Pengaruh Fraksi Volume Face Plate terhadap Kekuatan Impak Komposit Honeycomb Sabut Kelapa
Abstract
The face plate of a sandwich composite receives the impact load first and transfers it to the core, so its proportion within the structure governs how much energy the whole structure can absorb. This study examines the effect of face plate volume fraction on the impact energy and impact strength of a honeycomb composite reinforced with coconut coir fibre. Face plate volume fractions of 30%, 40% and 50% were tested while the honeycomb core fraction was held at 30%. Each specimen combined two 20.1 mm wide, 2 mm thick face plates with two 10 mm high, 2 mm thick cell walls, giving a cross-sectional area of 120.4 mm². Testing followed the Izod method of ASTM D256 on an XJ-300A pendulum tester with a 29.4 J capacity released from 150°, using three specimens per fraction. Mean absorbed energy was 9.80 J at 30%, 15.67 J at 40% and 14.67 J at 50%, giving impact strengths of 0.0814, 0.1301 and 0.1218 J/mm². Raising the fraction from 30% to 40% increased impact strength by 59.9%, while a further rise to 50% reduced it by 6.4%. The relationship is therefore non-linear, and 40% gave the highest value among the fractions tested. One-way analysis of variance gave F(2,6) = 3.51 (p = 0.10), which falls short of significance at the 5% level, so the result is best treated as a strong indication rather than a settled optimum.
References
Fachreza, M.F., 2025. Analisa kekuatan tarik komposit resin polyester yang diperkuat serat serabut kelapa. Skripsi. Bangka Belitung: Politeknik Manufaktur Negeri Bangka Belitung.
Thyavihalli Girijappa, Y.G., Mavinkere Rangappa, S., Parameswaranpillai, J. dan Siengchin, S., 2019. Natural fibers as sustainable and renewable resource for development of eco-friendly composites: a comprehensive review. Frontiers in Materials, 6, pp.1-14.
Siregar, A., 2021. Pemanfaatan serat alami (sabut kelapa) sebagai alternatif bahan komposit pada spakbor depan motor. Skripsi. Pekanbaru: Universitas Islam Riau.
Rahmadhany, S., 2025. Pengaruh variasi fraksi volume serat sabut kelapa dan suhu perendaman alkali terhadap sifat komposit untuk aplikasi pembuatan badan perahu. Skripsi.
Zarrouk, T., Jeyar, M., Salhi, J.-E. dan Barboucha, M., 2026. Numerical investigation of low-velocity impact response of Nomex honeycomb sandwich structures: effects of core density, face-sheet thickness, and impactor geometry. Applied Mechanics, 7 (3), artikel 56.
Ashraf, W., Ishak, M.R., Khan, T., Sebaey, T.A., Singh, B. dan Alshahrani, H., 2024. Study of impact performance of composite sandwich structure fabricated partially with natural fiber facesheet. Polymer Composites, 45 (4), pp.3422-3435.
Gundara, 2019. Sifat tarik, bending dan impak komposit serat sabut kelapa-polyester dengan variasi fraksi volume. JMPM: Jurnal Material dan Proses Manufaktur, 3 (1), pp.10-19.
Shifa, S.S. dan Zhang, N., 2026. Progress and perspectives on plant-based natural fiber-reinforced polymer composites: structure-property relationships and emerging design strategies. Journal of Polymer Research, 33 (6), pp.1-5.
ASTM International, 2023. Standard test methods for determining the Izod pendulum impact resistance of plastics (ASTM D256-23e1). West Conshohocken, PA: ASTM International.
Thomas, R.J. dan Sorensen, A.D., 2018. Charpy impact test methods for cementitious composites: review and commentary. Journal of Testing and Evaluation, 46 (6), pp.2422-2430.
