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Édio Pereira Lima - One of the best experts on this subject based on the ideXlab platform.
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effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Journal of materials research and technology, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Abstract Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification.
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Effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Elsevier, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification. Keywords: Ballistic test, Ceramic Armor, Multilayered Armor system, Impact geometr
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how effective is a convex al2o3 nb2o5 Ceramic Armor
Ceramics International, 2016Co-Authors: Sergio Neves Monteiro, Luis Henrique Leme Louro, Alaelson Vieira Gomes, Carlos Frederico De Matos Chagas, Aldelio Bueno Caldeira, Édio Pereira LimaAbstract:Abstract Ceramic materials are under increasing attention as a component in ballistic Armor, especially for protection against high impact energy ammunition. In multilayered Armors, a front Ceramic plate can dissipate more than 50% of the impact energy and investigations are continuously trying to increase this performance. This communication revealed, for the first time, how much impact energy is dissipated in an Al2O3–4 wt% Nb2O5 convex-curved surface Ceramic Armor by high velocity 7.62 mm ammunition. Both ballistic simulation and actual tests indicate a 16–18% superior performance of the convex-curved surface as compared to the flat surface Ceramic.
Ahmad Serjouei - One of the best experts on this subject based on the ideXlab platform.
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on improving ballistic limit of bi layer Ceramic metal Armor
International Journal of Impact Engineering, 2017Co-Authors: Ahmad Serjouei, Govind Gour, Sridhar Idapalapati, Xianfeng Zhang, Geoffrey E B TanAbstract:Abstract This paper investigates experimentally and numerically methods to enhance the ballistic performance of Ceramic Armor. Initially we demonstrate an experimental set-up to impose pre-stress to Ceramic-metal bi-layer Armor and study the depth of penetration to measure the ballistic efficiency as a function of pre-stress intensity validating our previous numerical studies on effect of pre-stress on the ballistic limit of Ceramic Armor (Int. Journal of Impact Engineering, 2015(84)159-170). Secondly, a module is designed and tested to achieve interface defeat in Ceramic Armor with multiple interface layers. Finally, influence of thickness of the steel cover plate (CP) on ballistic performance of SiC Ceramic is studied through AUTODYN® finite element simulations for normal and oblique (NATO 60°) against long rod projectile (LRP) with a conical tip. The LRP and CP are modeled using smooth particle hydrodynamic (SPH) particles and rest of the component is modeled using Lagrangian domain. The numerical analyses of Armor modules are compared via depth of penetration (DOP) and LRP residual length for varying cover plate thicknesses.
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criterion for interface defeat to penetration transition of long rod projectile impact on Ceramic Armor
Thin-walled Structures, 2017Co-Authors: Xianfeng Zhang, Ahmad Serjouei, I SridharAbstract:Abstract In this paper, an analytical model for the prediction of damage evolution, through impact of long rod projectile (LRP), at interface defeat condition, against silicon carbide (SiC) target is developed. The model comprises four calculation parts, namely interface pressure distribution, stress state in the Ceramic target, wing cracks micro-mechanical and macro-cone crack propagation. A micro-mechanical constitutive model with wing crack distribution is used for inelastic deformation of Ceramic. Subsurface damage evolution in Ceramic impacted by blunt and conical LRPs at different impact velocities and length scales are presented to depict the potential mechanisms involved in transition from interface defeat to penetration. The damage evolution results agree well with the available literature experimental measurements. The proposed possible criteria can be used to predict the interface defeat to penetration transition for blunt and conical LRPs.
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influence of geometry and hardness of the backing plate on ballistic performance of bi layer Ceramic Armor
Procedia Engineering, 2017Co-Authors: Govind Gour, Ahmad Serjouei, I SridharAbstract:Abstract The high hardness and strength of technical Ceramics is exploited to design ballistic Armors and their low toughness, brittleness is overcome by joining them with a metallic or long fiber reinforced composite backing plate. The thickness of backing plate (BP) on the ballistic performance SiC Ceramic Armor is studied through finite element simulations based on AUTODYN®. In this work, depth of penetration (DOP) from experimental measurements is compared with simulations using explicit software AUTODYN® for 3D modelling. The ballistic performance of three layer Armor (cover plate (CP), Ceramic tile and backing plate (BP)) under normal and oblique (NATO 60°) for long rod projectile (LRP) with a conical tip is investigated. The LRP and CP have been modelled using smooth particle hydrodynamic (SPH) particles and rest of the component is modelled using lagrangian processor. The Johnson-Cook and Johnson-Holmquist (JH-2) constitutive models are used for metal and Ceramic materials, respectively. It is found that thicker BP enhances SiC Armor via supporting longer period and prevent any premature failure at the rear surface of Ceramic. It is also noticed that high hardness (low ductile) BP improves the ballistic performance of Ceramic Armor through offsetting tension of Ceramic.
