The fatigue behaviors of butt welds ground flush in the super-long life regime

Abstract The fatigue properties of EH36 steel and butt welds ground flush in the super-long life regime were studied in this paper. Experimental results indicate that fatigue fracture may still occur during 10 8 –10 10  cycles, which is incompatible with conventional method of using the fatigue strength corresponding to 1 × 10 7  cycles to design welding structure serving in the super-long life regime. Scanning electron microscope analysis shows that fatigue crack mainly initiates from internal defects in the fusion face for butt welds ground flush. A new kind of “fish-eye” is found in welded joints. The relation between fatigue life and area of defects in the butt welds ground flush is confirmed.

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