Fatigue assessment of welded and high frequency mechanical impact (HFMI) treated joints by master notch stress approach

To proof the applicability, a comprehensive validation of the HFMI master notch stress approach incorporating over 230 additional steel joint specimen results covering both constant and variable amplitude tests is conducted. The constant amplitude study reveals that the fatigue strength of the HFMI master notch stress approach, utilizing the notch factor KW, is well applicable for material strengths up to ultra high-strength steels with a nominal yield limit of 1300 MPa. In addition, the notch stress based service strength evaluation of variable amplitude loaded HFMI-treated high-strength steel joints considering a specified damage sum of D = 0.3 according to Sonsino can be also well utilized for HFMI-treated joints.