INFLUENCE OF RESIDUAL STRESS REDUCTION BY LOCAL HEATING ON FATIGUE RESISTANCE OF FILLET BOX WELDED JOINTS

Abstract

 A series of analysis and experiments were carried out to investigate the influence of residual stress reduction by local heating on the fatigue resistance of fillet box welded joints. The numerical analysis was conducted assuming the condition in which various magnitudes of tensile and compressive stresses were applied to the weld toe in the fatigue experiments on box welded joints with/without local heating for residual stress reduction. It was suggested that the improvement of fatigue resistance due to residual stress reduction may be greater when compressive stress is applied than when tensile stress is applied to the weld toe. The fatigue life of the locally heated joints was 4.9 – 10 times longer than that of the as weld joints in the stress range of 100 N/mm² by compressive cyclic loads.