MECHANICAL-PROPERTIES OF TITANIUM-5083 ALUMINUM-ALLOY FRICTION JOINTS

The influence of friction welding and post-weld heat treatment on the tensile strength and metallurgical properties of the dissimilar fricti on joints between commercially pure titanium and type 5083 aluminium a lloy base materials was investigated. The tensile strength of as welde d joints was highest when a high friction pressure was applied in conj unction with a friction time of 0.5 s. There was no evidence of interm etallic formation at the bondline in the as welded joints produced usi ng a friction time of 0.5 s. However, a 200 nm thickness intermetallic layer formed in as welded joints produced using a longer friction tim e (3 s) and in dissimilar joints post-weld heat treated at 450 degrees C for 3.6 ks. It is suggested that the intermetallic layer comprised a mix of tau-Al (Ti2Mg3Al18), Mg2Al3, and Al-3 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 Al friction welds.