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Even though natural fiber reinforced polymer composites (NFRPCs) have been widely used in automotive and building industries, there is still a room to promote them to high-level structural applications such as primary structural component specifically for bullet proof and ballistic applications. The promising performance of Kevlar fabrics and aramid had widely implemented in numerous ballistic and bullet proof applications including for bullet proof helmets, vest, and other armor parts provides an acceptable range of protection to soldiers. However, disposal of used Kevlar products would affect the disruption of the ecosystem and pollutes the environment. Replacing the current Kevlar fabric and aramid in the protective equipment with natural fibers with enhanced kinetic energy absorption and dissipation has been significant effort to upgrade the ballistic performance of the composite structure with green and renewable resources. The vast availability, low cost and ease of manufacturing of natural fibers have grasped the attention of researchers around the globe in order to study them in heavy armory equipment and high durable products. The possibility in enhancement of natural fiber’s mechanical properties has led the extension of research studies toward the application of NFRPCs for structural and ballistic applications. Hence, this article established a state-of-the-art review on the influence of utilizing various natural fibers as an alternative material to Kevlar fabric for armor structure system. The article also focuses on the effect of layering and sequencing of natural fiber fabric in the composites to advance the current armor structure system.

Over the last decade, the progressive application of natural fibres in polymer composites has had a major effect in alleviating environmental impacts. Recently, there is a growing interest in the development of green materials in a woven form by utilising natural fibres from lignocellulosic materials for many applications such as structural, non-structural composites, household utilities, automobile parts, aerospace components, flooring, and ballistic materials. Woven materials are one of the most promising materials for substituting or hybridising with synthetic polymeric materials in the production of natural fibre polymer composites (NFPCs). These woven materials are flexible, able to be tailored to the specific needs and have better mechanical properties due to their weaving structures. Seeing that the potential advantages of woven materials in the fabrication of NFPC, this paper presents a detailed review of studies related to woven materials. A variety of factors that influence the properties of the resultant woven NFRC such as yarn characteristics, fabric properties as well as manufacturing parameters were discussed. Past and current research efforts on the development of woven NFPCs from various polymer matrices including polypropylene, polylactic acid, epoxy and polyester and the properties of the resultant composites were also compiled. Last but not least, the applications, challenges, and prospects in the field also were highlighted.

With the development of technology, bulletproof vests need to have better impact resistance, but the experiment is difficult, costly, and dangerous. Using ANSYS finite element software is an effective alternative. This paper focuses on the impact resistance of composite materials composed of boron carbide ceramics and UHMWPE ultra-high molecular weight polyethylene fibers, respectively, to change the thickness of the two materials to get the effect of the target plate thickness on the performance of the material target plate. Finally, the obtained boron carbide ceramic thickness of 14mm and fiber thickness of 12mm, that is, 24 layers, allowed the material target plate to effectively intercept the bullet, which is in line with expectations.

The review discusses the advancements in the impact resistance properties of bulletproof fiber/ceramic matrix composites. It highlights the critical role of ballistic materials in modern warfare and personal protection, underscoring the necessity for high-performance, lightweight, and flexible options. The analysis systematically investigates three composite systems-carbon fiber/ceramic, silicon carbide/ceramic, and oxide/ceramic matrix composites, focusing on their impact resistance capabilities. Key aspects, including strain-rate-dependent material response optimization, multi-scale damage modes, and performance variations under different impact velocities Lastly, the review outlines the existing challenges and future research directions to advance the utilization of ballistic fiber/ceramic matrix composites in protective applications.

Recent theories predict that discontinuous shear thickening (DST) involves an instability, the nature of which remains elusive. Here, we explore unsteady dynamics in a dense cornstarch suspension by coupling long rheological measurements under constant shear stresses to ultrasound imaging. We demonstrate that unsteadiness in DST results from localized bands that travel along the vorticity direction with a specific signature on the global shear rate response. These propagating events coexist with quiescent phases for stresses slightly above DST onset, resulting in intermittent, turbulentlike dynamics. Deeper into DST, events proliferate, leading to simpler, Gaussian dynamics. We interpret our results in terms of unstable vorticity bands as inferred from recent model and numerical simulations.

Natural-fiber-reinforced polymer composites have recently drawn attention as new materials for ballistic armor due to sustainability benefits and lower cost as compared to conventional synthetic fibers, such as aramid and ultra-high-molecular-weight polyethylene (UHMWPE). In the present work, a comparison was carried out between the ballistic performance of UHMWPE composite, commercially known as Dyneema, and epoxy composite reinforced with 30 vol % natural fibers extracted from pineapple leaves (PALF) in a hard armor system. This hard armor system aims to provide additional protection to conventional level IIIA ballistic armor vests, made with Kevlar, by introducing the PALF composite plate, effectively changing the ballistic armor into level III. This level of protection allows the ballistic armor to be safely subjected to higher impact projectiles, such as 7.62 mm caliber rifle ammunition. The results indicate that a hard armor with a ceramic front followed by the PALF/epoxy composite meets the National Institute of Justice (NIJ) international standard for level III protection and performs comparably to that of the Dyneema plate, commonly used in armor vests.

