MTT and LTT Weld Metal for Reduction of Stress Concentration and Tensile Residual Stress of Cruciform Welded Joint

摘要

Stress concentration and tensile residual stress are detrimental to fatiguelife of welded joints. In order to reduce stress concentration, amathematical design method of tensile triangles (MTT) based on bionicswas applied to weld shape design. Accordingly, the stress concentrationof elongated weld bead with MTT design was computed using in-houseFEM software JWRIAN. Furthermore, the elongated weld bead withMTT design utilized the low-transformation-temperature (LTT) weldmetal to reduce tensile residual stress. It was found that combination ofMTT and LTT weld metal was beneficial to reduction of stressconcentration and tensile residual stress of cruciform welded joint.