Effect of Arc Voltage, Welding Current and Welding Speed on Fatigue Life, Impact Energy and Bead Penetration of Aa6061 Joints Produced by Robotic MIG Welding

摘要

Aluminum alloys forming to AA6061 have a wide range of desirable properties which are used in different industries such as aircraft industry and other aerospace structures. The effect of processing variables on fatigue life, impact energy and bead penetration of AA6061 joints produced by MIG robotic welding process was analyzed in the present study. Different samples were obtained by employing arc voltages of 20, 23 and 26 V, welding currents of 110, 130 and 150 A, welding speeds of 50, 60 and 70 cm/min. After finishing of the welding process, the mechanical properties of the samples were evaluated by means of fatigue and impact test at room temperature and the depth of weld penetration was measured in all of geometrical specimens. Results were clearly illustrated that when heat input increases, fatigue life of weld metal decreases whereas impact energy of weld metal increases in first and then drops significantly. A linear increase in depth of penetration with increasing welding current and arc voltage was also observed. The biggest penetration in this investigation was observed for 60 cm/min welding speed.