Fatigue strength of hot-dip galvanized S960 cut edges and longitudinal welds

Experimental fatigue test series were conducted for component sized hot-dip galvanized (HDG) S960 cut edges and longitudinal welds. Scanning electron microscopy (SEM) was used to identify and characterize the crack initiation location and the effects of local chemical composition. Micro-scale liquid metal embrittlement in the vicinity of the cut surface was found to slightly reduce fatigue performance of tested laser cut, machined and welded specimens. The use of ultra-high-strength steels in the HDG condition is discussed and fatigue strength guidelines are proposed for the tested details.