Provided is an austenitic stainless steel weld joint that is excellent in polythionic acid SCC resistance and naphthenic acid corrosion resistance, and is also excellent in creep ductility. An austenitic stainless steel weld joint includes a base material and a weld metal. The weld metal has a chemical composition at its width-center position and at its thickness-center position consisting of, in mass %, C: 0.050% or less, Si: 0.01 to 1.00%, Mn: 0.01 to 3.00%, P: 0.030% or less, S: 0.015% or less, Cr: 15.0 to 25.0%, Ni: 20.0 to 70.0%, Mo: 1.30 to 10.00%, Nb: 0.05 to 3.00%, N: 0.150% or less, and B: 0.0050% or less, with the balance: Fe and impurities.

Provided is an austenitic stainless steel weld joint that is excellent in polythionic acid SCC resistance and naphthenic acid corrosion resistance, and is also excellent in creep ductility. An austenitic stainless steel weld joint includes a base material and a weld metal. The weld metal has a chemical composition at its width-center position and at its thickness-center position consisting of, in mass %, C: 0.050% or less, Si: 0.01 to 1.00%, Mn: 0.01 to 3.00%, P: 0.030% or less, S: 0.015% or less, Cr: 15.0 to 25.0%, Ni: 20.0 to 70.0%, Mo: 1.30 to 10.00%, Nb: 0.05 to 3.00%, N: 0.150% or less, and B: 0.0050% or less, with the balance: Fe and impurities.

A manufacturing method for a joint part in which a first metal piece and a second metal piece are joined to each other by performing welding by irradiating a high-energy beam to a joint surface on which the first metal piece and the second metal piece face each other, the first metal piece including a first flow path for passage of a fluid provided at a specific depth from a surface on a side exposed to the high-energy beam, the second metal piece including a second flow path for passage of the fluid provided at a specific depth from the surface on the side exposed to the high-energy beam, and the first flow path and the second flow path being coupled to each other on the joint surface.

A manufacturing method for a joint part in which a first metal piece and a second metal piece are joined to each other by performing welding by irradiating a high-energy beam to a joint surface on which the first metal piece and the second metal piece face each other, the first metal piece including a first flow path for passage of a fluid provided at a specific depth from a surface on a side exposed to the high-energy beam, the second metal piece including a second flow path for passage of the fluid provided at a specific depth from the surface on the side exposed to the high-energy beam, and the first flow path and the second flow path being coupled to each other on the joint surface.

A laser welded joint has weld metal provided between a plurality of steel sheets. A chemical composition of the weld metal has predetermined components, and average hardness of the weld metal is 350 to 540 in Vickers hardness. In the weld metal, distribution density of porosities having a diameter of 2 μm to 50 μm is equal to or less than 5.0 pieces/mm.sup.2. In the weld metal, distribution density of oxide inclusions having a diameter of 3 μm or more is 0.1 to 8.0 pieces/mm.sup.2.

A laser welded joint has weld metal provided between a plurality of steel sheets. A chemical composition of the weld metal has predetermined components, and average hardness of the weld metal is 350 to 540 in Vickers hardness. In the weld metal, distribution density of porosities having a diameter of 2 μm to 50 μm is equal to or less than 5.0 pieces/mm.sup.2. In the weld metal, distribution density of oxide inclusions having a diameter of 3 μm or more is 0.1 to 8.0 pieces/mm.sup.2.

A different material joining structure has: a first panel made of a first metal material; a second panel made of a second metal material that has a higher conductivity than that of the first panel, is different from the first metal material, and at least a part of which faces the first panel; and a rivet for joining the first panel and the second panel, wherein the rivet is made of the first material, and includes a head portion that is embedded in the second panel in a non-penetrating manner and a bottom portion that abuts on the first panel, and wherein a nugget portion as a joint portion is disposed between the first panel and the bottom portion, the nugget portion being formed by resistance welding the rivet to the first portion with the rivet disposed between the first panel and the second panel.

A connection part having a body portion and a connection surface being arranged on the body portion. The connection surface is configured for being connected to a mating part. Moreover, the connection part has at least one positioning protrusion being located at a distance (d) away from an edge of the connection surface and being movably connected to the body portion. In a pre-assembly position, the positioning protrusion at least partially protrudes with respect to the connection surface. In an assembly position, the positioning protrusion is flush with the connection surface or is retracted with respect to the connection surface. Furthermore, a part connection including such a connection part and a mating part is presented. Additionally, a method for adhesively connecting a connection part and a mating part is explained.

A connection part having a body portion and a connection surface being arranged on the body portion. The connection surface is configured for being connected to a mating part. Moreover, the connection part has at least one positioning protrusion being located at a distance (d) away from an edge of the connection surface and being movably connected to the body portion. In a pre-assembly position, the positioning protrusion at least partially protrudes with respect to the connection surface. In an assembly position, the positioning protrusion is flush with the connection surface or is retracted with respect to the connection surface. Furthermore, a part connection including such a connection part and a mating part is presented. Additionally, a method for adhesively connecting a connection part and a mating part is explained.

An enclosed heat sink with a side wall structure is provided. The side wall structure includes a welding body having a first welding plane and a side wall structure having a second welding plane. The first welding plane and the second welding plane are pressured and welded to each other, such that the welding body and the side wall structure encapsulate a cavity. A width of the second welding plane is smaller than a width between two side surfaces of the side wall structure.