Investigating the effect of Nylon 6.6 electrospun nanofiber mats and punch—Die clearance on the damaged area and residual strength of punched glass/epoxy composite laminates

Abstract In this study, interleaving electrospun Nylon 6.6 nanofibers in the laminate was utilized to improve interlaminar properties of glass/epoxy composite during punching and as a solution to this issue. In order to do so, virgin and nano modified samples are produced and punched and the results are compared to determine the effect of nanofibers on the damaged area as well as the three‐point bending residual strength (carried out on both penetration and exit sides) of the punched laminate. Furthermore, punch—die clearance was also varied to investigate the range in which the nano modification improves the outcome of the process on the laminated composite. According to results of this study, using of Nylon 6.6 nanofibers between composite layers causes significant decrease in the damaged area up to 50%. Also, in both virgin and nano modified laminates, increasing the punch—die clearance increases the damaged area up to 50% and reduces the residual strength of the laminates up to 17%. In addition, nano modified laminates, the residual strength increased up to 28% and 22% for three‐point bending tests carried out on both punch penetration‐ and exit‐side samples, respectively. This is due to the fact that the punch exit‐side contains more damage compared to the penetration‐side. Highlights Toughening glass/epoxy laminates using electrospoon Nylon 6.6 nanofibers. Decreasing the damage area occur in the punching of composite laminates. Decreasing the damage area in punching by decreasing the punch‐die clearance. Increasing the strength of punched laminates by applying nanofibers.