On delamination threshold loads in low velocity impact on glass-carbon/epoxy composites

摘要: When a structure is accidentally impacted by an object, (e.g. dropping tool) it may be important to know if the impact likely cause serious damage in structure. The easiest way solve this compare energy with threshold of Thus, necessary find which depends on properties material and boundary conditions. In present work problem delamination load assessment was studied for epoxy laminates reinforced woven glass-carbon laminates. behaviour symmetrical unsymmetrical glass E/carbon C laminate (E/C/E/C/E E/E/C/E/C). Instrumented static indentation tests were used. rebound conducted 100 mm square specimens standard instrumented weight tower Ceast Dartester. Indentation performed using same samples supports geometry as tests. acoustic signal used assess deflection corresponding first laminate. Damaged examined SEM. approximate projected maximum area assessed plotted against (Fig. 6). experimental results obtained show (Figs 5, 6) that, similar quasi-isotropic fibre reinforcement, glass/carbon/epoxy there exists sudden jump delaminations from zero certain value (100 mm). found 1.5 J independent stacking sequence. near-thethreshold glass-carbon/epoxy consists fibre/matrix debonding. Good correlation (indentation) measurements confirm that prediction quasi instead test practical useful.