Structure Effect on Damage Evolution of 3-D Angle-interlock Woven Composites Under Low-velocity Impact By Coupled DIC Analysis and Numerical Study

Impact damage distribution is the key to designing composite structures with high-impact damage tolerances. Here we report the impact damage initiation, evolution and distribution in three-dimensional (3-D) woven composites from inner and surface deformation. The ultimate peak force of 48 kN was predicted with a spring-mass-dashpot model. A novel damage-tracking algorithm was developed to observe the evolution of surface damage and quantify the damage characteristics. We found that the woven structure has a great effect on the damage propagation and the distribution of strain and stress. The high deformation resistance, the large stress value and the wide stress distribution on the weft yarn are attributed to its high strength and straight arrangement. The crimp of warp yarn limits the stress distribution which is easy to cause stress and damage concentration. With the warp yarn breakage, more interfacial damage spreads on the weft yarn.