Failure behavior of quasi-isotropic carbon fiber-reinforced polyamide composites under tension

Abstract

In this paper, the microscopic failure behavior of quasi-isotropic carbon fiber-reinforced polyamide-6 (CF/PA6) laminates under tension was investigated experimentally. Laminates of two layups, namely [45°/0°/−45°/ 90°]_s and [45°/0°/−45°/ 90°]_2s, were made from CF/PA6 tapes of two different manufacturers and then subjected to tensile testing. Crack initiation and progression on the polished free edge of specimens were examined using optical microscopy, under several load levels. Crack growth behavior through the specimen width was also traced by observing the crack configurations in different sections in the specimen width direction. The effects of the spatial distribution of fiber on the microscopic damage events were elucidated. The difference in failure behavior between the present CF/PA6 laminates and conventional thermosetting CF/Epoxy laminate is discussed.

Keywords:

• thermoplastic composites
• fiber distribution
• tensile test
• damage behavior

Acknowledgements

The first author would like to thank Ministry of Higher Education Malaysia (MOHE) for the PhD scholarship. The authors would also like to thank Mr. Hiroshi Kushiku from NHK Spring Co., Ltd. for providing the materials for this research.