Investigation of the Spike Penetration Resistance of the Weft-Knitted Fabrics with Different Elasticity Ratio

In this study, the penetration process of three kinds of spikes with different geometries has been investigated while penetrating in rib-knitted fabrics with different proportions of elastic yarn existence. Besides, the tensile behaviour of the fabrics including the breaking force, breaking elongation, work of rupture and tensile modulus of the samples have been measured and their relation to the resistance of the samples against the penetration performance of spikes were analysed. In this regard, the force, depth, and energy required for penetration have been estimated. In addition, the images of the damages caused by the penetration of spikes were compared, immediately and, after the passage of 24 h and 48 h. The obtained results indicate that the elasticity of the fabric as well as the geometry and point angle of the spike are effective on the penetration resistance. According to the outcomes, 55% increase in the presence of elastic yarn in the fabric structure has led to a growth in fabric's strength (approximately 21%) and a decrease in tensile modulus (about 15%). In addition, a sample with a higher tensile modulus had a higher penetration force and a lower penetration depth and energy. In addition, the geometry of the utilised spikes is an influential factor in the penetration performance and fabric resistance, including penetration force, penetration depth, and penetration energy. In case of about 38% diminish in the spike point angle, the resistance to penetration decreases around 40%.