Ceramic Materials for Ballistic Protection

2009 ◽  
Vol 409 ◽  
pp. 291-294 ◽  
Author(s):  
Richard Klement ◽  
Jan Krestan ◽  
Stanislav Rolc

The ballistic performance of ceramic materials was investigated. Various types of ceramic-metals and ceramic-laminate composites were prepared. Their ballistic resistances against AP small arms ammunition of protection level 2 and 3 according to NATO Standardization Agreement STANAG 4569 were investigated. For the ballistic performance assessment V50 test method was used. From economical, technological, and ballistic point of view as optimal solution sandwich structure consisting of alumina front-face layer and aramid or duralumin backing layer was found.

2014 ◽  
Vol 608 ◽  
pp. 253-258 ◽  
Author(s):  
Priawthida Jantharat ◽  
Ryan C. McCuiston ◽  
Chaiwut Gamonpilas ◽  
Sujarinee Kochawattana

The ballistic performance of transparent armors has been continuously developed for an application on security purposes. Generally, ballistic performance of the laminated glass increases with its thickness and weight while the user requirement prefers high level of ballistic protection with thin and light weight body. In this study, fabrication of light weight glass-PVB transparent armors with the level-3 protection according to the National Institute of Justice (NIJ) standard was attempted. The ballistic performances of various configurations of glass-PVB laminates were determined against 7.62 mm ammunitions. Results from fragmentation analysis indicated the influence of glass-sheet-arrangement in the armor structures on the ballistic damages. The minimum requirement on the thickness of front-face layer was also discussed. To verify the experimental results, finite element analysis was performed on all laminated systems. It was found that the results from computational analysis were in reasonable agreement with the experimental results.


Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1043
Author(s):  
Vitor Bonamigo Moreira ◽  
Anna Puiggalí-Jou ◽  
Emilio Jiménez-Piqué ◽  
Carlos Alemán ◽  
Alvaro Meneguzzi ◽  
...  

Herein, the influence of the substrate in the formation of zirconium oxide monolayer, from an aqueous hexafluorozirconic acid solution, by chemical conversion and by electro-assisted deposition, has been approached. The nanoscale dimensions of the ZrO2 film is affected by the substrate nature and roughness. This study evidenced that the mechanism of Zr-EAD is dependent on the potential applied and on the substrate composition, whereas conversion coating is uniquely dependent on the adsorption reaction time. The zirconium oxide based nanofilms were more homogenous in AA2024 substrates if compared to pure Al grade (AA1100). It was justified by the high content of Cu alloying element present in the grain boundaries of the latter. Such intermetallic active sites favor the obtaining of ZrO2 films, as demonstrated by XPS and AFM results. From a mechanistic point of view, the electrochemical reactions take place simultaneously with the conventional chemical conversion process driven by ions diffusion. Such findings will bring new perspectives for the generation of controlled oxide coatings in modified electrodes used, as for example, in the construction of battery cells; in automotive and in aerospace industries, to replace micrometric layers of zinc phosphate by light-weight zirconium oxide nanometric ones. This study is particularly addressed for the reduction of industrial waste by applying green bath solutions without the need of auxiliary compounds and using lightweight ceramic materials.


Author(s):  
Hasan Kasım

This study aims to determine the ballistic performances of laminated composite plates produced with AA5083-H112 series aluminum and rubber material with high elongation capacity under impact loading. To investigate the effect of rubber compounds, two types of rubber with calendered and damping were prepared. Thanks to the surface treatment applied to the aluminum plates, the rubber–metal adhesion strength was adjusted, and four different laminated composite plate samples were prepared. Calendered rubber was used on the bullet impact surface of all samples, and damping rubber was used on the back. It has been observed that the pressure barrier created by the calendered rubber bullet on the front face provides high performance to absorb energy. A detailed study was carried out on the total thickness of laminated composite plates, the interface adhesion strength between rubber and aluminum layers, and the ballistic performance of aluminum-rubber combinations. It was concluded that the laminated composite plate’s energy absorption would increase, especially by increasing the thickness of the dumping rubber layer on the back of the aluminum sheets. In the strong metal-rubber interface interaction between the rubber and aluminum layer, the bullet is stopped before the pressure barrier is formed. The penetration depth and bulging height increase, and most of the energy are transmitted through the aluminum plate. In the weak metal-rubber interface interaction, a significant portion of the energy is absorbed by the rubber and air thanks to the pressure barrier.


Author(s):  
Kwon Joong Son ◽  
Eric P. Fahrenthold

Magnetorheological (MR) fluids, well established as components of a variety of suspension systems, may offer opportunities to improve the performance of fabric ballistic protection systems, which typically do not incorporate significant energy dissipation mechanisms. A series of ballistic impact experiments has been conducted to investigate the potential of MR fluid damped fabric suspension systems to improve upon current fabric barrier designs. The results indicate that for the simple fabric suspension systems tested, MR fluid damping does not improve upon the very high weight specific ballistic performance of state of the art aramid fibers.


