Tensile Characteristics of Dual Sheath Single Core Hybrid High-performance Yarn

The concept of hybrid yarn is gaining popularity for its potential for several protective aspects, such as thermal protection, cut protection and so forth. Twelve distinct varieties of hybrid yarns with a core and two continuous filament sheaths were spun in this instance. These twelve yarns were primarily divided into two sub-divisions, one with glass fiber and the other with stainless steel (SS) in the core. Ultra-high molecular weight polyethylene (HPPE) was regarded as the outer sheath, and polyester yarn was the inner sheath layer. Two distinct varieties of HPPE yarns were chosen for performance comparison: 200D and 400D HPPE and 300D hard particle-impregnated HPPE (HPI-HPPE). Different twist directions of the sheath layers were also kept under consideration. The linear densities of the core yarn and outer sheath yarn were varied to observe the final hybrid yarn tensile properties with a fixed twist density (400 twists per meter). ASTM D2256 was followed to evaluate the tensile performance on the Instron universal tensile strength tester. The breaking strength and tenacity for S-Z twisted hybrid yarns were higher than for S-S twisted yarns. SS core yarns were finer than glass core yarns, which showed higher tenacity, modulus, and load-bearing capacity. Conversely, the strain percentage at maximum load was higher for glass core yarns than for SS yarns because of multiple phase cracking of glass core yarn. The HPI-HPPE yarns showed much lower tensile values than HPPE yarns. The reason was revealed by the surface morphology and CV% of diameter as an extensive necking tendency due to hard particle impregnation in HPI-HPPE yarn.