High Velocity Impact Characteristics of Shear Thickening Fluid Impregnated Kevlar Fabric

This investigation aims to study the efficiency of STF impregnated plain-weave fabric made of Kevlar under high and low velocity impact conditions. The shear thickening fluid (STF) was prepared by ultrasound irradiation of silica nanoparticles (diameter ≈30 nm) dispersed in liquid polyethylene glycol polymer. STF impregnation effect was determined from single yarn pull-out test and penetration at low velocity using drop weight machine equipped with hemi-spherical penetrator and dynamic force sensor. Force-displacement curves of neat and impregnated Kevlar were analysed and compared. Also, the STF impregnation effect on Kevlar multilayers was analysed from high velocity impact tests using 9mm FMJ bullet at 390 m/s. After impact, Back face deformation (BFD) of neat and impregnated Kevlar layers were measured and compared. Results showed that STF impregnated fabrics have better energy absorption and penetration resistance as compared to neat fabrics without affecting the fabric flexibility. When relative yarn translations are restricted (e.g. at very high levels of friction), windowing and yarn pull-out cannot occur, and the fibres engaged with the projectile fail in tension that leads to fabric penetration. Microscopy of these fabrics after testing have shown pitting and damage to the Kevlar filaments caused by the hard silica particles used in the STF. Mesoscopic 3D Finite Element models were developed using explicit LS-DYNA hydrocode to account for STF impregnation by employing the experimental results of yarn pull-out tests, low and high velocity impacts. It was found that friction between fibers and yarns increase the dissipation of energy upon impact by restricting fiber mobility, increasing the energy required for relative yarn translations and transferring the impact energy to a larger number of fibers.

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High velocity impact characteristics of MWNT added CFRP at LEO space environment

Advanced Composite Materials ◽

10.1080/09243046.2017.1327183 ◽

2017 ◽

Vol 26 (5) ◽

pp. 391-406 ◽

Cited By ~ 2

Author(s):

Jin-Bum Moon ◽

Hong-Kyu Jang ◽

Chun-Gon Kim

Keyword(s):

High Velocity ◽

Space Environment ◽

High Velocity Impact ◽

Velocity Impact ◽

Impact Characteristics

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Experimental and numerical analysis of penetration into Kevlar fabric impregnated with shear thickening fluid

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717704485 ◽

2017 ◽

Vol 31 (3) ◽

pp. 392-407 ◽

Cited By ~ 19

Author(s):

A Khodadadi ◽

GH Liaghat ◽

AR Sabet ◽

H Hadavinia ◽

A Aboutorabi ◽

...

Keyword(s):

High Velocity ◽

Shear Thickening ◽

Element Model ◽

High Velocity Impact ◽

Ballistic Performance ◽

Velocity Impact ◽

Impact Performance ◽

Pull Out ◽

Shear Thickening Fluids

This study presents the high-velocity impact performance of a composite material composed of woven Kevlar fabric impregnated with a colloidal shear thickening fluids (STFs). Although the precise role of the STF in the high-velocity defeat, process is not exactly known but it is suspected to be due to the increased frictional interaction between yarns in impregnated fabrics. In order to explore the mechanism of this enhanced energy absorption, high-velocity impact test was conducted on neat, impregnated fabric and also on pure STF without fabric. A finite element model has been carried out to consider the effect of STF impregnation on the ballistic performance. For this purpose, fabric was modeled using LS-DYNA by employing the experimental results of yarn pull-out tests to characterize the frictional behavior of the STF impregnated fabric. The simulation result is a proof that the increased performance for STF impregnated Kevlar fabric is due to the increased friction.

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High-Velocity Impact on Composite Sandwich Structures: A Theoretical Model

International Journal of Mechanical Sciences ◽

10.1016/j.ijmecsci.2021.106459 ◽

2021 ◽

pp. 106459

Author(s):

L. Alonso ◽

A. Solis

Keyword(s):

Theoretical Model ◽

High Velocity ◽

Sandwich Structures ◽

High Velocity Impact ◽

Velocity Impact ◽

Composite Sandwich ◽

Composite Sandwich Structures

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Effect of strain rate, off-axis loading and high-velocity impact damage on the compressive strength of C/SiC composite

Journal of Composite Materials ◽

10.1177/0021998318787618 ◽

2018 ◽

Vol 53 (4) ◽

pp. 535-546 ◽

Cited By ~ 1

Author(s):

M Altaf ◽

S Singh ◽

VV Bhanu Prasad ◽

Manish Patel

Keyword(s):

Compressive Strength ◽

Strain Rate ◽

High Velocity ◽

Impact Damage ◽

The Other ◽

High Velocity Impact ◽

Fibre Bundles ◽

Velocity Impact ◽

Kink Bands ◽

Other Hand

The compressive strength of C/SiC composite at different strain rates, off-axis orientations and after high-velocity impact was studied. The compressive strength was found to be 137 ± 23, 130 ± 46 and 162 ± 33 MPa at a strain rate of 3.3 × 10−5, 3.3 × 10−3, 3.3 × 10−3 s−1, respectively. On the other hand, the compressive strength was found to be 130 ± 46, 99 ± 23 and 87 ± 9 MPa for 0°/90°, 30°/60° and 45°/45° fibre orientations to loading direction, respectively. After high-velocity impact, the residual compressive strength of C/SiC composite was found to be 58 ± 26, 44 ± 18 and 36 ± 3.5 MPa after impact with 100, 150 and 190 m/s, respectively. The formation of kink bands in fibre bundles was found to be dominant micro-mechanism for compressive failure of C/SiC composite for 0°/90° orientation. On the other hand, delamination and the fibre bundles rotation were found to be the dominant mechanism for off-axis failure of composite.

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