36 巻 (2018) 1 号 p. 68-76
Submerged arc welding (SAW) is widely used in heavy industry fields, such as ship buildings or steel pipe mills. Some papers pointed out that recycle use SAW slag to SAW flux is effective to conserve natural resources and also to save flux cost. In this paper, we have investigated reasons why M. Fe content of slag changed when different chemical composition flux was conducted in SAW. We have also investigated which one either welding wires or base metal plates are main source of M. steel particles in SAW slag. We have concluded that change of M. Fe content in slag resulted from difference of arc temperature in SAW, and welding wires were main source of fine M. steel particles in SAW slag.