Deformation mechanism and synergistic optimization of structural parameters of staple-fiber-based tricomponent auxetic yarn based on numerical simulation

Composed of staple fibers and two kinds of continuous filaments, the tricomponent auxetic yarn possesses superior wear performances including favorable bulkiness, softness and skin-friendliness. It supports industrial continuous manufacturing and possesses broad application potential. In this work, a finite-element model of the proposed tricomponent auxetic yarn was established via Abaqus software. The effects of wrapping filament radius, elastic modulus, and winding pitch on the yarn’s auxetic behavior were systematically investigated via single-factor parametric analysis and orthogonal design. Meanwhile, physical yarn specimens were prepared and tested to verify the simulation accuracy and clarify the key dominant parameters of the yarn’s auxetic performance. The results demonstrate that the three structural parameters exert significant influences on the minimum Poisson’s ratio, and the order of influence priority is wrapping filament pitch > wrapping filament radius > wrapping filament modulus. With the increase in each single parameter, the minimum Poisson’s ratio of the yarn first decreases and then increases. The optimal parameter combination is determined as the wrapping filament radius of 0.05 mm, elastic modulus of 85 GPa, and winding pitch of 4.3 mm, which achieves the optimal minimum Poisson’s ratio of −2.54. Experimental results are in agreement with numerical simulation data. The proposed modeling and simulation method can provide a reliable reference for structural optimization and performance investigation of auxetic yarn materials.