三组分螺旋拉胀纱的拉伸力学性能及影响

Tensile Mechanical Properties and Influence of Three component Helical Auxetic Yarn

构建力学模型是研究纱线力学性能的常用方法。建立了三组分螺旋拉胀纱的粘弹-塑性模型,以预测其拉伸应力-应变关系,并进一步探究纱线结构及负泊松比效果与力学性能之间的关系。基于拉伸断裂特性,建立了由Kelvin单元、Maxwell单元和线性弹簧组成的五元非线性粘弹性模型和简化为线性关系的塑性模型,以屈服点为分段点,构建了拉伸力学分段函数模型。通过引入修正系数,优化了模型的有效性,相关系数大于0.999,在此基础上,研究了初始螺旋角对拉伸力学性能的影响。该模型可用于预测三组分螺旋拉胀纱的拉伸性能,结果表明:以螺旋角为主要参数的纱线结构影响纱线的粘性系数和负泊松比值,进而影响纱线的力学性能和拉胀性能。

The construction of mechanical model is a common method to study the mechanical properties of yarns.A viscoelastic-plastic model was established to predict the tensile stress-strain relationship of the three component helical auxetic yarn.The relationship between yarn structure,negative Poisson's ratio effect and me-chanical properties was further investigated.Based on the tensile fracture characteristics,a five-element nonlin-ear viscoelastic model composed of Kelvin element,Maxwell element and linear spring and a plastic model sim-plified to linear relationship were established.Taking the yield point as the piecewise point,the piecewise func-tion model of tensile mechanics was constructed.By introducing the correction coefficient,the validity of the model is optimized,and the correlation coefficient is greater than 0.999.On this basis,the influence of the initial spiral angle on the tensile mechanical properties was studied.The model can be used to predict the tensile prop-erties of the three-component helical auxetic yarn.The results show that the yarn structure with spiral angle as the main parameter affects the viscosity coefficient and negative Poisson ratio of the yarn,and then affects the mechanical properties and auxeticity properties of the yarn.