Abstract:

In this experimental study, we investigated the effects of core yarn diameter and cover yarn type on the mechanical properties of composite yarns produced using a hollow spindle twisting machine according to the method of covering. Composite yarns containing stainless steel (SS) metal wires with diameters of 50 μm and 100 μm were produced with seven different cover yarns varying in their raw material and structure. These cover yarns were as follows: polypropylene, cotton, core-spun polyester/cotton, continuous filament polyester, continuous filament polyamide 6.6, core-spun polyester/polyester, and polyester cut fibre yarns. The mechanical properties measured were tensile behaviour and stiffness. According to the findings of the statistical analyses performed using the experimental values, the core yarn diameter, cover yarn type and the interactions of these factors were all significant factors affecting the tenacity, elongation at break, work of rupture and stiffness properties of the composite yarns. Composite yarns containing continuous filament polyamide 6.6 cover yarn showed higher tenacity values, while the maximum elongation at break was obtained for the composite yarns containing continuous filament polyester cover yarn. Both polyester and polyamide 6.6 possessed higher work of rupture values among the other types of cover yarns. An increase in the SS wire diameter resulted in a significant increment in stiffness values. The results of this study implied that it is important to give importance to component yarn types when designing composite yarns with desired physical properties.