Friction welding of cast-to-wrought aluminum alloys.

In friction welding of 5052 wrought alloy to high pressure castings of AC4C, several welding conditions and mechanical properties of welds were investigated. The conventional type of friction welding machine was used. On the 5052 alloy, fine grain structure resulting from disappearance of fiber one was observed closely near the weld interface and modified fiber one along the flow direction of burr at the heat-affected zone. While on the side of castings fine grain structure having no sign of cast one was observed closely near the weld interface. The hardness of both the annealed and the as received 5052 alloys at the weld interface had higher values than that of the castings. The highest tensile strength of weld joint could be obtained when friction time was 2 second, but it was lower than that of the base metals. And when friction time was 1 and 2 second the elongation of weld joints showed the similar values to that of castings. The impact values of the joint having a notch at the weld interface were inferior to that of the base metals.