Fatigue and Corrosion Behaviour of Circular Welded Blanks in Shock Tower Applications

Circular welded tailored blanks have an interesting potential for the manufacturing of weight optimised shock towers. However, it is not clear how the circular weld seam will behave when the component is exposed to fatigue and corrosion effects as they occur during driving. Therefore, appropriate tests have been performed to supply data on both issues. Model components deep drawn from blanks having circular welded reinforcement were submitted to variable amplitude loading in a servo-hydraulic fatigue frame. No fatigue damage was observed on the circular weld seam. The fatigue endurance correlates with the component stiffness which is in turn influenced by the diameter of the circular weld seam. Several components were coated by an industrial painting process and subjected to a tough cyclic corrosion test. All circular welded components showed an excellent corrosion resistance even on the weld seam. Based on the information collected in these tests, recommendations for part design can be given.