2016 ◽  
Vol 30 (4) ◽  
pp. 545-563 ◽  
Author(s):  
H Shanazari ◽  
GH Liaghat ◽  
H Hadavinia ◽  
A Aboutorabi

In addition to fiber properties, the fabric structure plays an important role in determining ballistic performance of composite body armor textile. Textile structures used in ballistic protection are woven fabrics, unidirectional (UD) fabric structures, and nonwoven fabrics. In this article, an analytical model based on wave propagation and energy balance between the projectile and the target is developed to analyze hybrid fabric panels for ballistic protection. The hybrid panel consists of two types of structure: woven fabrics as the front layers and UD material as the rear layers. The model considers different cross sections of surface of the target in the woven and UD fabric of the hybrid panel. Also the model takes into account possible shear failure by using shear strength together with maximum tensile strain as the failure criteria. Reflections of deformation waves at interface between the layers and also the crimp of the yarn are modeled in the woven part of the hybrid panel. The results show greater efficiency of woven fibers in front layers (more shear resistance) and UD yarns in the rear layers (more tensile resistance), leading to better ballistic performance. Also modeling the yarn crimp results in more trauma at the backface of the panel producing data closer to the experimental results. It was found that there is an optimum ratio of woven to UD materials in the hybrid ballistic panel.


2019 ◽  
Vol 16 (33) ◽  
pp. 823-840
Author(s):  
M. K. TARABAI ◽  
S. G. de AZEVEDO

This paper discusses a possible solution regarding the final disposal of sludge from Sanitary Sewage Treatment Stations (ET), aiming at environmental preservation. The solid waste generated after the wastewater treatment processes is highly contaminating and detrimental to the area in which it is deposited. Given this, the use of sludge with the application of reuse techniques becomes pertinent, both from the economic point of view and from the ecological point of view. By replacing the use of aggregates from mineral deposits, the main clay raw material in the manufacture of ceramic products (Vieira, 2000), by the treated sludge of WWTP we will save on the sources of granular materials. Aiming its reintegration to the production cycle through the introduction of sludge as raw material incorporated in the ceramic mass in the manufacture of hollow bricks, the viability of use was verified through performance analysis, compared to the control brick made of pottery, without the addition of sludge. Specimens were prepared with three types of samples: 90% clay and 10% sludge; 80% clay and 20% sludge; 70% clay and 30% sludge. Mass loss, water absorption index and compressive strength tests were performed. As for the tests, the specimens with 10% and 20% of sludge were the ones that had better adaptation to the technical requirements, but because it is a larger volume of the residue for the application of reuse techniques, the brick with 20% sludge dosage. is the most suitable. NBR7.171, November 1992: Ceramic Block for masonry; Specification NBR 6.461, June 1983: Masonry Ceramic Block - Compressive Strength Check: Test Method; NBR 8.947, November 1992: Ceramic Tile- Determination of Mass and Water Absorption: Test Method. As for the tests, the specimen with 20% of sludge was the one that had the best adaptation to technical and environmental requirements. The present article approaches a possible solution regarding the destination of the sludge coming from Sanitary Sewage Treatment Stations, aiming at environmental preservation. Aiming at its reintegration into the productive cycle through applications of reuse techniques, the sludge became raw material when the ceramic mass was incorporated into the brick fabrication. Three types of samples were elaborated: 90% of clay and 10% of mud; 80% clay and 20% sludge; 70% clay and 30% sludge. As for the tests, the test specimen with 20% of sludge was the one that had more adequacy to the technical and environmental requirements.


2017 ◽  
Vol 6 (1) ◽  
pp. 40
Author(s):  
Zaid Yaseen Saud Al-Dulaimi

Abstract. The aim of this study is to help us to know the degree of Organizational Justice practiced by the administrative leaders in Baghdad for Economic Sciences and of Al-Ma'mun privet university colleges in Baghdad and its relationship to the employees' work or Career Performance. In order to achieve this goal, the study will seek to answer the following questions:What is the degree of Organizational Justice practiced by the administrative leaders in the discussed colleges from the employees' point of view?What is level of work or Career Performance of employees from the point of view of their leaders?The study's society is formed from administrative leaders, heads of departments and discussed faculties. Researchers will use a questionnaire for data collection and it will include, the responder's demographic information, the measuring tool for the Organizational Justice practiced by the administrative leaders, the measurement of Career Performance of their employees. Study Tools has been verified by bringing it to the attention of the arbitrators of jurisdiction, and verification of the appropriateness of using the test method and the test. For answering the questions of the study researchers will use arithmetic averages, standard deviations and Pearson Linklabs.


