Compression after impact characteristics of carbon fiber reinforced aluminum laminates

Abstract

The influence of layer structure and resin rich (polyester veil cloth) layers which were used for enhancement of interfacial bond adhesion on the compression after impact response of carbon fiber reinforced aluminum laminates (CARALL) was investigated in this research study. The addition of resin rich layers at interfaces of CFRP and aluminum layers shows significant reduction in delaminated area (40–50%) due to crack bridging effect. The residual compressive strength of CARALL laminates was increased by 30–35% as a result of reduction in delamination area. Excessive damage was found in CARALL-B FMLs during impact events as compared to CARALL-A FMLs. Thus, the Compressive residual strength of these laminates was lower as compared to standard CARALL-A laminates having aluminum layers placed exterior to CFRP layers. Numerical simulations were performed by utilizing commercially available finite element (FE) code, LS-DYNA to predict the CAI response of these laminates. Compressive residual strength vs. delamination area results showed good correlation between experimental and FEA results for CARALL-A and CARALL-B FMLs at lower energy levels (14–21J) but diverged at high impact energy level (31J). Numerical simulation was found to successfully capture the location and initiation of compressive buckling in specimens.