| 摘要 |
Basic bonded fluxes for submerged arc welding consisting of a mixture of a slag forming composition, a gas forming composition and metal powders, in which a volume contraction of the weld slag is remarkable in the cooling process after the solidification of the weld slag and the removal of slag in the groove is easy, contain 5 to 20% by weight of BaO, not more than 10% by weight of CaO, 20 to 50% by weight of MgO, 6 to 25% by weight of SiO2, 3 to 15% by weight of Al2O3 and 7 to 18% by weight of CaF2 as the slag forming composition, a value of basicity shown by a ratio of the basic component and the acidic component being 2.3 to 4.5, the above described contents of BaO, CaO and MgO including amounts corresponding to the values obtained by calculating an amount of carbonates of these metals which are incorporated as the gas forming composition, as oxides and further contain 10 to 60% by weight of metal carbonates as the gas forming composition. |
