Frank Hunt

Friction Stir Welding of Magnesium Oil Pan

In this research, the feasibility of FSW dissimilar magnesium alloys was investigated. Specifically, die cast magnesium MRI-153M and AZ31 (plate) were butt-welded using the FSW technique. The effects of weld parameters (tool rotation (rpm) and weld speed) on the weld quality have been quantified in terms of hardness profile across the weld as well as tensile strength. Weld surface and cross section were also analyzed. Tensile testing showed that the welded material failed in the base material (MRI-153M) and not in the weld region. Weld cross section analysis showed void free welds were achieved at weld speeds up to 500 mm/min. Furthermore, a smooth and glossy surface ripple appeared on the weld beads and only a small amount of burr was observed. The Mg alloys were then welded together in an experimental oil pan cast in the USCAR-Magnesium Powertrain Cast Component Project. Finally, the oil pan assembly was successfully water bath-leak tested in water bath at 82.7KPa (12 psi) pressure for 3 minutes to validate the applicability of FSW.