Fatigue assessment of a welded automotive differential under multiaxial and variable amplitude loading

The fatigue assessment of two weld seams in a differential is performed based on notch stresses at the weld root with a reference radius of rref = 0.05mm. During one revolution of the differential local shear and normal stresses change non-proportionally. For the assessment, a load spectrum that approximates the service loads is considered. The local multiaxial loading conditions are assessed with the modified Gough-Pollard hypothesis using a comparison value of CV = 0.5 and the variable amplitude loading is assessed with a linear damage accumulation. The assessment results are compared to the outcome of a validation test with the component.