| 摘要 |
PURPOSE:To obtain a weld zone with less pits by using a solid wire of the Fe having a specified chemical composition as a positive electrode, transferring the globule to the base metal when a base current is applied, and carrying out welding in a shielding gas of Ar mixed with specified amts. of CO2 or O2. CONSTITUTION:The solid wire consisting, by weight, of 0.02-0.12% C, 0.10-0.80% Si, 0.20-1.20% Mn, 0.003-0.03% P, 0.003-0.03% S, and the balance Fe is used, and a shielding gas consisting essentially of Ar and contg., by volume, 5-50% CO2 or 2-20% O2 is used. A periodically repeated pulse DC current is projected on the zinc plating layer 7 by the heavy-current arc column 3 when a peak current is applied to melt and vaporize the layer 7, the globule 4 is short-circuited and transferred to the base metal from the tip of the solid wire 2 when a base current is applied and welding is carried out. By this method, pits are not generated, a welded metal part with an extremely small number of blowholes is obtained, the strength of a structure is not decreased, and the appearance is also ameliorated. |
