الفهرس 
INTRODUCTION AND AIM OF THE WORKOnly 14 pages are availabe for public view
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Abstract
In the last decades, the attention in the textile sector has been focused on the designing of protective soft fabrics against stabbing or slashing. Textile products should shield the wearer body from threats caused by pointed or sharp-edged objects such as knives, sharp blades, or spikes. The challenge facing protective fabrics, subjected to slashing or stabbing forces and the problems of composite machining, necessitates an accurate measurement of the cutting force of the fabric under simulated working conditions. In this work, a new design for an apparatus for measuring the cutting force for yams and fabrics was introduced. The cut resistance of the high-performance filament yarns under tension-shear loading conditions was measured using a newly developed rotating set up. The analysis of the mechanism of cutting by the designed apparatus was given. In this study, different materials were used such as yarns from high performance fibers (Kevlar 29, vectran, Kevlar 129, glass, carbon, and polyester). Also, fabrics with different structures (plain weave and triaxial type) were investigated. The results obtained showed that the specific cutting force value of the Kevlar fibers was the highest (7.5cN/tex) compared to carbon (0.24cN/tex) and glass (0.5 lcN/tex) fibers. Polyester filament yarns gave the lowest values. The results showed that the specific cut energy is inversely proportional to the fibers Young’s modulus. The cutting force of the filament yarn is affected significantly by the normal load (for Kevlar decrease of the cutting force is affected highly by the cutting velocity. For an increase in cutting velocity by 50%, the reduction in specific cutting force reached (88%), while in the case of the organic fibers (Kevlar29) the reduction reached (70.3%). Equations relating the cutting resistance with the cutting speed, the normal force and the Young modulus were developed. For fabrics produced from High Performance Yarns (HPY), the type of yarn and the design of the fabric had a significant effect on its cutting resistance.