Effect of carbon nanotube on the mechanical properties of short carbon fiber reinforced polyether-ether-ketone

Additive manufacturing provides a quick and cost-effective way for the fabrication of complex composite structures. Additively manufactured short carbon fiber reinforced polyether-ether-ketone (SCF/PEEK) is a promising thermoplastic composite material due to its excellent designability, ease of manufacture, and good recyclability. However, the mechanical properties of 3D printed SCF/PEEK are unsatisfactory due to the layer-by-layer forming process. In this study, CNTs were introduced to 3D printed SCF/PEEK, and the influence mechanism of CNTs on the mechanical properties was analyzed and discussed in depth. The results showed that the introduction of CNTs could effectively enhance the tensile modulus of 3D printed SCF/PEEK, whilst it led to a decrease in the tensile strength and interlaminar shear strength of the composites. This was mainly related to the poor dispersion and agglomeration of CNTs. The modulus of 3D printed SCF/PEEK reached about 5.17 GPa, representing a 95.1% increase.