Mechanical properties of titanium-5083 aluminium alloy friction joints

Abstract

The influence offriction welding and post-weld heat treatment on the tensile strength and metallurgical properties of the dissimilar friction joints between commercially pure titanium and type 5083 aluminium alloy base materials was investigated. The tensile strength of as welded joints was highest when a high friction pressure was applied in conjunction with afriction time of 0.5 s. There was no evidence of inter metallic formation at the bondline in the as welded joints produced using a friction time of 0.5 s. However, a 200 nm thickness intermetallic layer formed in as welded joints produced using a longer friction time (3 s) and in dissimilar joints post-weld heat treated at 450°C for 3.6 ks. It is suggested that the intermetallic layer comprised a mix of τ-Al (Ti₂Mg₃AI₁₈), Mg₂A1₃, and Al₃ Ti phases. The critical intermetallic layer width in Ti-5083 aluminium alloy joints was much less than that found in dissimilar Ti-304L stainless steel and pure Ti-pure Alfriction welds.