Friction welding of aluminum alloys to copper was carried out. Under the different friction pressure based on the hardness and the heat conductivity of each joining aluminum alloys, a relationship between the friction torque and the joint performance was examined. The friction torque of A2011, A2017, A2024 and A7075 to copper decreased showing a even torque curve with an increase in friction time and showed poor-friction weldability. On the other hand, in the case of A1050, A5052, A5056, A6061 and A6063 to copper, the friction torque remained high showing a rough torque curve and showed good-friction weldability.
Friction welding has been widely used for welding of similar and dissimilar materials. However, relationships between welding parameters and mechanical and physical properties of welding materials are still not understood. So, in order to reveal these relationships, we have been studied on the basic friction welding mechanism such as influence of friction heat input and friction torque on friction weldability. Our previous study has revealed that the heat input during friction welding controls joint strength of weld joints (Sawai et al., 1997). In this study, friction welding of aluminum alloy to copper which is seemed to be one of a pair of low-weldability material because of formation of brittle intermetallic compounds was carried out, and suitable welding conditions for producing a sound weld were investigated.
The materials used in this study were 1050-H14, 2011-T3, 2017-T4, 2024-T4, 5052-H34, 5056-H34, 606 l-T6, 6063-T5 and 7075-T6 aluminum alloys to industrial pure copper. The chemical compositions and properties of base materials are shown in Table 1 and 2. These materials were supplied as drown bars of 16ram in diameter, and machined to welding materials of 14mm in diameter of a friction surface as shown in Fig.1.
