A multilayer flat steel product may include a multitude of mutually bonded steel alloy layers. A steel of a first steel alloy may be provided in at least one of the steel alloy layers, and a steel of a second steel alloy different than the first steel alloy may be provided in at least one of the other steel alloy layers. The steel of the first steel alloy may have high strength, and the steel of the second steel alloy may have lower strength and lower carbon content. To enable function-optimized modelling of local material properties in all directions, at least one steel of the first steel alloy and at least one steel of the second steel alloy may be present at least within one layer of the flat steel product. Further, a component, such as for a motor vehicle body, may be comprised of a corresponding flat steel product.

A joint unit includes a first metal pipe, a second metal pipe, and a joint portion (a region including a joint interface at which the end faces of the first and second metal pipes are joined to each other. At the joint portion, an outer circumferential bead portion protruding toward the outer circumference side and an inner circumferential bead portion protruding toward the inner circumference side are formed. The difference between the width of the outer circumferential bead portion (the width L1 of a grinding portion and the width L2 of the inner circumferential bead portion in a direction from the first metal pipe toward the second metal pipe is equal to or smaller than 40% with respect to the average value of the width L1 of the outer circumferential bead portion and the width L2 of the inner circumferential bead portion.

A method of eliminating dissimilar metal welds has been disclosed. The method includes the steps of providing a first part having a first alloy composition; providing a second part having a second alloy composition different from the first part; connecting a containment structure to the first part; pouring a powder into the containment structure such that the powder is in contact with the first part; positioning a portion of the second part in the containment structure such that the second part compresses the powder between the first and second parts; and performing hot isostatic pressing (HIP) to consolidate the powder and join the first and second parts together.

A method and assembly for preventing corrosion between two work pieces. At least a portion of a neck portion of a second end portion of an end piece is disposed within a hollow portion in a first end portion of a drive shaft tube. The inner surface of the first end portion of the drive shaft tube is magnetic pulse welded to a first tapered portion of the neck portion of the end piece. A coating and a sacrificial material is applied over an interface between an end surface of said first end portion of said drive shaft and said end piece defining a gap. The coating and sacrificial material is then leveled and a shrink-wrap material is disposed radially outboard from the gap. Finally, heat is applied to the shrink-wrap material sealing said gap.

This foil for a secondary battery negative electrode collector (negative electrode-collecting foil 5b) includes a first Cu layer (51) made of Cu or a Cu-based alloy, a stainless steel layer (52), and a second Cu layer (53) made of Cu or a Cu-based alloy, which are disposed in this order, a total thickness is 200 μm or less, and 0.01% proof stress is 500 MPa or more.

This foil for a secondary battery negative electrode collector (negative electrode-collecting foil 5b) includes a first Cu layer (51) made of Cu or a Cu-based alloy, a stainless steel layer (52), and a second Cu layer (53) made of Cu or a Cu-based alloy, which are disposed in this order, a total thickness is 200 μm or less, and 0.01% proof stress is 500 MPa or more.

A method of inserting a rivet into a workpiece comprises moving the rivet and workpiece relative to one another, along a longitudinal axis of the rivet, so as to drive the rivet into the workpiece. The rivet is rotated about its longitudinal axis, relative to the workpiece, for at least part of the time during which it is in contact with the workpiece. The speed of said rotation, or the speed of movement along the longitudinal axis of the rivet, is altered at least once before driving of the rivet into the workpiece is complete. One axial end of the rivet has a tip for piercing the workpiece, and the rivet has a substantially cylindrical shank extending longitudinally from the tip. The shank has one or more surface irregularities.

A method of inserting a rivet into a workpiece comprises moving the rivet and workpiece relative to one another, along a longitudinal axis of the rivet, so as to drive the rivet into the workpiece. The rivet is rotated about its longitudinal axis, relative to the workpiece, for at least part of the time during which it is in contact with the workpiece. The speed of said rotation, or the speed of movement along the longitudinal axis of the rivet, is altered at least once before driving of the rivet into the workpiece is complete. One axial end of the rivet has a tip for piercing the workpiece, and the rivet has a substantially cylindrical shank extending longitudinally from the tip. The shank has one or more surface irregularities.

Aluminum alloy workpieces and/or magnesium alloy workpieces are joined in a solid state weld by use of a reactive material placed, in a suitable form, at the joining surfaces. Joining surfaces of the workpieces are pressed against the interposed reactive material and heated. The reactive material alloys or reacts with the workpiece surfaces consuming some of the surface material in forming a reaction product comprising a low melting liquid that removes oxide films and other surface impediments to a welded bond across the interface. Further pressure is applied to expel the reaction product and to join the workpiece surfaces in a solid state weld bond.

The present disclosure provides a welding electrode and methods of manufacturing the same. The welding electrode can include a composite body having a tip portion and an end portion. The composite body can include a shell defining a cavity through the end portion, the shell comprising a first metal that includes one or more of the following: a precipitation hardened copper alloy, copper alloy, and carbon steel. The composite body can also include a core within the shell, the core extending through the shell from the tip portion to the cavity, the core comprising a second metal that includes dispersion strengthened copper. The core and the shell have a metallurgical bond formed from co-extrusion.