Abstract:

In order to explore the stab-resistant mechanism of high-strength fabrics, the fabric stressing changes and cutter energy transformation occured in the cutters’  stab  process are analysed from the view of mechanics，the stab experiment results of ultra-high molecule weight polyethylene stab-resistant fabric under the static and the dynamic environment verify the theoretical analysis of instantaneous impact force resulting from the cutting tool and the conversion of kinetic energy. The calculation results demonstrate that the instantancous impulse force of the cutter end to the fabric can reach 1811.85 N and the instantaneous pressure can be  7.49×108 Pa under conditions of the stab kinetic energy of 24 J and the stab angle of 0°; and the two are main factors causing the fabric damage. Some kinetic energy produced in the cutter stab process overcomes the fabric elasticity, and the other kinetic energy transforms into heat energy, which allows the fabric to be heated up to at least 100℃, but the specific conversion requires further study. Different  cutter shapes cause different damage mechanisms to fabrics, and have direct impact on the shape and the stab depth, and under the same conditions, the double-edged cutter has the largest stab depth, followed by single-edged cutters and cones.

Key words: stab-resistance mechanism, stab resistance, ultrahigh molecular mass polyethylene, stab experiment, mechanical nanlysis, cutter shape