3 research outputs found
Bulletproof Vests/shields Prepared From Composite Material Based On Strong Polyamide Fibers And Epoxy Resin
Fiber Reinforced Plastics (FRP) have arisen as a main class of tactual materials having high strength and light weight implemented in a large scale of different applications. This study performs a comparison between the enhanced propidines of Kevlar 49 fiber and Twaron CT 704 reinforced with epoxy resin to obtain an efficient, light weight and slim body m o r capable of resisting high speed projectiles (9 mm bullets). Reinforcing the fabrics adds extra strength to the fabrics instead of using several unreinforced fabrics which increases the weight thickness and the cost of the final product. The response of the prepared composite material based on the two different fibers was studied by using a test barrel for the penetration test. In addition. indentation test is also au lied to compare between the mechanical properties of both laminates and determine which fabric is better for life protection application. The final results showed that using the technique of reinforcing the fabrics specially Twaron is much better where the final bulletproof shield has a smaller number of layers and was found lighter by 40% than those made by Kevlar
Composite Materials Based On Twaron And Nano Materials
This research aims to participate in producing body shield that can overcome pervious drawbacks using behavior of shear thickening fluid. Initially, the rheological behavior of silica-polyethylene glycol shear thickening fluid is examined at different concentrations. Then, ballistic fabric samples are impregnated into silica-polyethylene glycol shear thickening fluid at various concentrations of silica and tested using gas gun simulating real ballistic threat. After that, the impact of rubbery hot water pack filled with around 66.67 wt% starch in water is tested using gas gun. Results showed as the concentration of silica increases, the indentation depth in the impregnated fabric decreases which may result in improving performance of ballistic fabric to 12.5 % in case of using 60 wt% silica, 7.35 % in case of using 30 wt% silica and 3.31 % in case of using 7.5 wt% silica with respect to plain sample. As it showed that no indentation depth is formed in modelling clay when rubbery hot water pack filled with around 66.67 wt% starch in water is tested using gas gun causing improvement percentage to be 100% compared to plain sample of Twaron (CT 714)
Shear Thickening Fluids Comparative Analysis Composed of Silica Nanoparticles in Polyethylene Glycol and Starch in Water
Shear thickening fluid (STF) occurs in dispersions of highly condensed colloid particles and is categorized as a non-Newtonian fluid whose viscosity increases under shear loading which makes them beneficial in protective and impact resistance applications. The aim of this study is to synthesis two different STFs and characterize their microstructural properties to provide a data base for comparing the final macrobehavior of the two fluids under mechanical testing. Therefore, fumed silica and polyethylene glycol STF and starch with water STF-based dispersions were prepared. The particle size, zeta potential, SEM micrographs, and rheological analysis were performed for each type of STF. The effect of filler concentration was observed by using 10–30 weight% filling material. The rheological properties of STFs show higher viscosity measurements at same shear rates for starch/water STF than silica/PEG with maximum viscosity reaching 523.6 Pa s and 178.9 Pa s, respectively. Larger starch particle size over silica recorded as 303.7 nm and 16.49 nm, respectively, and zeta potential analysis recorded particle electrostatic charges as 22.6 mV and 12.8 mV, respectively, leading to more dispersion stability and obvious thickening effect at higher particle concentration leading to greater jump in viscosity at sudden shear rate. The results indicate the capability of trying more protective applications with more flexibility and less thickness when STF is implemented and a good database for the fluids to choose from according to their behavior