Shear thickening fluids using silica-halloysite nanotubes to improve the impact resistance of p-aramid fabrics

2016 ◽  
Vol 132-133 ◽  
pp. 468-474 ◽  
Author(s):  
Animesh Laha ◽  
Abhijit Majumdar
RSC Advances ◽  
2017 ◽  
Vol 7 (78) ◽  
pp. 49787-49794 ◽  
Author(s):  
K. Talreja ◽  
I. Chauhan ◽  
A. Ghosh ◽  
A. Majumdar ◽  
B. S. Butola

Kevlar fabrics treated with MTMS modified silica based STF showed better impact energy absorption as compared to APTES modified and control silica based STF treated fabrics, attributed to changes in interactions between fabrics and silica particles.


2021 ◽  
Vol 10 (2) ◽  
Author(s):  
Aaditya Saha ◽  
Fred Avett

Millions of sports and recreation-related injuries occur each year. Different shock-absorbing solutions, such as polyethylene and polyurethane foams, are used in helmets and protective equipment, but one area most sports-gear manufacturers have not explored is the usage of shear thickening fluids (STFs). An STF is a material that is soft under normal conditions but acts rigid when stressed or pressured. STF composites were fabricated and tested with the goal of exploring their viability for use in shock-absorption applications, especially for sports. The role of fabric- and particle-type, particle-to-carrier fluid ratios, nano-particle additives, and the thickness of the composite were studied, and were all hypothesized to have an effect on the impact-resistance of the fabricated STF-composites. Drop-tests were conducted by releasing a 1.1-lb. weight from an electromagnet onto the composites. An impact-force sensor was placed underneath. The weight and height of the drop were chosen to simulate the hardest recorded NFL hit. All hypothesized factors were found to affect impact resistance. The combination of nylon-fabric impregnated by an STF mix of propylene-glycol and silica-nanoparticles, with a cerium-oxide nano-particle additive, displayed better shock-absorption behavior than other fabricated composites. All of the STF-composites also outperformed tested commercial shock-absorption materials despite being thinner and more flexible. These results demonstrate the potential of using STF-impregnated textile fabrics for protective composites for sportswear, as well as for non-sport shock-absorption applications, like in military vests and helmets, and aerospace applications. Further research is necessary to work towards a final product which can be used.


2016 ◽  
Vol 87 (18) ◽  
pp. 2275-2304 ◽  
Author(s):  
Kadir Bilisik

In this study, the impact resistance of two-dimensional (2D) fabrics and three-dimensional (3D) preforms is explained. These fabrics and preforms include 2D and 3D woven and knitted flat and circular fabrics. Various types of soft/layered structures as well as rigid composite are outlined with some design examples for ballistic and stab threats. The recent developments in nanotubes/nanofibers and shear-thickening fluids (STF) for ballistic fabrics are reviewed. The ballistic properties of single- and multi-layered fabrics are discussed. Their impact mechanism is explained for both soft vest and rigid armor applications. Analytical modeling and computational techniques for the estimation of ballistic properties are outlined. It is concluded that the ballistic/stab properties of fiber-reinforced soft and rigid composites can be enhanced by using high-strength fibers and tough matrices as well as specialized nanomaterials. Ballistic/stab resistance properties were also improved by the development of special fabric architectures. All these design factors are of primary importance for achieving flexible and lightweight ballistic structures with a high ballistic limit.


2016 ◽  
Vol 17 (2) ◽  
pp. 199-204 ◽  
Author(s):  
Abhijit Majumdar ◽  
Bhupendra S. Butola ◽  
Ankita Srivastava ◽  
Debarati Bhattacharjee ◽  
Ipsita Biswas ◽  
...  

