Parametric optimisation of shear thickening fluid treatment for ultra-high molecular weight polyethylene woven fabric

Abstract

The shear thickening fluid (STF) treatment enhances the low and high velocity impact resistance performances of para-aramid woven fabrics for soft armour application. This research investigates the effects of important parameters on the STF add on and impact energy absorption with the aim to develop a hybrid soft armour. The STF add-on on ultra-high molecular weight polyethylene (UHMWPE) woven fabrics was varied by altering the silica particle size, dilution ratio of STF and padding pressure. The results of the full factorial design of experiment showed that the energy absorption is independent of the add-on. Further, a soft armour panel (SAP) was made from the STF treated woven fabric. The ballistic performance of the panel was evaluated in terms of back face signature (BFS) against a 9 × 19 mm lead core bullet and was compared to that of a weight equivalent untreated panel. A hybrid SAP with unidirectional (UD) laminates of UHMWPE as strike face layers and STF treated woven fabrics as backing layers was prepared, and the BFS was found to be equivalent to that of a SAP containing 100% UD laminates (∼30 mm). The results imply that a certain number of UD laminate layers can be replaced with STF treated flexible woven fabrics without compromising on the ballistic performance of SAP.

Synthesis and characterization of monodispersed silica‐based shear thickening fluid for impact resistance applications

“…Moreover, STF dilution with ethanol improves the wettability of the Kevlar fabrics with STFs by reducing the viscosity as well as the surface tension of the STF. To avoid agglomeration and guarantee uniform silica nanoparticle dispersion in the diluted suspension, a high‐speed homogenizer was used 31 . Prior to treatment, the mixture was completely homogenized for 20 min at 21,000 rpm in a homogenizer 28 .…”

“…To avoid agglomeration and guarantee uniform silica nanoparticle dispersion in the diluted suspension, a high-speed homogenizer was used. 31 Prior to treatment, the mixture was completely homogenized for 20 min at 21,000 rpm in a homogenizer. 28 The diluted STF solution was applied to the woven materials on a Mathis Lab Padder padding mangle as the padding rollers crushed them at 2 bar and 3 m min À1 pressure as shown in Figure 1C.…”

“…In our study, we used synthesized monodispersed silica nanoparticles with a diameter of 300 nm, based on Mukesh et al's findings showing their superior peak viscosity compared to 100 and 500 nm particles. 31 The monodispersed nanoparticles were preferred for their uniformity, ensuring consistent shear-thickening response and fluid stability. This choice aims to optimize energy absorption, crucial for body armor against high-velocity impacts.…”

Orthotropic vs quasi-isotropic: How the tape orientation influence the performance of disentangled polyethylene laminates

“…Lightweight soft body armour made from para-aramid [1][2][3][4] and ultrahigh molecular weight polyethylene (UHMWPE) [5][6][7][8] fibres are being used as an advanced system for ballistic protection. Ultrahigh molecular weight polyethylene fibres are gel spun as their melt viscosity is very high whereas para-aramid fibres are manufactured through solution spinning route.…”