FEM Simulation Of Three-dimensional Angle Interlock Woven Composite Under Low-Velocity Impact

Three-dimentional textile structural composites have higher inter-laminar shear strength, fracture toughness and impact damage resistance tolerance than laminates because the reinforcement fibers run through the thickness direction.3D angle-interlock woven fabric can be classified into two types, layer to layer angle-interlock woven fabric and through-thickness angle-interlock woven fabric.3D angle-interlock woven composite has excellent mechanical properties. It is important to study the properties of impact resistance which play an important role in mechanical research of composites because of the wide potential applications in structure design and impact protection.In this paper, the mechanical properties and failure process of 3D angle-interlock woven composite under low-velocity impact was studied. The mechanical properties of 3D angel-interlock woven composite under low-velocity impact were tested at four different energies with Instron DynatupTM 9250 impact tester, and the load-displacement curves, displacement-time curves, failure mode were obtained. An unit cell model based on the microstructure of the 3D angle-interlock woven composite was established to investigate the low-velocity impact deformation and damage. In the unit cell model, the composite was simplified into a combination of resin, weft yarn and warp yarn to define the stiffness matrix and failure evolution of the material. Incorporated with the unit cell models, elasto-plastic constituve equations of the 3D angle-interlock woven composites, the maximum stress criterion and the critical damage area(CDA) failure theory was implemented as a user defined material law (VUMAT) with FORTRAN for finit element code ABAQUS/Explicit. The impact properties and failure modes calculated from FEM code ABAQUS were compared with those in experiment. Good agreement between FEM and experimental proves the effectiveness of the unit cell model and the VUMAT.This paper provides a method of experiment and prediction theory for the study of 3D angle-interlock woven composites under low-velocity impact, and will contribute to the design of composite structure and the exploitation of composites.