Patent ID: 9339887
Filing Date: 2016-05-17
CPC Classification: B23K

Claim Text:
1. A method for bonding dissimilar metals to each other, comprising: overlaying at least a part of an aluminum alloy material on a steel material; and fillet welding the aluminum alloy material and the steel material by direct current tungsten inert gas (DC TIG) welding using a tungsten electrode while feeding a flux-cored wire to a step section formed by an end of the aluminum alloy material and a surface of the steel material with an aluminum alloy material side being made a positive pole, wherein the tungsten electrode comprises a tip of a shape asymmetric with respect to an axis of the tungsten electrode, the tip comprises a tip surface shaped at an angle of 20° or more and 40° or less relative to the axis, and during said fillet welding, an arc generated from the tip of the tungsten electrode is directed to a steel material side by directing the tungsten electrode to a welding line from an upper side of the aluminum alloy material so that the tip of the tungsten electrode is directed to the steel material side and that the tip surface is directed to the aluminum alloy material side.