Experimental investigation on the fatigue strength assessment of welded joints made of S1100 ultra-high-strength steel in as-welded and post-weld treated condition

摘要

In this paper, a fatigue test program including 24 tested specimens made of S1100 steel was carried out to investigate the fatigue performance of the ultra-high-strength steel (UHSS) welded joints in the as-welded (AW) and post-weld treated (PWT) condition. Fatigue strength was assessed using the conventional stress-based methods, i.e. nominal stress, structural hot spot (HS) stress and effective notch stress (ENS) approaches, and using a novel multi-parametric fatigue design approach, named as the 4R method. The results showed a good correspondence between the experimental results and computed fatigue lives when using the 4R method. The conventional methods showed conservative results in R = 0.1 loading, and unconservative results in R = 0.5 loading, respectively.