| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a bonded flux and a solid wire for submerged arc welding, each of which gives a weld part (weld metal) having excellent low-temperature fracture toughness with superior weldability, and to provide a method for subnerged arc welding of a steel for low temperature service. <P>SOLUTION: The bonded flux includes, by mass, 23-43% MgO, 11-31% Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>, 6-16% CaF<SB POS="POST">2</SB>, 7-20% SiO<SB POS="POST">2</SB>, 1.0-8.0% metal carbonates in terms of CO<SB POS="POST">2</SB>, 2-16% at least one of CaO and BaO, 0.4-1.5% Si, 1.0-7.0% Ti and oxide thereof in total in terms of Ti, 0.01-0.20% at least one of B and oxide thereof in total in terms of B, and 1.0-6.0% oxides of alkali metals, Na, K and Li in total in terms of respective elements, and (Ti corresponding value+B corresponding value)/SiO<SB POS="POST">2</SB>satisfies 0.05 to 0.55. <P>COPYRIGHT: (C)2012,JPO&INPIT |
