| 摘要 |
PROBLEM TO BE SOLVED: To provide a thick steel plate for welded structures which has excel lent fatigue strength of a welded joint, and to provide a production method therefor. SOLUTION: The thick steel plate for welded structures having excellent fatigue strength of a welded joint has a composition containing, by mass, 0.015 to 0.15% C, 0.01 to 2% Si, 0.2 to 1.5% Mn, <=0.03% P, <=0.01% S and >0.1 to 1% Al, and the balance Fe with inevitable impurities, and satisfying Ceq<=0.24+0.03×√Al (Si: <1%) or Ceq<=0.275+0.03×√Al (Si; >=1%), wherein, Ceq=C+Mn/6+(Cu+Ni)/15+(Cr+Mo+V)/5+Nb/3.
|
