Influence of water absorption on the mechanical properties of discontinuous carbon fiber reinforced polyamide 6

  • Hao PiaoEmail author
  • Yoshiaki Kiryu
  • Lubai Chen
  • Shinichiro Yamashita
  • Isamu Ohsawa
  • Jun Takahashi


Carbon fiber reinforced thermoplastics (CFRTP) have been developed to realize excellent formability and mechanical properties. Specifically, discontinuous CFRTP (DCFRTP) are promising candidates for decreasing production cost and for application to mass production. Polyamide 6 (PA6) is a promising matrix for CFRTP due to its good adhesion properties with carbon fibers (CFs). However, the degradation of the mechanical properties of CFRTP due to the hygroscopic properties of PA6 is an area of concern. Thus, an investigation of the effects of water absorption on the mechanical properties of discontinuous CF reinforced PA6 is necessary. Additionally, a theoretical prediction of the degradation in mechanical properties is useful to clarify the effect of the absorbed water. Therefore, in this study, the influence of water absorption on the mechanical properties of CFRTP was investigated by measuring the mechanical properties using a three-point bending test. In addition, the flexural modulus was calculated using the Timoshenko beam equation to predict the degradation due to water absorption.


Discontinuous carbon fiber ROS CTT CPT PA6 



Part of this study belongs to the Japanese METI project “The Future Pioneering Projects / Innovative Structural Materials Project” since 2013. The authors would like to express their sincere appreciation to the other project members who have provided valuable information and useful discussion. In addition, the authors would like to thank the Industrial Technology Center of Fukui Prefecture and Awa Paper MFG. Co., Ltd., who have provided useful materials.


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Copyright information

© The Polymer Society, Taipei 2019

Authors and Affiliations

  1. 1.Department of Systems Innovation, School of EngineeringThe University of TokyoTokyoJapan

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