Joint structure

Abstract

A joint structure includes a first metallic material having a first projection, a second metallic material similar to and weldable to the first metallic material, and a different material having a first penetrating part and sandwiched between the first and second metallic materials, the different material being difficult to weld to the first and second metallic materials. The first projection is smaller than the first penetrating part and is spaced from the rim of the first penetrating part. The first projection is positioned in the first penetrating part and spaced from the second metallic material by a gap. The gap has a size of a predetermined percentage of the thickness of the first projection to which arc welding is applied. The first and second metallic materials are melted and joined together inside the first penetrating part to compress and fix the different material, so all three are fixed together.

1 - 8 . (canceled) 
     
     
         9 . A welding method for forming a joint structure having a first metallic material and a second metallic material weldable to the first metallic material that sandwich a different type of material that is difficult to weld to the first metallic material and the second metallic material, the first metallic material and the second metallic material being welded together, and the different type of material and the first and second metallic material being fixed together, the welding method comprising:
 the different type of material has a first penetrating part,   applying arc to a part of the first metallic material or a part of the second metallic material at a position corresponding to a position of the first penetrating part of the different type of material in a thickness direction to weld together the first metallic material and the second metallic material and fix together the different type of material and the first and second metallic materials, wherein   the first metallic material and the second metallic material are arranged so as to sandwich the different type of material, and   at least one of the first metallic material and the second metallic material sandwiching the different type of material has an discharge opening penetrating in the thickness direction, the discharge opening being located at a position outside of the first penetrating part.   
     
     
         10 . The welding method according to  claim 9 , wherein
 the first metallic material has a second penetrating part,   the first metal material having the second penetrating part is located on the different type of material so that the position of the first penetrating part corresponds to a position of the second penetrating part in the thickness direction.   
     
     
         11 . The welding method according to  claim 10 , wherein the second penetrating part is smaller in diameter or width than the first penetrating part. 
     
     
         12 . The welding method according to  claim 9 , wherein the arc is applied by using one of following types of welding:
 arc welding with a consumable electrode;   tungsten-inert-gas welding with a non-consumable electrode; and   plasma welding with a non-consumable electrode.   
     
     
         13 . The welding method according to  claim 9 , wherein after the sandwiching of the different type of material with the first metallic material and the second metallic material, a second gap is present between the first metallic material and the second metallic material that physically separates the first metallic material from the second metallic material in the thickness direction, the second gap being located at a position corresponding to the position of the first penetrating part of the different type of material and having a size of a predetermined percentage of a thickness of the part of the first metallic material or the part of the second metallic material to which the arc is applied. 
     
     
         14 . The welding method according to  claim 9 , wherein the applying of the arc occurs while the second gap is present between the first metallic material and the second metallic material.