%0 Thesis
%9 S1
%A Fikrananda, Bagus
%A UNIVERSITAS SULTAN AGENG TIERTAYASA,
%A FAKULTAS TEKNIK,
%A JURUSAN TEKNIK MESIN,
%B Teknik Mesin
%D 2026
%F eprintuntirta:59171
%I Fakultas Teknik Universitas Sultan Ageng Tritayasa
%K Adhesive Epoxy, FTIR, Kekuatan Geser, Perendaman Air Laut  Epoxy Adhesive, FTIR, Seawater Immersion, Shear Strength
%P 83
%T PENGARUH VARIASI PERENDAMAN AIR LAUT TERHADAP KEKUATAN GESER ADHESIVE EPOXY PADA SAMBUNGAN TUMPANG TUNGGAL ALUMINIUM
%U https://eprints.untirta.ac.id/59171/
%X In the modern era, the use of epoxy adhesives as a material joining method has been increasingly applied due to their advantages over conventional joining techniques. However, in certain applications, adhesive joints are often exposed to aqueous environments such as seawater, which may affect their mechanical properties. Therefore, this study aims to investigate the effect of seawater immersion duration on the shear strength of epoxy adhesive joints on aluminum 6061, as well as to analyze changes in the chemical structure of the adhesive using Fourier Transform Infrared (FTIR) spectroscopy. In this study, single lap joint specimens were prepared using epoxy adhesive and subsequently immersed in seawater for different durations, namely 0 weeks, 1 week, and 2 weeks. After immersion, the specimens were dried and subjected to shear testing using a Universal Testing Machine in accordance with ASTM D1002. FTIR analysis was conducted to examine changes in functional groups resulting from seawater exposure. The results indicate that seawater immersion significantly affects the shear strength of epoxy adhesive joints. The average shear strength of specimens without immersion was 1.81 MPa, which decreased to 1.624 MPa after 1 week of immersion due to water absorption that induced plasticization of the epoxy matrix. In contrast, immersion for 2 weeks resulted in a significant increase in shear strength to 5.443 MPa. This improvement is attributed to a post-curing process promoted by the presence of water. FTIR results showed no changes in functional groups, indicating that no chemical degradation occurred, and the observed differences were limited to variations in transmittance, which reflect changes in the physical condition of the polymer network. Therefore, seawater immersion for a certain duration does not necessarily reduce the shear strength of epoxy adhesives, but may enhance it through a post-curing mechanism.
%Z Dalam era modern saat ini, penggunaan adhesive epoxy sebagai metode penyambungan material semakin banyak diterapkan karena memiliki berbagai keunggulan dibandingkan metode penyambungan konvensional. Namun, dalam aplikasi tertentu, sambungan adhesive sering terpapar lingkungan berair, seperti air laut, yang berpotensi memengaruhi sifat mekaniknya. Oleh karena itu, penelitian ini dilakukan untuk mengetahui pengaruh variasi lama perendaman air laut terhadap kekuatan geser sambungan epoxy adhesive pada aluminium 6061 serta menganalisis perubahan struktur kimia adhesive menggunakan pengujian Fourier Transform Infrared (FTIR). Pada penelitian ini, spesimen sambungan single lap joint dibuat menggunakan adhesive epoxy, kemudian direndam dalam air laut dengan variasi waktu 0 minggu, 1 minggu, dan 2 minggu. Setelah perendaman, spesimen dikeringkan dan diuji kekuatan gesernya menggunakan Universal Testing Machine sesuai standar ASTM D1002. Pengujian FTIR dilakukan untuk mengamati perubahan gugus fungsi akibat perendaman. Hasil penelitian menunjukkan bahwa perendaman air laut berpengaruh terhadap kekuatan geser sambungan epoxy adhesive. Kekuatan geser rata-rata pada spesimen tanpa perendaman sebesar 1,81 MPa, kemudian menurun menjadi 1,624 MPa pada perendaman 1 minggu akibat penyerapan air yang menyebabkan plastisasi. Namun, pada perendaman 2 minggu, kekuatan geser justru meningkat secara signifikan hingga 5,443 MPa. Peningkatan ini disebabkan oleh terjadinya proses post-curing lanjutan yang dipicu oleh keberadaan air. Hasil FTIR menunjukkan tidak adanya perubahan gugus fungsi, sehingga tidak terjadi degradasi kimia, dan perbedaan yang muncul hanya pada tingkat transmittance yang mengindikasikan perubahan kondisi fisik jaringan polimer. Dengan demikian, perendaman air laut dalam durasi tertentu tidak selalu menurunkan kekuatan geser adhesive epoxy, tetapi dapat meningkatkan kekuatan melalui mekanisme post-curing.