| In the absence of standardized specimen geometry for fatigue testing of butt welded joints, the first phase of this research focused on the determination of the geometry of a representative test specimen. Base metal specimens (quenched and tempered AISI 410 steel), aligned welded joints, misaligned welded joints and joints with angular misalignment were tested for two thicknesses, 1 mm and 3 mm. The number of specimens was determined to have at least six representative fractures at each misalignment level and each thickness.;The last phase of the research deals with the improvement of the fatigue strength of welded joints by cold roll planishing along the weld bead. To emphasize the effect of this method, welded joints have been manufactured by the same process as that of "as welded" specimens, but with additional operations of annealing and roll planishing. The results of the fatigue testing show the improvement of the fatigue strength of aligned, misaligned and angular misaligned welded joints. The fatigue strength improvement of aligned welded joints is the result of the elimination of the weld geometry. The fatigue strength improvement of misaligned welded joints is the result of the simultaneous elimination of the misalignments and the weld geometry. The roll planishing process brings the fatigue strength of aligned and misaligned welded joints to approximately the same level as that of base metal. (Abstract shortened by UMI.)... |
