| 摘要 |
PURPOSE:To obtain easily a composite oxide having excellent quality as a raw material to be compounded in producing a flux for welding by heating and baking a mixture composed of the powder and granules of metallic carbonate and the powder and granules of metallic oxide at a temp. of the m. p. or below in an oxidizing atmosphere. CONSTITUTION:The powder and granules of metallic carbonate such as SrCO3, BaCO3 or the like and the powder and granules of metallic oxide such as Fe2O3 or the like are mixed in such a way that the molar ratio of the metallic oxide/ metallic carbonate attains about >=1. The mixture is heated and baked at a suitable temp. below the m. p. in an oxidizing atmosphere and the composite oxide contg. about <=5wt% CO2 after the baking is obtd. The composite oxide having high quality is produced with the simple operation at a high yield with good productivity by the above-mentioned method. If such composite oxide is compounded in a flux for welding, the satisfactory result is obtd. in the mechanical property, paintability, resistance to dry cracking, welding operability, etc. in the weld zone of a mild steel, etc. |
