect of potential oxidizers − potassium perchlorate (KP) or ammonium perchlorate (AP), stoichiometric binary mixture of the oxidizer (KP or AP) with metal fuel (Al), and energetic nitramine (HMX) on combustion characteristics of MDB propellants. MDB propellant formulations based on these additives, constituting 10 wt.% of total mass of the MDB formulation, were manufactured by solventless extrusion process. The impact of these additives on ballistic performance particularly the burning rate as well as on the characteristic exhaust velocity of gaseous product (C*), was evaluated using small-scale ballistic evaluation test motor. KP and AP exhibit different effects; KP positively impacts the burning rate, AP positively impacts C*. Stoichiometric binary mixture of AP/Al positively impacts both the burning rate and C*; HMX substantially enhances C*. These energetic additives could alter the combustion mechanism, by thinning the induction zone, allowing the luminous flame zone to be more adjacent to the burning surface. Therefore, the combustion reaction could proceed faster. The developed MDB propellant formulations were found to be more energetic with an increase in calorific value in comparison to reference formulation (using bomb calorimeter); they exhibited similar ignition temperature by means of cook off test. DSC measurements demonstrated similar onset and maximum decomposition temperature of developed MDB propellant formulations to reference DB propellant formulation but with an increase in total heat released (J/g).

4

The Effect of Different Copper Salts on the Mechanical and Ballistic Characteristics of Double Base Rocket Propellants

Abdel-Ghani N., Elbeih A., Helal F.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 2

469--482

EN

This paper discusses the enhancement in the ballistic performance of double base rocket propellants (DBRPs) by the addition of different copper salts vs lead salts as burning rate modifiers through stable combustion and the formation of a plateau region in the low pressure region. Compositions based on DBRPs containing different percentages of lead stearate and different types of copper salts were prepared and studied. For comparison, a conventional DBRP was studied. The ignition temperature and heat of combustion were determined experimentally, and the mechanical properties were measured and evaluated. The performance in terms of ballistic characteristics (burning rate, operating pressure) were measured at different throat diameters (8, 8.5, 9, 9.5 mm) and at different temperatures (−20 and 50 °C). Specific impulses were calculated using the ICT thermodynamic code. The experimental data from the proportional study indicate that the compositions containing the studied burning rate modifiers are superior to the original DBRP in respect of ballistic performance and mechanical properties.

5

Comparison of numerical and experimental study of armour system based on alumina and silicon carbide ceramics

Chabera P., Boczkowska A., Morka A., Kędzierski P., Niezgoda T., Oziębło A., Witek A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 2

363--367

EN

The main goal of this numerical and experimental study of composite armour systems was to investigate their ballistic behaviour. Numerical simulations were employed to determine the initial dimensions of panel layers before the actual ballistic test. In order to achieve this aim, multivariate computations with different thicknesses of panel layers were conducted. Numerical calculations were performed with the finite element method in the LS-DYNA software, which is a commonly used tool for solving problems associated with shock wave propagation, blasts and impacts. An axisymmetric model was built in order to ensure sufficient discretization. Results of a simulation study allowed thicknesses of layers ensuring assumed level of protection to be determined. According to the simulation results two armour configurations with different ceramics have been fabricated. The composite armour systems consisted of the front layer made of Al2O3 or SiC ceramic and high strength steel as the backing material. The ballistic performance of the proposed protective structures were tested with the use of 7.62 mm Armour Piercing (AP) projectile. A comparison of impact resistance of two defence systems with different ceramic has been carried out. Application of silicon carbide ceramic improved ballistic performance, as evidenced by smaller deformations of the second layer. In addition, one of armour systems was complemented with an intermediate ceramic-elastomer layer. A ceramic-elastomer component was obtained using pressure infiltration of gradient porous ceramic by elastomer. Upon ballistic impact, the ceramic body dissipated kinetic energy of the projectile. The residual energy was absorbed by the intermediate composite layer. It was found, that application of composite plates as a support of a ceramic body provided a decrease of the bullet penetration depth.

6

Numerical and experimental study of armour system consisted of ceramic and ceramic-elastomer composites

Chabera P., Boczkowska A., Morka A., Niezgoda T., Oziębło A., Witek A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 4

853--859

EN

The paper presents numerical and experimental results in the study of composite armour systems for ballistic protection. The modelling of protective structures and simulation methods of experiment as well as the finite elements method were implemented in LS DYNA software. Three armour systems with different thickness of layers were analyzed. Discretization for each option was built with three dimensional elements guaranteeing satisfactory accuracy of the calculations. Two selected armour configurations have been ballistically tested using the armour piercing (AP) 7.62 mm calibre. The composite armour systems were made of Al2O3 ceramics placed on the strike face and high strength steel as a backing material. In case of one ballistic structure system an intermediate ceramic- elastomer layer was applied. Ceramic- elastomer composites were obtained from porous ceramics with porosity gradient using pressure infiltration of porous ceramics by elastomer. The urea-urethane elastomer, as a reactive liquid was introduced into pores. As a result composites, in which two phases were interconnecting three-dimensionally and topologically throughout the microstructure, were obtained. Upon ballistic impact, kinetic energy was dissipated by ceramic body The residual energy was absorbed by intermediate composite layer. Effect of the composite shell application on crack propagation of ceramic body was observed.

