热轧非织造布拉伸各向异性的分析

The Analysis of the Mechanical Anisotropy of the Thetmo-calender Bonded Nonwovens

本文由实验分析得出梳理并行铺网热轧粘合非织造布的单向拉伸破坏机理和力学各向异性情况:在不同方向单向扭伸非织造布时存在三种破坏机理——即纤维从粘合区被抽拔出,纤维沿粘合区边界断裂以及粘合区内部解体,而且不同方向的主导作用机理不同。结合理论分析发现:非织造布的拉伸弹性模量不符合正交各向异性板理论,而其断裂强度的各向异性却可用单向纤维增强复合材料强度的最大应变能理论进行预测,并可按最大应力理论预测不同方向单向拉伸时非织造布的主导破坏机理。

The paper analyzes the tensile failure mechanism and the mechanical anisotropy of thermo-calender bonded nonwovens from parallel-laid carded web.When the nonwovens are stretched in different directions three failure ways are observed,i.e.,the pulling out of the whole fibers from the bonded areas,the breaking of the fibers in the boundary of the bond areas as well as the failure of bonds.It is found that the anisotropy of the tensile elastic modulus of the nonwovens can not be predicted by the theory of orthotropic plate material.But the anisotropy of their tensile strength can be predicted by the maximum strain energy theory used for the fiber reinforced composite materials,and the theory can also be used to predict the failure ways when the nonwoven being stretched in any direc- tion.