A MATHEMATICAL-MODEL TO PREDICT FATIGUE NOTCH FACTOR OF BUTT JOINTS

A mathematical model is developed to predict the fatigue notch factor of butt welds subject to number of parameters such as weld geometry, r esidual stresses under dynamic combined loading conditions (tensile an d bending). Linear elastic fracture mechanics, finite element analysis , dimensional analysis and superposition approaches are used for the m odelling. The predicted results are in good agreement with the availab le experimental data. As a result, scatters of the fatigue data can be significantly reduced by plotting S-N curve as (S . K-f) vs. N.