Impact characteristics of composite panel stitched by I-fiber process

Impact damage generated during manufacturing processes or operations are undetectable by the naked eye, hard to repair, and decrease the lifetime of a product. The damage area can be reduced by reinforcing the z-directional strength. Z-pinning and stitching are typical z-directional reinforcement methods. The I-fiber stitching process is a very promising technology that combines the advantages of Z-pinning and a conventional stitching process. In this paper, composite panels stitched by the I-fiber process were manufactured, and impact tests were performed. The damage areas and compressive strengths after impact were measured and compared with an unstitched panel. A reinforcing area of 50 x 50 mm was reinforced in a composite panel having a stacking sequence of [45/0/ - 45/90](3s), and the impact tests of six composite panels with different stitching densities and patterns were tested and evaluated.