Effect of stitching on impact and interlaminar properties of graphite/epoxy laminates
- Univ. of Florida, Gainesville, FL (United States). Dept. of Aerospace Engineering, Mechanics, and Engineering Science
Effects of through-the-thickness stitching on the impact damage resistance, impact damage tolerance and interlaminar fracture toughness (Mode I and Mode II) of plain woven and uniweave textile graphite/epoxy laminates are investigated. The laminates were manufactured using resin-infusion-molding and resin-transfer-molding processes. Kevlar{reg_sign} and glass yarns of different yam numbers were used for stitching. Static Indentation-flexure (SI), Compression-After-Impact (CAI), Double-Cantilever-Beam (DCB) and End-Notched-Flexure (ENF) tests were conducted. Stitching did not have any significant effect on impact damage resistance. However, stitching leads to significant improvement (25-40%) in impact damage tolerance as measured by CAI strength and impact damage area. Mode I fracture toughness as characterized by critical strain energy release rate (G{sub Ic}) was found to increase by at least an order higher (15--30 times) than the unstitched laminates. Mode II fracture toughness (G{sub Ic}) increased by 5--15 times over the unstitched laminates. New methods to estimate Mode 11 critical strain energy release rate in the stitched laminates are presented.
- OSTI ID:
- 89849
- Report Number(s):
- CONF-9409291--; ISBN 1-56676-220-0
- Country of Publication:
- United States
- Language:
- English
Similar Records
Delamination behavior of carbon fiber/epoxy composite laminates with short fiber reinforcement
Effect of Mixed-Mode Ratio on Cryogenic Interlaminar Fracture Toughness of Woven Fabric Glass/Epoxy Laminates