A homogenized constitutive model for 2D woven composites under finite deformation: Considering fiber reorientation

Two-dimensional (2D) woven composites exhibit excellent mechanical properties along the fiber directions. The mechanical behaviors demonstrate nonlinearity in specific applications. Although plasticity methods can be applied to predict complex behaviors, however, fiber reorientation has been observed during finite deformation, indicating that the fiber directions are no longer along orthotropic material axes when the angle between fibers changes. The angular bisectors of two fiber directions can serve as the orthotropic material axes due to the rotational symmetries even in finite deformation scenarios. This study reports a homogenized nonlinear constitutive model based on the rotational symmetry axes, incorporating plasticity and fiber reorientation phenomena. The plasticity model contains a two-parameter flow potential and power function. Plastic deformations are computed using an explicit method. Fiber reorientation angles are computed both theoretically and numerically. The relationship between mechanical properties and fiber reorientation angles is studied using finite element method (FEM). Due to introduce of a novel approach to determining the strain and stress of 2D woven composites undergoing finite deformation, the proposed model should have potential in engineering predictions.