| 摘要 |
PURPOSE:To obtain a high strength weld metal which is highly tough and embrittlement less during use by performing submerged arc welding by a Cr-Mo low alloy steel wire contg. C, Si and Mn and further contg. >=1 kind among V, Nb and Ti and contg. N and a highly basic flux. CONSTITUTION:This low alloy steel wire contains the following compsn.: The wire contains 0.07-0.17% C, <0.20% Si, 0.40%<=Mn <1.10%, 1.8-3.5% Cr and 0.8-1.2% Mo and contains further >=1 kind among<0.1% V, <0.06% Nb and <0.30% Ti and contains 0.02-0.15% V+2Nb+0.3Ti and 0.0080-0.0180% N. Otherwise the wire contains further 0.001-0.015% B according to need. Such low alloy steel wire and a highly basic welding flux having >=1.40 basicity (wt%) shown in the formula are combined according to need and submerged arc welding of base metals, particularly extremely thick plates of a Cr-Mo steel is performed. The resultant weld metal has excellent toughness and strength even a fter long-time stress relief annealing and embrittlement extremely less during use. |
