Pengaruh Kuat Arus Listrik Dan Laju Alir Gas Pelindung Terhadap Struktur Mikro Dan Kekuatan Tarik-Geser Sambungan Las Tig Logam Tak Sejenis Alumunium Paduan 5052-Baja Galvanis Dengan Filer Al-Si 4043

Abstract

Joining dissimilar metals by TIG welding was an increasing trend in automotive assembly. Effect parameter of welding such as welding current and shielding gas flow rate to microstructure and tensile-shear strength of tungsten inert gas weld joint dissimilar metals alumunium 5052 and galvanized steel with Al-Si 4043 was determined. Welding speed was kept constant in this research. The parameter of welding current was used in this experiment were 70; 80; and 90 A and shielding gas flow rate 10; 12; and 14 litre per minute. As a result of the experiment, it was determined that increasing of welding current and shielding gas flowrate cause grain size become smaller in weld area, HAZ of aluminum, and HAZ of galvanized steel. The biggest grain size in weld area, HAZ of aluminum, and HAZ of galvanized steel are 73,34; 117,7; dan 47,7 μm respectively.  The increasing of tensile-shear strength caused by increasing of shielding gas flowrate. The highest tensile-shear strength of weld got in welding current 80 A and shileding gas flowrate 14 litre/minute is 95,34 MPa. The lowest tensile-shear strength got in welding current 70 A and shielding gas flowrate 10 litre/minute is 59,67 MPa.

keyword : Tungsten Inert Gas welding, Dissimilar metal, Welding current, Shielding gas flow rate, microstructure, compound, Tensile-shear strength