2018 年 36 巻 3 号 p. 167-174
Submerged arc welding (SAW) is widely used in the fields such as ship buildings and steel pipe production. Recently reuse of SAW slag as a raw material of SAW flux has been discussed, as a measure to reduce costs and to conserve natural resources. The present study investigated distribution of P in the slag and its major origin (i.e., welding wire or base metal plate). It also proposed slag remelting as a method of P concentration reduction of the slag. It was recognized that P was mainly distributed in the matrix and metallic steel particles with only larger diameters. It was also identified that the base metal plate was the main source of P in the slag. Remelting of the slag was proved as a promising method for P concentration reduction of the slag.