In this study, plate sandwich panels with fibre-reinforced polyurethane face and kenaf form core
under quasi-static indentation of small arm bullet (5.56 mm) were investigated experimentally. The
sandwich structure is comprised of two outer steel plates composite with kenaf foam as its core
material that was rigidly clamped on vertical orientation. Different percentages of kenaf in the foam
mixture (0%, 10%, 20%, and 30%) and thicknesses of the foam (15 mm, 30 mm, 45 mm) were used to
investigate the protective plate performance against ballistic impact. From this study, we have
demonstrated that the difference in indentation resistance between the sandwich panel and its
corresponding core material depends on the resistance force. We have also found that reinforced
form with 20% of kenaf with a thickness of 45 mm has the highest resistance behaviour. It can be
concluded that kenaf material can be used to reinforce polyurethane foam in enhancing the strength
and mechanical properties of the foam and armour