PENGARUH FRAKSI VOLUME KOMPOSIT HYBRID SERAT KARBON – SERAT RAMI TERHADAP UJI IMPACT DAN UJI PENYERAPAN AIR UNTUK APLIKASI PROTOTIPE LAMBUNG KAPAL

Abstract

The development of composite materials is rapidly advancing due to their advantages of being lightweight, strong, and corrosion resistant, making them widely used in the shipping industry. Carbon fiber is known for its high strength but is relatively expensive, while hemp fiber, as a natural fiber, is more economical and environmentally friendly. The use of hemp fiber has the potential to support the development of sustainable materials in Indonesia, which is rich in biological resources. This study aims to analyze the effect of variations in the composition and arrangement of carbon fiber and hemp fiber in hybrid composites on impact strength and water absorption for prototype ship hull applications. The method used is quantitative experimentation with a vacuum infusion process. Impact testing refers to ASTM D5942-96 and water absorption to ASTM D57-88. It was conducted from August to December 2025 at the Surabaya State University Laboratory and Malang State Polytechnic. The results showed that an increase in the volume fraction of carbon fiber increased energy absorption and decreased water absorption. The best variation was obtained in variation 1 with a composition of 35% carbon fiber, 15% hemp fiber, and 50% matrix with an absorption energy of 9.743 J, impact strength of 0.11664 J/mm², and water absorption of 2.62%. Conversely, variation 4 with a composition of 15% carbon fiber, 35% flax fiber, and 50% matrix produced the lowest values with energy absorption of 3.419 J, impact strength of 0.03897 J/mm², and water absorption of 17.19%.