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pre stress effect on confined Ceramic Armor ballistic performance
International Journal of Impact Engineering, 2015Co-Authors: Runqiang Chi, Ahmad Serjouei, I Sridhar, Tan E B GeoffreyAbstract:Abstract A numerical technique for the simulation of pre-stressed confined Ceramic targets under long rod projectile (LRP) impact, using explicit software, AUTODYN®, is proposed. The proposed model is validated by comparing the ballistic performance results with the available experimental data in the literature. Impact simulations of the confined Ceramic targets with different pre-stress conditions, namely radial, axial and hydrostatic, as well as without pre-stress for benchmarking are reported. The effects of these different pre-stress conditions on the ballistic performance of the Ceramic target are explored. The upper limits of transition velocity for the targets of different pre-stress conditions are obtained. It is shown that dwell of the LRP on the Ceramic interface is influenced by the pressure, obtained from pre-stressing, at the initial failure position in SiC target. It is shown that pressure at the initial failure position increases linearly with the upper limit of transition velocity.
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Modelling and analysis of bi-layer Ceramic–metal protective structures
2014Co-Authors: Ahmad SerjoueiAbstract:Technical Ceramics due to their high specific hardness and compressive strength under pressure loading are attractive materials for Armor structures. However, the low toughness of the Ceramics is limiting their usage in practical designs. Adding a strong and tough plate at the back of the Ceramic plate such as metal or polymer composite laminate, is one of the states of the art Armor design that is extensively studied by researchers. Due to the cost of field experiments in defense industry, development of analytical, numerical/empirical models to estimate the ballistic velocity of Armor systems by considering geometry of the projectile and target structure is gaining importance. Optimization of the Armor design for either weight or thickness is also an important criterion. Furthermore, improving the toughness of the Ceramic employing different means like adding metallic phases or pre-stressing them is of considerable interest. In the present thesis, a semi-analytical model is presented for impact of flat-ended (blunt) hard projectiles against Ceramic–metal Armor. Comprehensive numerical simulations are performed based on which it is shown that the projectile residual velocity and BLV satisfy the replica scaling laws. An empirical equation for the BLV is proposed whereby the influence of projectile and Armor geometrical parameters on the BLV is explored. Experimental work is performed for validating the proposed semi-analytical model on alumina–aluminum Armor system. A numerical model is then developed through matching with experimental results based on which variation of the length of the projectile with time and also with front plate and backing plate thicknesses is found. A generalized empirical model to estimate the BLV, as a function of geometrical and material parameters for Ceramic–metal bi-layer Armor systems impacted by a blunt projectile, is proposed. Comparison between results obtained from the empirical model for the BLV of Ceramic–metal Armor impacted by blunt projectiles, with the available experimental data is carried out. The proposed empirical BLV equations and the developed numerical model based on experimental results are employed for optimization of Ceramic–metal Armor systems, under blunt hard projectile impact, for given constraints of total thickness or areal density (mass per unit area) of the Armor. A new analytical model, accounting for erosion and plastic deformation mechanisms, is proposed for the conical projectile impact onto bi-layer Ceramic–metal Armor system, extended based on Recht’s model for the blunt projectile impact onto a monolithic Armor. The residual length of the projectile and the time taken for the erosion and plastic deformation are found. Finally, the effect of different types of pre-stress conditions such as radial, axial and hydrostatic on the penetration response of confined thick SiC Ceramic Armor under tungsten long rod impact is explored through AUTODYN based numerical simulations. It is shown that pressure below and near to the impact site of the confined Ceramic target at the locations where damage initiates is important in the transition behavior from dwell to penetration for targets of various pre-stress states and of different pre-stress ratios.Doctor of Philosophy (MAE
Fábio De Oliveira Braga - One of the best experts on this subject based on the ideXlab platform.
