| 摘要 |
PURPOSE:To improve the impact toughness of a weld metal by incorporating a specific amt. of Bi in a composite wire for gas shielded arc welding contg. TiO2, an deoxidizing element and B as essential components and decreasing the content of N as far as possible. CONSTITUTION:A flux to be packed in a composite wire for welding is incorporated therein essentially with 2-10% TiO2 based on the total amt. of the flux, 1.5-6.0% a deoxidizing element such as Si, Mn, Al, Mg or the like, and further 1 or both of B and B2O3 so as to contain 0.001%<=B+0.1B2O3<= 0.03%. Bi is further incorporated at 0.001-0.5% in the flux or a sheath metal and the content of N in the sheath metal is limited to <=50ppm. The flux is used by kneading the same with an aq. soln. of water glass to decrease the fume to be generated during welding. The weld metal formed by using such composite wire has good slag removability and excellent impact toughness. |
