An investigation of the effect of a Kevlar-29 composite cover layer on the penetration behavior of a ceramic armor system against 7.62 mm APM2 projectiles

The quasi-static punch shear behaviors of thermoplastic composites with different polymer matrices and fiber types were investigated. This study was also focused on how much energy absorption capability can be increased by low fiber fractions. Maleic anhydride grafted polypropylene (MA-g-PP) and acrylonitrile butadiene styrene (MA-g-ABS) were used as the matrix material. One layer of aramid, carbon and glass fiber plain weave fabrics was used as the reinforcement material. Quasi-static punch shear test (QS-PST) was applied to the samples to understand the penetration behavior of the samples. The damaged areas were investigated and related to force-displacement curves. The results showed that the neat form of MA-g-PP exhibited 158% more energy absorption than the neat form of MA-g-ABS. In the samples containing one layer of fabric, the highest improvement was observed in the aramid fabric-reinforced MA-g-ABS matrix composites. Aramid fabric increased the energy absorption at a rate of 142.3% in comparison to the neat MA-g-ABS, while carbon fiber fabric and glass fiber fabric increased it by 40% and 63.52%, respectively. Aramid fiber fabric provided no significant improvement in the energy absorption in the MA-g-PP matrix composites, while carbon and glass fiber fabrics contributed to energy absorption at a rate of 48% and 41%, respectively.

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Mechanical Properties of Secondary Wall and Compound Corner Middle Lamella near the Phenol-Formaldehyde (PF) Adhesive Bond Line Measured by Nanoindentation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1746 ◽

2011 ◽

Vol 236-238 ◽

pp. 1746-1751 ◽

Cited By ~ 7

Author(s):

Kun Liang ◽

Guan Ben Du ◽

Omid Hosseinaei ◽

Si Qun Wang ◽

Hui Wang

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Secondary Wall ◽

Phenol Formaldehyde ◽

Middle Lamella ◽

Adhesive Bond ◽

Cellular Level ◽

Bond Line ◽

Line Region ◽

Penetration Behavior

To find out the penetration of PF into the wood cell wall and its effects onthe mechanical properties in the cellular level, the elastic modulus and hardness of secondary wall (S2layer) and compound corner middle lamella (CCML) near PF bond line region were determined by nanoindentation. Compare to the reference cell walls (unaffected by PF), PF penetration into the wood tissues showed improved elastic modulus and hardness. And the mechanical properties decreased slowly with the increasing the distance from the bond line, which are attributed to the effects of PF penetration into S2layer and CCML. The reduced elastic modulus variations were from18.8 to 14.4 GPa for S2layer, and from10.1 to 7.65 GPa for CCML. The hardness was from 0.67 to 0.52 GPa for S2layer, and from 0.65 to 0.52 GPa for CCML. In each test viewpoint place, the average hardness of CCML was almost as high as that of S2layer, but the reduced elastic modulus was about 50% less than that of S2layer. But the increase ratio of mechanical properties was close. All the results showed PF penetrates into the CCML. The penetration behavior and penetration depth from bond line were similar in both S2layer and CCML.

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Influence of Rigid Brazilian Natural Fiber Arrangements in Polymer Composites: Energy Absorption and Ballistic Efficiency

Journal of Composites Science ◽

10.3390/jcs5080201 ◽

2021 ◽

Vol 5 (8) ◽

pp. 201

Author(s):

Fabio C. Garcia Filho ◽

Fernanda S. Luz ◽

Michelle S. Oliveira ◽

Wendell B. A. Bezerra ◽

Josiane D. V. Barbosa ◽

...

Keyword(s):

Polymer Composites ◽

Energy Absorption ◽

Natural Fiber ◽

High Energy ◽

Matrix Composites ◽

Lignocellulosic Fibers ◽

Efficiency Performance ◽

Epoxy Matrix Composite ◽

Polymeric Matrix Composites ◽

Armor System

Since the mid-2000s, several studies were carried out regarding the development of ballistic resistant materials based on polymeric matrix composites reinforced with natural lignocellulosic fibers (NLFs). The results reported so far are promising and are often comparable to commonly used materials such as KevlarTM, especially when used as an intermediate layer in a multilayer armor system (MAS). However, the most suitable configuration for these polymer composites reinforced with NLFs when subjected to high strain rates still lacks investigation. This work aimed to evaluate four possible arrangements for epoxy matrix composite reinforced with a stiff Brazilian NLF, piassava fiber, regarding energy absorption, and ballistic efficiency. Performance was evaluated against the ballistic impact of high-energy 7.62 mm ammunition. Obtained results were statistically validated by means of analysis of variance (ANOVA) and Tukey’s honest test. Furthermore, the micromechanics associated with the failure of these composites were determined. Energy absorption of the same magnitude as KevlarTM and indentation depth below the limit predicted by NIJ standard were obtained for all conditions.

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Zero-field MAMMOS recording system with a blue laser, NA=0.95 lens, fast magnetic coil, and thin cover layer

10.1117/12.532410 ◽

2003 ◽

Author(s):

Ferry Zijp ◽

Ruud J. M. Vullers ◽

H. W. van Kesteren ◽

Martin B. van der Mark ◽

C. A. van den Heuvel ◽

...

Keyword(s):

Recording System ◽

Blue Laser ◽

Zero Field ◽

Cover Layer ◽

Magnetic Coil

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Evaluation of Nanoparticle Penetration in the Tumor Spheroid Using Two-Photon Microscopy

Biomedicines ◽

10.3390/biomedicines9010010 ◽

2020 ◽

Vol 9 (1) ◽

pp. 10

Author(s):

Feby Wijaya Pratiwi ◽

Chien-Chung Peng ◽

Si-Han Wu ◽

Chiung Wen Kuo ◽

Chung-Yuan Mou ◽

...

Keyword(s):

Physicochemical Properties ◽

Solid Tumors ◽

Physicochemical Parameters ◽

Mesoporous Silica Nanoparticles ◽

Model System ◽

Tumor Spheroid ◽

Two Photon Microscopy ◽

Two Photon ◽

Tumor Region ◽

Penetration Behavior

Mesoporous silica nanoparticles (MSNs) have emerged as a prominent nanomedicine platform, especially for tumor-related nanocarrier systems. However, there is increasing concern about the ability of nanoparticles (NPs) to penetrate solid tumors, resulting in compromised antitumor efficacy. Because the physicochemical properties of NPs play a significant role in their penetration and accumulation in solid tumors, it is essential to systematically study their relationship in a model system. Here, we report a multihierarchical assessment of the accumulation and penetration of fluorescence-labeled MSNs with nine different physicochemical properties in tumor spheroids using two-photon microscopy. Our results indicated that individual physicochemical parameters separately could not define the MSNs’ ability to accumulate in a deeper tumor region; their features are entangled. We observed that the MSNs’ stability determined their success in reaching the hypoxia region. Moreover, the change in the MSNs’ penetration behavior postprotein crowning was associated with both the original properties of NPs and proteins on their surfaces.

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