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effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Journal of materials research and technology, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Abstract Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification.
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Effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Elsevier, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification. Keywords: Ballistic test, Ceramic Armor, Multilayered Armor system, Impact geometr
Sergio Neves Monteiro - One of the best experts on this subject based on the ideXlab platform.
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effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Journal of materials research and technology, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Abstract Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification.
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Effect of the impact geometry in the ballistic trauma absorption of a Ceramic multilayered Armor system
Elsevier, 2018Co-Authors: Fábio De Oliveira Braga, Fernanda Santos Da Luz, Sergio Neves Monteiro, Édio Pereira LimaAbstract:Ceramic Armors are frequently used for protection against high energy projectiles, such as the 7.62 mm and 5.56 mm. Recently, it has been demonstrated that a modification in the geometry of the impact face, from flat to convex, enlarges the stress distribution zone created by the projectile-target interaction. This effect raises the projectile's energy absorption and might improve the user's safety. In the present work, the objective is to characterize Ceramic Armor plates with convex impact face, by means of the NIJ-0101.06 (2008) standard methodology, aiming to provide an eventual application in Armor vests. The characterization is based on the measurement of the backface signature, a deformation behind Armor imprinted in a reference material that simulates the consistency of the human body. The results showed significant improvement in the ballistic performance after the impact geometry modification. Keywords: Ballistic test, Ceramic Armor, Multilayered Armor system, Impact geometr
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how effective is a convex al2o3 nb2o5 Ceramic Armor
Ceramics International, 2016Co-Authors: Sergio Neves Monteiro, Luis Henrique Leme Louro, Alaelson Vieira Gomes, Carlos Frederico De Matos Chagas, Aldelio Bueno Caldeira, Édio Pereira LimaAbstract:Abstract Ceramic materials are under increasing attention as a component in ballistic Armor, especially for protection against high impact energy ammunition. In multilayered Armors, a front Ceramic plate can dissipate more than 50% of the impact energy and investigations are continuously trying to increase this performance. This communication revealed, for the first time, how much impact energy is dissipated in an Al2O3–4 wt% Nb2O5 convex-curved surface Ceramic Armor by high velocity 7.62 mm ammunition. Both ballistic simulation and actual tests indicate a 16–18% superior performance of the convex-curved surface as compared to the flat surface Ceramic.
Yangwei Wang - One of the best experts on this subject based on the ideXlab platform.
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effect of glass cover layer on the ballistic performance of transparent Ceramic Armor
Ceramics International, 2021Co-Authors: Zihan Xin, Yangwei Wang, Huanwu Cheng, Xingwang Cheng, Jian ZhangAbstract:Abstract Transparent Ceramics are typically used as the strike-face layer owing to their superior mechanical properties, such as high strength and high hardness. For typical transparent Ceramic Armor, the Ceramic layer is usually divided into small Ceramic tiles because of the size limitations. However, the tiled structure is restricted in application due to the discontinuity between Ceramic tiles, which can be solved by covering the outer surface with a glass plate. In this study, the effect of the glass cover layer on the ballistic performance of transparent Ceramic Armor is investigated through a combination of experimental testing and finite element (FE) simulation. The results exhibited that under the impact of 7.62 mm Armor-piercing incendiaries, the Ceramic tiles were prematurely damaged when the glass cover was added. Besides, the reduction of the Ceramic energy dissipation was greater than the energy dissipation of the glass cover itself, thus reducing the ballistic performance of the transparent Ceramic Armor. The results also revealed that the pre-damage area increased as the thickness of the glass cover increased from 1 mm to 4 mm.
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an analysis of bi layer Ceramic Armor and optimization of protection efficiency
Materials & Design, 2021Co-Authors: Bowen Zhang, Yangwei Wang, Zhikun Yang, Huanwu Cheng, Qunbo FanAbstract:Abstract The bi-layer composite Ceramic Armors are widely used in the protection field, and its design method is keep changing since the Florence model has been found. In this study, an analytical design method of bi-layer was proposed and examined with a new Ceramic protection efficiency definition. With this definition, the protection efficiency of composite Ceramic Armor can be divided into two independent parts: the protection efficiency of Ceramic and the protection efficiency of backing plate. By using this analytical design method, the design of the bi-layer Ceramic Armor can be more efficiency and the material of Armor can be selected more accurately.