A Binary Model For Impact Failure Analysis Of Fiber Reinforced Composites And Its Application

Fiber reinforced composites are widely used in defense engineering, aeronautics and astronautics due to their significant advantages, such as lightweight, high strength and stiffness to weight ratio. Study of the damage propagation and failure mechanism of fiber reinforced composites under impact load are always a hot topic in composite research area.In this thesis, the Binary Model of Textile Composites introduced by Cox et al. in1994was developed into a Binary Model for impact failure analysis of fiber reinforced composites with the damage and failure of material considered by user subroutine VUMAT on the platform of ABAQUS/Explicit.The model was utilized in the ballistic impact failure analysis of3D orthogonal woven composites, and the validity of the model was verified by comparing the residual velocities and velocity time history of the bullet obtained from the model to that of experimental and numerical results in existed reference. Then, the factors that influence the impact resistance of2D plain woven composites were analyzed by using the binary model, and the results revealed how the tow properties, friction coefficient, geometry of bullet and incident angle influence the residual velocity of bullet.Based on massive numerical analysis practices, technical details about the binary model for impact failure analysis of fiber reinforced composites are summarized, especially the best choice of the element type and material model of the tow elements, the plastic property and stiffness degradation model of the effective medium elements.The binary model for impact failure analysis of fiber reinforced composites developed in this thesis can provide the residual velocity of bullet, the velocity time history and the acceleration time history with relatively low computing cost. The model has important reference value for numerical analysis and engineering design of fiber reinforced composites.