OUT-OF-PLANE COMPRESSIVE RESPONSE OF ADDITIVELY MANUFACTURED CROSS-PLY COMPOSITES

Digital manufacturing is employed to 3D print continuous Carbon, Glass and Kevlar fibre reinforced composites in [0°/90°] layup sequence. These 3D printed composites subjected to quasi-static, out-of-plane compression loading. The out-plane compressive strength of the 3D printed Carbon and Glass fibre reinforced composites were independent of specimen size. By contrast, the Kevlar fibre composites have shown a pronounced size effect upon their out-of-plane compressive strength. By using pressure film measurements, it is shown that there exists a shear-lag zone at the periphery of the specimen which governs the out-of-plane compressive strength of the 3D printed composites. To gain further insights on the experimental findings, Finite Element (FE) simulations are carried out using a pressure-dependent crystal plasticity framework. An analytical model is also developed to link the out-of-plane compressive strength of the 3D printed composites to their mechanical properties. Both FE and analytical model accurately predict the out-of-plane compressive strength of 3D printed composites.