2019 ◽  
Vol 11 (3) ◽  
pp. 340-378 ◽  
Author(s):  
Dakshitha Weerasinghe ◽  
Damith Mohotti ◽  
Jeremy Anderson

Soft armour consisting of multi-layered high-performance fabrics are a popular choice for personal protection. Extensive work done in the last few decades suggests that shear thickening fluids improve the impact resistance of woven fabrics. Shear thickening fluid–impregnated fabrics have been proven as an ideal candidate for producing comfortable, high-performance soft body armour. However, the mechanism of defeating a projectile using a shear thickening fluid–impregnated multi-layered fabric is not fully understood and can be considered as a gap in the research done on the improvement of soft armour. Even though considerable progress has been achieved on dry fabrics, limited studies have been performed on shear thickening fluid–impregnated fabrics. The knowledge of simulation of multi-layered fabric armour is not well developed. The complexity in creating the geometry of the yarns, incorporating friction between yarns and initial pre-tension between yarns due to weaving patterns make the numerical modelling a complex process. In addition, the existing knowledge in this area is widely dispersed in the published literature and requires synthesis to enhance the development of shear thickening fluid–impregnated fabrics. Therefore, this article aims to provide a comprehensive review of the current methods of modelling shear thickening fluid–impregnated fabrics with a critical analysis of the techniques used. The review is preceded by an overview of shear thickening behaviour and related mechanisms, followed by a discussion of innovative approaches in numerical modelling of fabrics. A novel state-of-the-art means of modelling shear thickening fluid–impregnated fabrics is proposed in conclusion of the review of current methods. A short case study is also presented using the proposed approach of modelling.


2018 ◽  
Vol 53 (8) ◽  
pp. 1111-1122 ◽  
Author(s):  
Selim Gürgen

Shear thickening fluids have been extensively utilized in composite laminate structures to enhance the impact resistance in the last decade. Despite the contribution of shear thickening fluids to the protective systems, the mechanism behind the energy absorption behavior of shear thickening fluids is not fully understood. In the present study, various configurations of composite laminates were prepared and these structures were investigated under low velocity stab conditions. Contrary to the common idea of shear thickening fluid impregnation for fabrics, shear thickening fluids were used in bulk form and by means of this, pure contribution of shear thickening behavior to the energy absorption was investigated. To hold the bulk shear thickening fluids in the composite laminates, Lantor Soric SF honeycomb layers were filled with shear thickening fluids and Twaron fabrics were plied in the structures as the reinforcement. As a result of this study, it is stated that shear thickening behavior is insufficient to effectively improve the energy absorption performance of composite laminates; however, shear thickening fluids are beneficial to fabric based composites because the inter-yarn friction of fabrics is enhanced using shear thickening fluids as an impregnation agent rather than a bulk form.


2020 ◽  
Vol 54 (24) ◽  
pp. 3515-3526
Author(s):  
Thiago F Santos ◽  
Caroliny M Santos ◽  
Rubens T Fonseca ◽  
Kátia M Melo ◽  
Marcos S Aquino ◽  
...  

Use of colloidal silica suspensions impregnated in Kevlar® fabrics is new avant-garde of protection equipment for stab wounds and piercing objects. Kevlar® fabrics impregnated with non-Newtonian fluids have been used for protection against sharp blows, mainly due to their lightweight, good flexibility, and superior resistance properties. The aims of this investigation are to demonstrate that Kevlar® fabric impregnated with shear thickening fluids could be improved its performance through the use Aminopropyltrimethoxysilane, as well as by increasing the concentration of silica nanoparticles in its composition. Friction tests on yarns showed that Kevlar® yarns with shear thickening fluids (sample C3—25% Silica and 75%polyethylene glycol with 38% aminopropyltrimethoxysilane), presented higher strength values (10.5 N) when compared with other samples. Impact resistance tests showed that Kevlar® samples with highest concentration shear thickening fluids nanoparticles and oriented fabric layers (C3 OR) presented better performance regarding to penetration depth of stabs P1 (17 mm), S1 (18 mm) and as well as residual energy dissipation, when compared with the standard and other samples. Addition of shear thickening fluids cause reduction in the flexibility of the Kevlar® fabrics, producing sample with 42.74% less flexibility than the standard sample (C3). Adhesion tests for C3 samples exhibited more stable wettability and spreading rate, i.e., a greater adhesion of shear thickening fluids in Kevlar® fabrics than other samples due to its composition (higher concentration of nanoparticles and superior amount of silane agent). Finally, results showed that the shear thickening fluids composition as well as Kevlar® layers orientation should be used to improve the performance of Kevlar® fabrics under impact tests.


Sign in / Sign up

Export Citation Format

Share Document