FILLET 용접시편의 일축인장 및 굽힘 피로수명과 용접부 피로파단시 스트레인 변화 연구

초록

This study investigates the fatigue lives of SM490A material(base metal) specimens and fillet weld specimens, which are made same material and weld method for the railway vehicle, during the tensile and bending fatigue test. These fatigue lives have a difference, the fatigue lives of weld specimen are shorter than those of base metal. We measured the strains on the weld positions of the specimens during the fatigue test for investigation of crack initiation and crack growth. In these result, we could find the information of the crack initiation position on weld bead and the history of crack growth. Also we knew that the fatigue crack initiation cycles and the changes of the strain which were affected the fractured surface roughness and morphology.