With higher requirements of ballistic performance put forward by the new generation of armored vehicles, the development of new armored materials at home and abroad has made great progress. In this paper, the development status of composite ballistic armor used in armored vehicles at home and abroad is reviewed, the future development demand of composite ballistic armor used in armored vehicles is summarized, and the application prospect of new materials such as gradient functional materials, micro-laminated materials, graphene modified ceramics in armored vehicles is prospected. In order to meet the independent development needs of armored vehicles in China, it is urgent to develop new advanced lightweight protective materials with excellent performance. Only by developing new armor materials can we improve the survivability of our armored vehicles, meet the operational requirements of our weapons and equipment, and realize the synchronous development with advanced armor protection technology in the world.

Artillery is known as the “God of War”. When the ballistic performance of the barrel is reduced to the allowable value specified by the index due to erosion and wear, the life of the barrel is terminated, and the artillery equipment completely loses its combat effectiveness. The erosion and wear of the barrel involves many factors such as temperature, mechanics, chemistry. In this paper, based on the theory of internal ballistics and heat conduction, the temperature gradient distribution law of the inner wall of the barrel during the firing process of large-caliber artillery is simulated and calculated. Combined with Fick’s second law and the theory of metal phase transition, The relationship between the [C] content in the thermochemically affected layer of the barrel and the number of firing, the relationship between the thickness of the thermally affected layer and the explosion temperature of the propellant and the temperature of the inner wall were quantitatively analyzed. On this basis, the anatomical analysis of different parts of the barrel after firing verified the accuracy of the erosion model, quantitatively revealed the barrel erosion mechanism, and clarified the direction for the life improvement of large-caliber artillery barrels.

The need to provide a better and stronger protection against various kinds of ballistic impacts and threats has necessitated the continuous exploration and utilization of high-performance fibres, especially those that are derived from renewable sources for ballistic applications. The development of ballistic protection materials with improved performance and low weight has received much concerns in the past few decades due to the rising cases of threats and insurgencies. Owing to the necessity of improving the ballistic performance of body armour and protective wears especially for military personnel, with a huge consideration for eco-friendly requirement, a review of relevant studies in this area is necessary. Present review article aims to present an overview of the progress and the outstanding advances that have been witnessed in the development of natural-based anti-ballistic composites in the past few years. The article covers the type and selection of the fibre/matrix, failure modes, Impact energy absorption and ballistic simulation of NFRCs. It also highlights the economic cost analysis of replacing synthetic fibres with natural ones in a ballistic composite, and the methods of enhancing the composites for high performance and greater ballistic efficiency. The utilization of natural fibres in PMCs have shown their great potentials as substitutes to the existing advanced fibrous materials that are mostly dominated by synthetic fibres.

It is well known that silicon carbide (SiC) ceramic is a pressure dependent material, where the compressive strength increases as the pressure increases. So, it is an effective way to improve the ballistic performance of SiC ceramic by introducing prestress on ceramics surface. In this paper, the concept of dynamic prestress on SiC ceramic by energetic materials was proposed. Five key factors, including the time of projectiles contact targets, velocity of the long rod projectiles ( V p ), prestress rising stage time ( T r ), prestress descent stage time ( T d ) and peak pressure of prestress ( P k ), were selected to investigate the effect of dynamic prestress on SiC ceramic targets against long rod impact. The effect of dynamic prestress on the ballistic performance of SiC ceramic were investigated, and the dynamic prestress path which can increase the protection capability of SiC ceramic was given. The results indicated that, in most cases, the ballistic performance of the dynamic prestressed SiC ceramic targets against long rod projectiles impact was improved. However, it was also revealed that not all dynamic prestressing can improve the ballistic performance of SiC ceramic targets. It will be benefit to the ballistic performance of SiC ceramic by controlling the prestress time to make sure the moment of the long rod projectile impacts the target in between T 2 and T 4 . The sequence of influence degree of each factor on the erosion length of long rod projectile is the velocity of long rod projectiles ( V p ), prestress descent stage time ( T d ), peak pressure of prestress ( P k ) and prestress rising stage time ( T r ). The erosion length of long rod projectile decreases with the increase of V p , and increases with the increase of prestress descent stage time ( T d ), peak pressure of prestress ( P k ) and prestress rising stage time ( T r ).