Penetration resistance force of sandwich panels composite with kenaf foam as a core material against deformable projectiles

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.