Friction Stir Welding of Aluminum Alloy AA2024-T351 with OFHC Copper

Prof. Dr. Adnan Naama Abood, Prof. Dr. Moneer Hameed Tolephih, Asst. Lect. Hayder Ibrahim Kadhum

The effect of Friction Stir Welding (FSW) parameters on microstructure and mechanical properties of Al/Cu was investigated. Three rotational speeds have experienced (500 rpm, 850 rpm and 1660 rpm) with varying travel speeds. The tool pin was shifting from the interface of the weldments with three pin offset (1, 1.5 and 2mm). The results indicated that maximum mechanical properties can be attained at 850 rpm, 65 mm/min with pin offset of 1.5 mm on aluminum side. Tensile strength of dissimilar weldment was approximatly 80 % of that of Oxygen Free High Conductivity copper, while, maximum hardness value was observed at nugget zone. High interaction between the base metals was found at nugget zone, which is consisted mainly of lamellar and particular configurations of base metals and Intermetallic Compounds (IMCs) dispersed in Al matrix, while other FSW parameters have devastating weldments defects due to inappropriate interaction between base metals and negative effects of IMCs. IMCs were consisted of AlCu , AlCu and AlCu