Solid wire, and gas-shielded arc welding method using same

Abstract

A solid wire which is for use in gas-shielded arc welding that employs a shielding gas and which is for use in welding galvanized steel sheets. The solid wire contains C, Si, Mn, P, S, O, and Cr in respective given amounts relative to the total mass of the solid wire, the remainder comprising Fe and unavoidable impurities. The solid wire satisfies the relationships 1.0<=(Si mass%+Mn mass%) / {100(S mass%+O mass%)}<=4.0 and 0.50<=(Mn mass% / Si mass%)<=2.00. The shielding gas is an argon gas which contains 25-40% CO2 gas. Improvements in spattering inhibition and pore generation inhibition (performance of inhibiting the generation of pore defects such as pits or blow holes) and an excellent bead appearance are rendered possible.

Description

technical field [0001] The present invention relates to a solid welding wire for gas shielded arc welding and galvanized steel plate welding and a gas shielded arc welding method using the same. Background technique [0002] Galvanized steel sheets are relatively inexpensive and have excellent rust resistance, so they are used in various fields such as automobiles, construction / building materials, and electrical products. [0003] Here, for galvanized steel sheets, the amount of galvanized coating (adhesion amount) varies depending on the field of use, but no matter what the amount of coating is, in welding of galvanized steel sheets, generally Both use gas metal arc welding (GMAW) using a solid wire, and this type of welding is often used especially in the automotive field. [0004] Although the galvanized steel sheet has the above-mentioned advantages (cheapness, rust resistance), on the other hand, it is not so good in terms of weldability in gas metal arc welding using ...

AI Technical Summary

Problems solved by technology

[0019] The techniques of Patent Document 2 to Patent Document 5 all limit the composition of the welding wire, but only by limiting the composition, under severe welding conditions such as a downward posture where porosity defects and spatter frequently occur, the suppression of the occurrence of porosity defects and spatter cannot be fully exerted. The effect of reducing such

[0020] In addition, although the technology of Patent Document 1 limits the composition of the welding wire and the composition of the shielding gas, the effects of suppressing the occurrence of porosity defects and reducing spatter cannot be sufficiently exhibited in this combination.

Furthermore, in the technique of Patent Document 1, O is mixed in the shielding gas. 2 When the surface tension of the molten pool is excessively reduced, a large number of pore defects and splashes occur

[0021] That is, the techniques of Patent Document 1 to Patent Document 5 are insufficient in suppressing the occurrence of porosity defects and reducing spatter.

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