| Light-weight design in structure is a key development of advanced aeronautic manufactural technologies. Combining superplastic forming with diffusion bonding technology is able to manufacture complex structure with light weight and good holistic performance. Superplastic forming/diffusion bonding (SPF/DB) of titanium alloy has shown great technical and economic benefits. However, the research and applications of SPF/DB technology of aluminum alloy are limited, because DB process is difficult to be implemented. Applying superplastic forming/friction stir welding (FSW) instead of SPF/DB to form multilayer components is of great value in research and development prospect due to feasible theory and great economic benefit.In this thesis, relevant theories in superplastic forming and friction stir welding were firstly discussed. Then mechanical behavior of 5083 aluminum alloy under superplastic deformation was studied through uniaxial tension tests. The optimal superplastic parameters of 5083 aluminum alloy were obtained, in which optimal temperature is 525℃, optimal strain rate is 2.0×10-4s-1 and strain rate sensitivity index m value is 0.519. In addition, numerical simulation for FSW/SPF process of typical three-layer structure was carried out on MARC software. Thickness distribution was predicted and optimal pressure-time curve was generated with the maximum constant strain rate control.On the basis of finite element simulation, FSW/SPF process of aluminum alloy was investigated. Furthermore, friction stir welding process was analyzed in detail and experiment on FSW/SPF was conducted. At last, some possible problems of FSW/SPF were put forward.
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