Alumina reinforced nanofibers used for exceeding improvement in mechanical properties of the laminated carbon/epoxy composite

Abstract In the present research, mechanical properties of a conventional carbon/epoxy composite were improved via incorporating reinforced polyacrylonitrile (PAN) nanofibers between the carbon fabric layers. Alumina (Al 2 O 3 ) nanoparticles were employed to improve mechanical properties of the PAN nanofibers. Morphological studies of the nanofibers by scanning electron microscopy (SEM) showed increasing the alumina nanoparticles (more than 1 wt%) leading to nanoparticle agglomeration. However, the transmission electron microscopy (TEM) confirmed no alumina agglomeration occurred at 1 wt%, which the highest mechanical properties of the nanofibers was achieved for this nanoparticle content. Statistical analysis of the obtained both in-plane and out-of-plane mechanical properties on hybrid composites (carbon/epoxy composite containing nanofibers) showed that the composite reinforced with Al 2 O 3 -PAN nanofibers had greater mechanical properties rather than that of control composite (without the nanofibers) even the hybrid composite containing the same amount of neat PAN nanofibers. Al 2 O 3 -PAN nanofiber reinforced composite improved their neat PAN counterparts in tensile strength and flexural strength by 8 and 7%, respectively. Furthermore, Compared to the control composite the enhancements resulting from the Al 2 O 3 -PAN nanofibers incorporation were obtained at 23 and 20%, for tensile and flexural strength, respectively.