Author(s):  
O.N. Bekirova ◽  
◽  
S.A. Barkalov ◽  
M.S. Trifonova

The COVID-19 pandemic has really become a real shock for the whole world. The way of life has changed not only for people, but also for companies in various industries. Today, the real estate market, like many other industries, is in conditions of economic instability. The study highlights the problems faced by the construction sector in the current conditions of the coronavirus pandem-ic. One of these problems is the sustainable competitiveness of construction and its compliance with new consumer preferences. Aim. The study of the influence of engineering solutions and other fac-tors on the competitiveness of construction in modern economic conditions, the definition of key criteria. Development and description of the decision-making methodology for choosing the optimal construction enterprise from the point of view of competitiveness. Materials and methods. The methods of system analysis, optimization methods, hierarchy analysis and decision theory are ap-plied in the work. Within the framework of the proposed methodology, the author's method of identifying key competitiveness criteria has been developed. Since the problem of choosing the optimal solution from among the alternatives is based on a multi-criteria approach, the use of this method is quite appropriate. The template for the formation of the methodology was identified based on the analy-sis of existing research in this area. Results. The author summarizes and supplements the criteria and factors affecting the competitiveness of construction organizations in the study. The author's method of making a decision on determining the optimal construction enterprise from the point of view of competitiveness based on the criteria considered by the author is presented. This technique includes several stages: 1) forming a goal; 2) formation of criteria by which organizations will be evaluated; 3) calculation of criteria for each organization and bringing them to a homogeneous type of data; 4) building a tree of goals and a matrix of priorities; 5) Determining the values of priority vectors for each organization under study. Conclusion. The total influence of criteria and engineering solutions on the competitiveness of construction is determined. In this regard, the implementation of the con-struction project should be carried out taking into account the strategic goals of the organization and binding to the identified criteria. The proposed methodology is developed for Russian construc-tion companies operating in modern economic conditions.


Author(s):  
Zhixun Yang ◽  
Jun Yan ◽  
Guojun Ma ◽  
Qingzhen Lu ◽  
Minggang Tang ◽  
...  

Umbilical which links the top floater and the subsea devices provides control functions through electrical cables and hydraulic remote transmission. They are treated as the “lifeline” of the subsea production system for offshore oil and gas exploitation. During operation, umbilical needs to undertake self-weight and periodical load due to the ocean environment. Meanwhile, the heat during power transmission in electric cable is released to the umbilical body, which influences the mechanical properties and optical transmission in the cable. However, there are a number of components and many kinds of sectional arrangement for the umbilical. So the sectional design with multiple components needs to be solved as a multidisciplinary optimization problem. From the mechanical point of view, the umbilical structure should be designed with more compacted and symmetric layout to obtain even probability of resistance to loads and reduce structural stress to improve its fatigue performance. Concerning thermal effect, these units should be arranged to dissipate the heat easily to avoid the influence on the functional and structural components. In this paper, compactedness, symmetry and temperature distribution are quantified through introducing corresponding indices. Then multidisciplinary optimization framework is established. Particle Swarm Optimization (PSO) intelligent algorithm is adopted to carry out the optimization to obtain the optimal solution, which is far superior to the initial design. The optimization design strategy is proved to be effective and efficient by some numerical examples, which provides reference for design of umbilical cables.


Author(s):  
Hasan Kasım

In this study, the ballistic behavior of protective armor plates (PaP) obtained by curing between high structural strength AA7075-T651 aluminum plates by reinforcing with glass balls of two different rubber mixtures whose damping properties were developed with carbon nanotube and glass bubbles fillers were investigated. A total of six PaPs at 27, 30, and 35 mm heights were prepared using two different matrix damping rubbers. High-strength liner rubber used in air bellows is vulcanized on the front and back surfaces of PaPs. Between the PaPs, Ø15.875 and Ø6.747 mm, borosilicate glass balls were placed in a particular arrangement that coincides with the middle of the matrix rubber and does not have any gaps. Liner rubber cured on the front face has managed to hold the energy by forming a layer like clothing around the bullet cores. Glass balls between PAPs play an essential role in the energy absorption of GB-filled mixtures. In contrast, in MWCNT-filled mixtures, they act as a second damping element. The ballistic performance of PAPs prepared with multiwalled carbon nanotubes was determined to be better than those prepared with Glass Bubbles. Thanks to the superior mechanical properties and high aspect ratio of MWCNTs, the penetration and swelling heights of the matrix damping rubbers prepared to have excellent results compared to glass bubbles. With the increase in the thickness of the PaPs prepared with MWCNTs, the deformation effect of the penetration depth and bulging height created by the bullet on the anterior and posterior surfaces decreased. As the thickness of PaP increased from 27 mm to 35 mm, penetration depth decreased by 38%, and bulging height reduced by 35%. The amount of penetration and swelling increased in PaPs using rubber filled with glass bubbles. As the plate thickness increased, the damping feature decreased and the glass balls were activated, and the bullet was stopped.


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