Experimental notched fracture resistance study for the interface of Al-Cu bimetal joints welded by friction stir welding

Strength and load-bearing capacity of dissimilar joints welded by friction stir welding is one of the most interesting subjects for optimizing this recently developed joining technique. Hence, in this article, dissimilar butt weldments of pure copper with Al5083 are manufactured with different welding parameters (including pin rotational and tool offset). Then rectangular beam specimens containing right angle notches in the interface of joints were prepared from the welded plates and tested under three-point bend loading to investigate the interface fracture strength of Al-Cu joints. The results showed the significant influence of welding parameters on the strength and load-displacement curves of the tested bimetals. It was shown that considering a suitable value for the offset of pin can increase the interface fracture strength. The highest fracture loads were achieved at moderately lower pin rotational speeds.