Abstract: In the bonding of an aluminum alloy material (11) to a steel material (12) by TIG welding, a tungsten electrode (1) which has a tip having a diagonally cut tip face (2) and asymmetrical to the electrode center axis (6) is used. The tungsten electrode (1) is oriented toward the welding line from the upper side of the aluminum alloy material (11) in such a manner that the tip face side of the tungsten electrode (1) faces the aluminum alloy material (11) side and the tip (2a) of the tip face (2) faces the steel material (12) side. In this manner, an arc (3) from the tip (2a) is directed to the steel material (12) side.

Abstract: In the bonding of an aluminum alloy material (11) to a steel material (12) by TIG welding, a tungsten electrode (1) which has a tip having a diagonally cut tip face (2) and asymmetrical to the electrode center axis (6) is used. The tungsten electrode (1) is oriented toward the welding line from the upper side of the aluminum alloy material (11) in such a manner that the tip face side of the tungsten electrode (1) faces the aluminum alloy material (11) side and the tip (2a) of the tip face (2) faces the steel material (12) side. In this manner, an arc (3) from the tip (2a) is directed to the steel material (12) side.

Abstract: Disclosed are: a dissimilar material weld joint being formed by joining an iron type material and an aluminum type material and having not only a high strength but also an excellent ductility; and a weld joining method allowing such a joint to be stably produced. A dissimilar material weld joint 1 formed by joining an iron type material 2 and an aluminum type material 3, wherein: voids 4a are formed beforehand on the side of said iron type material 2 at a predetermined interval along a weld line 6; both said iron type and aluminum type materials are weld joined so that said voids 4a are filled with molten aluminum 7; and the minimum value of the ratio (L-Al)/(L-Fe) of the length (L-Al) of an aluminum type welding material 10 with which said voids 4a are filled to the length (L-Fe) of said iron type material 2 adjacent to said voids 4a filled with said aluminum type welding material 10 along said weld line 6 on the section containing said weld line 6 is in the range from 0.

Abstract: Disclosed are: a dissimilar material weld joint being formed by joining an iron type material and an aluminum type material and having not only a high strength but also an excellent ductility; and a weld joining method allowing such a joint to be stably produced. A dissimilar material weld joint 1 formed by joining an iron type material 2 and an aluminum type material 3, wherein: voids 4a are formed beforehand on the side of said iron type material 2 at a predetermined interval along a weld line 6; both said iron type and aluminum type materials are weld joined so that said voids 4a are filled with molten aluminum 7; and the minimum value of the ratio (L-Al)/(L-Fe) of the length (L-Al) of an aluminum type welding material 10 with which said voids 4a are filled to the length (L-Fe) of said iron type material 2 adjacent to said voids 4a filled with said aluminum type welding material 10 along said weld line 6 on the section containing said weld line 6 is in the range from 0.

Abstract: There is provided a laser welded joint structure for a flare groove joint, wherein a flat portion 4 for forming a square-like groove in the flare groove is formed at a beam-injected portion of the flare groove on at least one side of welded members 1 and 2. There is also provided a gas generator comprising the above-described laser welded joint structure.

Abstract: Disclosed herein is a filler metal for joining (mainly by high energy density beam welding) a part of porous sintered material to a part of the same material or steel, which gives rise to a weld zone free of such defects as cold cracking and blowholes.The filler metal contains, by weight, at least one selected from the group consisting of Cr, Mo, and Si and at least one selected from the group consisting of Ni, C, and Mn in an amount specified by the equations belowY .gtoreq.-(1/3)X +23 and Y .gtoreq.12whereX =Cr(%) +Mo(%) +1.5 Si(%)Y =1.2 Ni(%) +20 C(%) +0.8 Mn(%)and at least one selected from the group consisting of Al, Ti, Zr, and V in a total amount of 0.3-5%, with the balance being Fe and inevitable impurities. The filler metal may be in the form of solid wire or cored wire. The filler metal for arc welding has a composition defined by Y .gtoreq.-(1/3)X +18 and Y .gtoreq.7.