Electronic Theses and Dissertation

Penelitian ini bertujuan untuk memanfaatkan limbah serat mesokarp sawit sebagai penguat komposit diharapkan dapat menjadi alternatif material teknik yang ramah lingkungan dan menganalisis pengaruh variasi komposisi serat limbah mesokarp buah sawit dan resin epoksi terhadap kekuatan tarik dan perilaku getaran bebas material komposit. Spesimen komposit dibuat menggunakan metode hand lay-up dengan perlakuan alkalisasi NaOH 5% pada serat. Variasi komposisi fraksi volume yang digunakan meliputi E100 (100% resin), E7030 (70% resin : 30% serat), E6040 (60% resin : 40% serat), dan E5050 (50% resin : 50% serat). Pengujian sifat mekanik dilakukan melalui uji tarik berdasarkan standar ASTM D3039, sedangkan analisis respons dinamis dilakukan melalui uji getaran bebas mengacu pada standar ASTM E756-05 menggunakan sensor akselerometer. Hasil penelitian menunjukkan bahwa penambahan serat mesokarp sawit menurunkan tegangan tarik maksimum dibandingkan matriks epoksi murni. Nilai tegangan tarik tertinggi diperoleh pada spesimen E100 sebesar 46,54 MPa, sedangkan pada komposit berpenguat serat mengalami penurunan akibat ikatan antarmuka (interfacial bonding) yang kurang sempurna. Namun, penambahan serat secara signifikan meningkatkan kekakuan material, di mana Modulus Elastisitas tertinggi dicapai oleh variasi E5050 sebesar 5.760,29 MPa. Pada pengujian getaran, variasi E5050 menunjukkan performa dinamis terbaik dengan frekuensi pribadi (natural frequency) tertinggi sebesar 148 Hz dan rasio redaman (damping ratio) terbesar senilai 0,03315. Penelitian ini menyimpulkan bahwa variasi E5050 merupakan komposisi paling optimal ditinjau dari aspek kekakuan dan kemampuan redaman getaran, meskipun memiliki kekuatan tarik yang lebih rendah dibandingkan resin murni.

This study aims to utilize palm oil mesocarp fiber waste as a composite reinforcement, which is expected to serve as an environmentally friendly alternative engineering material, and to analyze the effect of variations in the composition of palm oil mesocarp fiber waste and epoxy resin on the tensile strength and free vibration behavior of composite materials. Composite specimens were fabricated using the hand lay-up method, with the fibers subjected to an alkali treatment using 5% NaOH. The variations in volume fraction composition included E100 (100% resin), E7030 (70% resin : 30% fiber), E6040 (60% resin : 40% fiber), and E5050 (50% resin : 50% fiber). Mechanical properties were evaluated through tensile testing in accordance with ASTM D3039, while dynamic response analysis was conducted through free vibration testing based on ASTM E756-05 using an accelerometer sensor. The results indicate that the addition of palm oil mesocarp fibers reduces the maximum tensile stress compared to pure epoxy matrix. The highest tensile strength was obtained for the E100 specimen at 46.54 MPa, whereas fiber-reinforced composites exhibited a decrease due to imperfect interfacial bonding. However, the incorporation of fibers significantly enhanced the stiffness of the material, with the highest elastic modulus achieved by the E5050 variation at 5,760.29 MPa. In vibration testing, the E5050 variation demonstrated the best dynamic performance, with the highest natural frequency of 148 Hz and the largest damping ratio of 0.03315. This study concludes that the E5050 variation represents the most optimal composition in terms of stiffness and vibration damping capability, despite having lower tensile strength compared to pure epoxy resin.