| 摘要 |
PURPOSE:To prevent the generation of low temp. cracking in the weld heat affected zone in the stage of welding steel material of high carbon equiv., by incorporating a specific small amt. of Zn powder in a flux for welding. CONSTITUTION:In the stage of welding steel material of high carbon equiv. having high strength and high toughness, 0.5-2.0wt% Zn powder is incorporated in a coating flux of a welding electrode for submerged arc welding or in the flux contained in a composite wire for submerged arc welding. Zn of a low m.p. is evaporated by the effect of the high temp. of the arc in the stage of welding, and the partial pressure of H2 in the arc atmosphere is decreased, whereby the amt. of the diffusible hydrogen in the weld metal is decreased without giving any adverse influence on the arc, and the low temp. cracking resistance in the weld heat affected zone by the hydrogen is improved. |
