| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-rigidity Cr-No steel weld metal stable in fracture toughness and excellent in SR resistance, and a submerged arc welding method by which the weld metal can be obtained. <P>SOLUTION: The weld metal welded by the submerged arc welding method contains, by mass%, 0.05 to 0.15% of C, 0.10 to 0.25% of Si, 0.50 to 1.30% of Mn, 2.00 to 3.25% of Cr, 0.90 to 1.20% of Mo, 0.20 to 0.40% of V, 0.010 to 0.040% of Nb and 250 to 450 ppm of O, and also contains not larger than 0.040% of Al, not larger than 0.010% of P. not larger than 0.010% of the total amount of S, Sn, Sb and As, not larger than 1.0 ppm of the total amount of Bi and Pb, and the balance Fe with inevitable impurities. In an microorganism, a crystal particle whose particle area is not larger than 400 μm<SP POS="POST">2</SP>occupies not smaller than 70% of the whole of the crystal particle. <P>COPYRIGHT: (C)2012,JPO&INPIT |
