Influence Analysis of Shielding Gas Flow Rate and Purity Level Variation on GMAW Welding Process to Microstructure of Alumunium 5083

Aluminium is a commonly used material in construction and transportation industries. The advantages of using the aluminium material are its light weight, corrosion resistant, and the capability to form an alloy with another metal. Therefore, the aim of this research is to analyze the influence of shielding gas flow rate and purity level variation to mechanical properties and microstructure of the welded material. The welding process used on this research was the GMAW method. The material used was aluminium 5083 series with 300 mm x 150 mm x 8 mm dimensions. The shielding gases used were high purity (HP) and ultra-high purity (UHP) argon (Ar). The variations of shielding gas flow rate used were 16, 18, dan 20 litre/minutes. Based on the tensile test that has been done, the variation of UHP argon gas with 20 litre/minute flow rate had the best result with yield strength of 217,32 MPa and ultimate strength of 295,83 MPa. The result of the micro photos showed that the GMAW method produced small dots where the dots were Mg2Si formation, which the greater number of smaller size dot produced would increase the mechanical properties of  the material

Analisa Pengaruh Kecepatan Aliran dan Tingkat Kemurnian Gas Pelindung Pada Proses Las GMAW Terhadap Sifat Mekanik dan Struktur Mikro Sambungan Las Aluminium 5083

Aluminium merupakan material yang banyak digunakan dalam sebuah konstruksi dan industri transportasi. Salah satu keuntungan dari bahan aluminium sendiri adalah bobotnya yang relatif ringan, tahan terhadap korosi, serta kemampuannya membentuk paduan dengan logam lain. Oleh karena itu, penelitian ini dilakukan untuk menganalisis pengaruh variasi kecepatan aliran dan tingkat kemurnian gas pelindung terhadap sifat mekanik dan mikrostruktur dari material yang dilas. Proses pengelasan pada penelitian ini akan dilakukan dengan metode GMAW. Material yang digunakan adalah aluminium seri 5083 dengan dimensi 300 mm x 150 mm x 8 mm. Gas pelindung yang digunakan adalah argon (Ar) high purity (HP) dan ultra high purity (UHP). Adapun variasi kecepatan aliran gas pelindung yang digunakan antara lain 16, 18, dan 20 liter/menit. Dari pengujian tarik yang dilakukan, variasi laju alir gas argon UHP sebesar 20 liter/menit mendapatkan nilai yield strength tertinggi yaitu 217,32 Mpa dan ultimate strength sebesar 295,83 MPa. Hasil pengamatan foto mikro menunjukkan bahwa pengelasan dengan metode GMAW menghasilkan butiran-butiran kecil dimana butiran tersebut merupakan formasi pembentukkan Mg2Si, dimana dengan meningkatnya jumlah butiran tersebut dengan ukuran yang semakin kecil dapat meningkatkan sifat mekanik dari sebuah material. ================================================================================================= Aluminium is a common used material in a construction and transportation industries. One of the advatage by using the aluminium material is relatively has light weight, corrosion resistant, and the capability to form with another metal. Therefore, the aim of this research is to analyze the influence of shielding gas flow rate and purity level variation to mechanical properties and microstructure of the wleded material. The welding process on this research is using the GMAW method. The material used an aluminium 5083 series with 300 mm x 150 mm x 8 mm dimension. The shielding gases used argon (Ar) high purity (HP) dan ultra high purity (UHP). The variation of shielding gas flow rate used are 16, 18, dan 20 litre/minutes. Based on tensile test that has been done, the variation of argon UHP gas with 20 litre/minutes flow rate has maximum yield strength which is 217,32 Mpa and ultimate strength 295,83 MPa. The result of the micro photos shown that the welding by using GMAW method produces small dots where the dot is a form of Mg2Si, which the greater dot produced with a smaller size will increase the mechanical properties from the material