Multi‐Angle Low‐Velocity Impact Response of Concave 3D Angle‐Interlock Woven Composites

ABSTRACT The 3D angle‐interlock woven composites (3DAWCs) have been widely used in aerospace, defense, and automotive fields due to their excellent impact resistance. The aim of this paper was to explore the influence of woven structure and impact angle on the impact response of concave 3DAWCs. Low‐velocity impact tests on four types of the concave 3DAWCs were conducted under impact energy of 25 J at impact angles of 90°, 75°, and 60°. The impact damage morphology on the surface and inside after the impact was characterized by using a 3D profilometer and scanning electron microscope (SEM). The results indicated that concave composites with higher weft content led to the 39.9%, 42%, and 27.1% increases in peak load, as well as the 54.1%, 51.9%, and 15.7% rises in bending stiffness compared with conventional 3DAWC at three impact angles. The damage on the surface and inside of the composites with a large proportion of weft yarn was relatively small. The decrease of the impact angle reduced the peak load and bending stiffness of the composites but increased the contact duration and enhanced the energy rebound performance. The reduction of the impact angle caused the damage morphology of the composite to change from indentation to friction scratch.