In polymer-based nanocomposites, carbon nanofibers have been used to improve mechanical properties in various applications. In this research, the tensile properties of carbon nanofibers have been used to create carbon-epoxy nanocomposite and improve the mechanical properties of epoxy nanocomposite, and the effect of the weight percentage of carbon nanofibers on the mechanical properties of epoxy nanocomposite has been investigated. Epoxy with weight percentages of 1.0, 0.5 and 1.5 carbon nanofibers was produced and their mechanical properties were investigated. The results showed that the use of even a small percentage of carbon nanofibers can lead to the improvement of mechanical properties. Considering the fact that the non-uniform distribution of these nano-fibers in the epoxy matrix on the one hand and also the lack of acceptable adhesion between these two phases are critical issues that lead to the formation of lumps in the matrix and finally the loss of mechanical properties in will find. پرونده مقاله