Stress corrosion cracking (SCC) is known as a major factor that should be considered in the assessment of welding joint structure integrity. Despite the promising and wide application of dissimilar metal joints, the currently available SCC mitigation technique of dissimilar metal joints is not adequate. The challenge is to obtain a good joint while different melting points exist. This article reports a novel SCC mitigation method on a brass–steel dissimilar metal joint by modifying the geometry of the surface. It is evidenced that the sharpened steel (α1 specimen) significantly improves the SCC resilience of the joint. The evaluation of SEM/EDS photos reveals that the α1 geometry induces a smaller pore area around brass–steel micro-joint interfaces which in turn produces stronger joints.

Failure at the welded joint can be occurs due to the Stress Corrosion Cracking (SCC) phenomenon. Dissimilar welding is more susceptible to SCC when compared to similar welding. This can be occurs because the material or metal that connected is nonhomogeneous material. which causes the material will be difficult to be combined perfectly. This study aims to determine the threshold stress (σ Th ) at the dissimilar welded joint between steel and brass which have SCC loads. Both materials were connected by the welding method by using a Capacitive Discharge Welding (CDW) welding machine. Surface preparation or surface treatment is applied to one of the basic materials (low carbon steel) to obtain optimal joint results. The welded joint was tested by using Constant Load Test (CLT) methods, which is engineered in such a way that the welded joint get the stress, corrosive environment (1M NHO 3 solutions) and voids produced by the weld joint itself. The result shows that the threshold stress of the dissimilar welding joint between steel and brass by the CDW method is 330 MPa.

In this article is presented dissimilar welding joint that joins steel and brass bars. Due to its varied melting point the welding process of dissimilar metal has a higher degree of difficulties. Naturally, welding process embeds residual stress and provides voids at least in micro scale. The voids then act as a trigger to develop initial cracks which will grow under external load. Once, the welding joint is exposed to corrosive environment, it will be susceptible to Stress-Corrosion-Cracking (SCC) failure. The quality of the welded joints is considered based on SCC resilience. Two parameters of the Capacitive Discharge Welding Joint which have prominent effects were evaluated: surface preparation and inputted energy. With a proper surface preparation it is hoped optimum welded joints can be obtained. The experiment results show that the oc1 surface preparation, i.e. the sharpened steel interface while the brass is kept on perpendicular edge, provides better performance under SCC load. Highest inputted energy (120J) always provides the longest duration for joint exposed to SCC load before the failure. The high inputted energy gives high heat to melt the interface which in turn produces compact joint at the interface.

Peningkatan jumlah penduduk di kabupaten fakfak mempegaruhi penggunaan bahan plastik di kehidupan manusia sebagai aktivitasnya. Namun, dengan seiring pemanfaatan plastik dalam waktu berkepanjangan dan volume penggunaan yang besar akan menghasilkan limbah plastik yang cukup banyak. Limbah plastik atau limbah padat merupakan barang buangan dan dapat bertahan hingga bertahun-tahun hal itu akan menimbulkan masalah seperti penumpukan limbah sampah plastik sehingga dapat menyebabkan penyakit serta pencemaran terhadap lingkungan sekitar. Untuk itu diperlukan suatu proses pengolahan limbah untuk menguruangi terjadinya penumpukan sampah plastik. Tujuan yang ingin dicapai pada penelitian ini yaitu untuk mengetahui proses pembuatan mesin pelebur dan pencetak paving block dengan jumlah kapasitas produksi pada paving block serta mengetahui analisa kekuatan uji tekan hasil paving block dari bahan dasar limbah plastik. Metode yang digunakan pada penelitian ini yaitu rancang bangun alat pelebur dan pencetak paving block berbahan dasar limbah plastik HDPE. Rancang bangun alat molder ini menggunakan sistem pengaduk pada tuas pemutar, serta limbah plastik HDPE sebagai bahan dasar paving block. Hasil dari penelitian ini yaitu berupa alat molder limbah sampah plastic serta hasil uji. Berdasarkan pada pengujian 1 diperoleh nilai kuat tekan (F’c) sebesar 36.50 MPa, pada pengujian ke 2 diperoleh nilai kuat tekan (F’c) sebesar 38.91 MPa dan pada pengujian ke 3 diperoleh nilai kuat tekan (F’c) sebesar 37.90 MPa. berdasarkan nilai rata-rata kuat tekan (F’c) diperoleh nilai sebesar 37.77 MPa. Rata-rata hasil uji kuat tekan pada paving block terdapat pada standar mutu A dengan kuat tekan sebesar 37.77 MPa yang diperuntukan untuk jalananKata kunci: Sampah Plastik HDPE; Alat Molder; Paving Block.