7

Ballistic performance of FRP – steel layered structures

Barnat W., Gotowicki P., Dybcio P., Gieleta R., Kosiuczenko K.

Journal of KONES

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2013

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Vol. 20, No. 2

15--20

EN

In this study, the impact performance of layered structures made of aramid/epoxy, S2 glass/epoxy, Dyneema and steel subjected to high velocity impact is presented. All materials were previously examined using proper techniques of strength tests. The procedure allowed determining Young’s moduli, Poisson’s ratio, ultimate compression and tension strength, shear modulus. The ballistic test procedure was based on standards for testing panels and armour plates. For the purpose of ballistic tests, standard 5.56 NATO ammunition (183 g) was used. The aim of presented work was to determine ballistic performance of different structures under bullet impact. During the tests, subsequent time moments were recorded using Phantom V12 high-speed camera. When structure penetration did occur, the residual velocity of bullet was measured using PVM-21 lightscreen. Basing on the results, each material performance was evaluated. This paper reviewed a number of mechanisms that influence the ballistic performance of ballistic textiles. The composites reinforced with continuous fibres (aramid, S2 glass) could effectively absorb the kinematic energy of bullet. The efficiency of energy absorption for each types of material in the order from highest is as follows: polyethylene fibres Dyneema HB50, composite reinforced with S2 glass fibres, composite reinforced with aramid fibres.

8

Magnetorheological fluids as a prospective component of composite armours

Kozłowska J., Leonowicz M.

Composites Theory and Practice

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2013

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R. 13, nr 4

227--231

EN

Magnetorheological characterization of a synthesized MRF and ballistic performance of a MRF-composite material with high-strength textiles as Kevlar and Dyneema, are presented. The ballistic performance of the investigated structures under a Parabellum 9 mm projectile with a velocity of 360 m/s, on the basis of deformation depth in backing clay and number of pierced layers was determined. The targets with MRF demonstrate a 30% reduction in depth of deformation when comparing to the neat samples. On the other hand, implementation of the MRF to the structures of the high-strength materials caused a twofold increase in the overall target weight. At the same time, the inherence of the MRF in the structure of the composite samples does not affect the number of damaged layers. This result indicates that the absorbing mechanism of the MRF is rather limited to residual energy absorption under the impacting projectile.

PL

Wytworzono i przebadano ciecz magnetoreologiczną na bazie oleju syntetycznego i żelaza karbonylkowego. Opracowanej cieczy magnetoreologicznej użyto w konstrukcjach kompozytowych pancerzy ochronnych. Wytworzone pakiety poddano badaniom odporności na przebicie pociskiem Parabellum 9 mm o prędkości 360 m/s, w celu określenia możliwości ich wykorzystania w obszarze kompozytowych ochron balistycznych. Obecność cieczy MR w hybrydowych pancerzach z warstwami wysokowytrzymałych materiałów typu Kevlar lub Dyneema wykazała redukcję głębokości deformacji podłoża balistycznego o 30% w porównaniu do konstrukcji próbek bez cieczy. Z drugiej jednak strony zwiększenie odporności balistycznej kompozytowych konstrukcji z cieczą MR nastąpiło przy dwukrotnym wzroście masy całkowitej układu. Jednocześnie, obecność cieczy MR nie wpłynęła na zmianę liczby warstw przebitych w konstrukcjach próbek kompozytowych. Uzyskane wyniki świadczą o tym, że rola cieczy MR w absorbowaniu energii wytworzonych próbek ogranicza się w zasadzie do pochłaniania i rozpraszania resztkowej energii podczas oddziaływania pocisku z pancerzem.

9

Effect of Velocity of the Structure-Dependent Tension Wave Propagation on Ballistic Performance of Aramid Woven Fabricslication

Stempień Z.

Fibres & Textiles in Eastern Europe

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2011

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Vol. 19, no. 4 (87)

74--80

EN

One of the elements defining the effectiveness of soft ballistic protection is the geometric structure of the fabric. In previous research works it was proven that the geometric structure influences the propagation velocity of the tension wave. Thus, fabrics of a geometric structure ensuring a maximum propagation velocity of the tension wave should be selected for the ballistic packets of bullet-proof vests. In such a case, the area of deformation will be larger, which will diminish the probability of local destruction and the acuteness of the ballistic stroke on the user’s body. The aim of the research was to receive a ballistic packet containing layers of fabric ensuring a maximum propagating velocity of the tension wave and verification of its ballistic performance in terms of shooting through, maximum deformation and the ballistic stroke.

