Fatigue strength evaluation of 5059 aluminum alloy welded joints Considering welding deformation and residual stress

With the transformation and upgrading of shipbuilding industry, aluminum alloy shipbuilding will gradually develop towards energy saving, light weight and environmental protection. As a new generation of trustworthy aluminum alloy structure, 5059 aluminum alloy material has better mechanical properties and corrosion resistance. However, two prominent shortcomings of aluminum alloy welding structure are large welding deformation and low fatigue strength. In order to accurately consider the influence of welding defects, the temperature field simulation program of thin plate welding structure is designed to predict the welding deformation and residual stress. The simulation results of temperature field and welding deformation of typical welded joints are in good agreement with the test results. Moreover, taking welding deformation and residual stress as initial conditions, the fatigue strength class curves of 5059 aluminum alloy welded joints are renewed based on the hot spot stress.

Automated summary

With the transformation and upgrading of the shipbuilding industry, aluminum alloy shipbuilding is developing towards energy saving, lightweight, and environmental protection. However, the welding of aluminum alloy structures has two prominent shortcomings: large deformation and low fatigue strength. This study aims to accurately consider the influence of welding defects by designing a temperature field simulation program for thin plate welding structures to predict welding deformation and residual stress. The simulation results show good agreement with the test results for the temperature field and welding deformation of typical welded joints. Furthermore, the fatigue strength classification curves of 5059 aluminum alloy welded joints are updated based on the hot spot stress using welding deformation and residual stress as initial conditions.