Fatigue behaviour of automatically HFMI-treated welds

Abstract

Abstract Due to notches, welds are most critical regarding fatigue failure within cyclic loaded constructions. Therefore, various post-weld-treatment techniques like post weld treatment by High Frequency Mechanical Impact Treatment (HFMI) have been invented to improve the fatigue strength of welded details. The benefit, resulting of HFMI-treatment has already been proven by numerous studies. Since a manual HFMI-treatment must be performed by a skilled and trained person to ensure an acceptable treatment-quality, an automated application of HFMI-treatment is supposed to result in a more reliable and consistent treatment result, which doesn’t depend on the operator. Furthermore, a robotic application of HFMI-treatment enables an economic implementation of HFMI-treatment of automated welded constructions like offshore wind-energy converters and various mechanical components, as these parts don’t have to been taken out of the production chain to manually perform HFMI-treatment. This paper focuses on the experimental investigation of the fatigue behaviour of automated HFMI-treated welds, using a developed robotic application of the HiFIT device (specific HFMI-tool).