| 摘要 |
PURPOSE:To provide a titled fused flux which forms a weld zone having high toughness and excellent resistance to hydrogen cracking by using a specific ratio each of Al2O3, SiO2, CaO, CaF2 and TiO2 as essential components and specifying the basicity thereof. CONSTITUTION:The flux contg., by weight %, 30-45% Al2O3, 3-10% SiO2, 15-30% CaO, 10-25% CaF2 and 3-12% TiO2 as the essential components and having the basicity BL expressed by the formula within a 1.40-2.95 range is prepd. The respective components expressed by the suffices in the formula are represented by (i) and the molar fraction of the (i) component is expressed by Ni. Ncao calculates the included BL by converting CaF2 as well to CaO. The fused flux for submerged arc welding with which the quantity of diffusible hydrogen is as low as <=1.5cc/100g and the quantity of the oxygen in molten metal is about <=250ppm is thus obtd. |
