EFFECT OF IMPACTOR DIAMETER ON THE RESIDUAL PROPERTIES OF IMPACT DAMAGED COMPOSITE PANELS

Carbon fiber reinforced polymer (CFRP), is widely used as a structural material in high-performance applications. Even though CFRP has very high strength in the fiber direction, the material response to in-plane impact damage is weak. The post impact residual strength - also referred to as Compression strength after Impact (CAI) - of the damaged composites panels are commonly correlated with the kinetic energy of the impactor. The shape of the impactor also affects the damage patterns, and hence the residual strength. The effect of radius of the impactor on residual strength and residual stiffness CFRP laminates is studied. Low velocity impact with same initial kinetic energy and different impactor diameters simulated using dynamic explicit finite element analysis. Neither the delamination patterns nor the residual strength properties show any clear correlation with the impactor diameter. The energy absorbed during the impact was found to be a direct measure to estimate residual mechanical properties.