PL

Jednym z elementów decydujących o skuteczności miękkich osłon balistycznych jest struktura geometryczna tkaniny. We wcześniejszych badaniach wykazano, że struktura geometryczna ma wpływ na prędkość propagacji fali naprężeń. Istnieje zatem pełne uzasadnienie wyboru struktury geometrycznej tkaniny o maksymalnej prędkości propagacji fali naprężeń na warstwy pakietów balistycznych kamizelek kuloodpornych. W takim przypadku obszar objęty procesem odkształcania będzie rozłożony na większej powierzchni, co zmniejszy możliwość miejscowej destrukcji i wielkość udaru balistycznego na korpus użytkownika. Celem realizowanych badan było uzyskanie pakietu balistycznego zawierającego w swoich warstwach tkaniny o maksymalnej prędkości propagacji fali naprężeń oraz jego weryfikacja balistyczna uwzględniająca efekt przestrzelenia, maksymalną deformację oraz wielkość udaru balistycznego.

10

Glass fibre/polyester composites under ballistic impact

Barcikowski M

Kompozyty

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2008

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R. 8, nr 1

70-76

EN

This work presents results of ballistic impact tests on glass-fibre/polyester laminates. An effort has been made to manufacture composites with improved tolerance to ballistic impact using inexpensive, common materials like fibreglass and unsaturated polyester resin, by means of modern, yet popular moulding technology. Laminates were made using various E-type glass fibre reinforcements: chopped strand mat, continuous filament mat, cloth and two different woven rovings, with varying weight. Varying number of reinforcement layers were tested, as well as varying reinforcement-to-matrix ratio - from 20 to 60% vol. Samples of manufactured laminates were subjected to impact by a 3 g spherical hardened steel impactor moving at the velocity of 60 and 70 m/s (giving 5.4 and 7.35 Joules of kinetic energy, accordingly) using a gas gun test assembly. Samples were subsequently scanned using optical flat-bed scanner and the obtained images were digitally processed by software to measure the extent of delamination. Two ways of interpreting the extent of delamination in composites were tested - through the evaluation of delaminated volume and through the maximal delaminated surface area - to find usefulness of both methods. Impact energies were kept low such that none of manufactured laminates were perforated. The impact testing and image analysis of delaminated zone has shown similar range of damage in low-weight cloth and continuous filament mat, contrasted to inferior performance of chopped strand mat and high-weight, loose-structure woven rovings. Relationship between coherence of structure and delaminated area reduction has been shown. Unexpected three-dimensional shape of delaminated volume that had been found was discussed. Moreover, two methods of delaminated zone evaluation in composites subjected to impact - by means of delaminated volume and by means of delaminated area - has been discussed, suggesting superiority of the latter.

PL

Praca przedstawia wyniki balistycznych badań udarowych laminatów poliestrowo-szklanych. Wysiłki ukierunkowano na wyprodukowanie kompozytów o podwyższonej odporności na udar balistyczny, wykorzystując niedrogie, powszechnie stosowane materiały, takie jak włókno szklane i nienasycone żywice poliestrowe, przy użyciu nowoczesnej i jednocześnie popularnej technologii formowania. Laminaty wytworzono, wykorzystując wzmocnienie z włókna szklanego typu E w różnych postaciach: mat z włókien ciętych, mat pętlicowych z włókna ciągłego, tkaniny z jedwabiu szklanego oraz dwóch różnych tkanin rovingowych, różniących się gramaturą. Zastosowano zmienną ilość warstw poszczególnych typów wzmocnień oraz zmienny udział wzmocnienia w kompozycie - od 20 do 60% obj. Próbki wytworzonych laminatów poddano udarowi sferycznym impaktorem o masie 3 g ze stali utwardzanej cieplnie poruszającym się z prędkościami 60 i 70 m/s (co daje odpowiednio 5,4 i 7,35 J energii kinetycznej) z użyciem stanowiska badawczego typu działo gazowe (ang. gas gun). Następnie próbki poddano skanowaniu na optycznym skanerze płaskim, a uzyskane obrazy poddano cyfrowej analizie w celu określenia wielkości obszaru zdelaminowanego. Przetestowano dwa ujęcia ewaluacji obszaru zdelaminowanego - poprzez objętość zdelaminowaną oraz poprzez największe pole powierzchni delaminacji - w celu określenia przydatności obu metod. Energie udarów utrzymywano na niskim poziomie, tak że żadne z wytworzonych laminatów nie uległy perforacji. Wyniki badań udarowych i analizy obszarów poddanych delaminacji wykazały zbliżony poziom uszkodzeń w wyniku udaru u kompozytów wzmocnionych włóknem szklanym w postaci tkaniny z jedwabiu szklanego o niskiej gramaturze oraz maty z włókien ciągłych i słabszych od nich właściwości w przypadku kompozytów wzmocnionych luźnymi tkaninami rovingowymi o dużych gramaturach oraz matami z włókien ciętych. Wykazano zależność między zwartością struktury wzmocnienia a korzystnym ograniczeniem obszaru uszkodzeń delaminacyjnych kompozytów. Niespodziewany kształt trójwymiarowej objętości zdelaminowanej otrzymano i został on przedyskutowany. Przedyskutowano ponadto dwie metody oceny obszaru zdelaminowanego w kompozycie poddanym udarowi - pod względem objętości zdelaminowanej oraz powierzchni zdelaminowanej - sugerując wyższość drugiego ujęcia.