Effects of manufacturing and face/core bonding on impact damage in glass/polyester–PVC foam core sandwich panels

Effect of manufacturing on impact damage behaviour was investigated in typical marine composites of E-glass fibre/polyester/PVC foam core sandwich structures. Face/core bonding was performed using two different adhesives and the matrix resin. Low velocity impact response of the sandwich plates was investigated using an instrumented impact drop tower. Impact damage size was estimated by visual inspection or by the ultrasonic C-scan. Failure characteristics indicate that, in terms of the frequency of core fracture, wet-lay-up process is superior to adhesive bonding of the face to the foam core. Damage initiation and failure mechanisms were recorded by high-speed photography and related to the load–time plots. The type of face core bonding did not affect the delamination threshold load (DTL) of the sandwich structure, which depends on the properties of the face laminate. DTL was found ca. 2.5 kN. Morphology of the face/core interfaces was examined using a SEM microscope.