METHOD OF VERIFYING BRITTLE FRACTURING RESISTING PERFORMANCE OF HIGH HEAT INPUT BUTT-WELDED JOINT

摘要

A welded joint satisfying (a1) a ratio Hv(WM)/Hv(BM) of a hardness of a weld metal Hv(WM) and a hardness of a base metal Hv(BM) of less than 1.1 or (a2) a hardness of the weld metal Hv(WM) of 210 or less and satisfying a fracture toughness value Kc of a weld zone Kc of (b1) over 2000N/mm 1.5 or (b2) Kc‰¤Kq ( = à D �¢ Àa , where à D : design stress and a: assumed defect dimension), wherein a brittle fracture resistance characteristic (fracture toughness value Kc) is verified by confirming that the measured hardness value satisfies the above (a1) or (a2) and that the measured absorption energy vE satisfies a required vE and by using a predicted Kc value based on a transition temperature vTrs.