Fatigue strength distribution and probabilistic evaluation on stainless steel welded components under mixed mode loading

Plane sheet specimens and their welded components were examined through fatigue tests, and the data were evaluated by the base line regression model. The three-parameter Weibull estimations showed the most accurate approximation of the measured values with the median rank treatment. The fatigue strengths, limits, lives and failure probabilities under different loading conditions became predictable. The fatigue strengths and limits under mixed mode loading were compared with the Gough?Pollard relation, and could be predicted from the load ratio of the torsion to bending. The notch factors of welded components were 1.24?2.55 at the load ratio of 0.31. The fatigue strengths and scatters mainly depended on the weld flank angle, and had excellent agreement with the weld shape parameter which included the influence of the weld toe radius. They varied with the material factor which included the influences of the non-uniform microstructure, weld imperfection, etc.

Automated summary

Through fatigue tests and data evaluation, fatigue strengths, limits, lives, and failure probabilities under different loading conditions can be predicted. The notch factors, fatigue strengths, and scatters of welded components mainly depend on the weld flank angle and material factors.