A weld joint is disclosed that weld bonds together an aluminum workpiece and a steel workpiece. The weld joint includes an aluminum weld nugget, an intermetallic layer, and an annular ring of aluminide particles that is selected from the group consisting of nickel aluminide particles, iron aluminide particles, and a combination thereof. The annular ring of aluminide particles extends upwards from a weld bond surface of the weld joint such that the annular ring of aluminide particles extends radially inwardly into the aluminum weld nugget and protects the weld bond surface of the weld joint against crack propagation that may originate from a notch root of the weld joint.

A welding electrode is disclosed that includes an electrode welding shell and a blind adapter that are joined together to cooperatively define an internal cavity. The electrode welding shell and the blind adapter may be integrally formed or they may be distinct components that are attached together. The presence of the internal cavity defined by the electrode welding shell and the blind adapter reduces the thermal mass of the welding electrode and slows the rate of conductive heat transfer from the weld face to a cooling fluid, which allows in the center of the weld face to retain heat for a longer duration once current flow through the welding electrode is terminated, thereby positively affecting the spot welding process for particular types of workpiece stack-ups including those that include an aluminum workpiece and an overlapping adjacent steel workpiece.

A method of resistance spot welding an aluminum workpiece and an adjacent overlapping steel workpiece is disclosed in which a source of a reactive metal in a diffusible state is located along a faying interface of an aluminum workpiece and an adjacent overlapping steel workpiece. The source of the reactive metal in a diffusible state may take on a variety of forms including (1) a composite adhesive layer that includes reactive particles dispersed throughout a structural thermosetting adhesive matrix or (1) a reactive alloy layer that confronts and is in proximate contact with a faying surface of the aluminum workpiece. Once the source of a reactive material in a diffusible state is in place and the workpiece stack-up is assembled, an electrical current is passed through the workpiece stack-up and between a set of opposed welding electrodes at a weld zone to ultimately produce a weld joint.

Disclosed is a method for producing a composite material, wherein two or more composite components are arranged with respect to one another by casting to form a composite, so as to create a contact region essentially without a material bond between the composite components, wherein the composite components are thereafter materially bonded to one another in the contact region by means of a hot-rolling process.

A radially slotted welding electrode is disclosed that may be used in conjunction with a companion second welding electrode to conduct resistance spot welding on a workpiece stack-up assembly that includes a steel workpiece and an overlapping adjacent aluminum workpiece, especially when an intermediate organic material layer is disposed between the workpiece faying surfaces of the steel and aluminum workpieces. The radially slotted welding electrode includes a weld face that has a central upstanding plateau and a convex dome portion that surrounds the central upstanding plateau and which includes a plurality of circumferentially spaced trapezoidal weld face sections that include transverse upstanding arcuate ridges. Together, the central upstanding plateau and the trapezoidal weld face sections of the convex dome portion define an annular channel that surrounds the central plateau and a plurality of radial slots that communicate with and extend outwards from the central channel.

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 mounting unit includes a mounting part for a mating surface of a basic structure which cannot be welded to the mounting part and a welding element fixed in a through-bore of the mounting part. The welding element corresponds to the bore and has a thickness at least as large as the mounting part. An annular groove is formed in the welding element. A part of the welding element bounding the groove on the outside forms a form-locking connection element expanded outward and fixing the welding element in the bore by a form-locking connection toward the mounting side. A central region radially within the annular groove is a welding surface for the mating surface, is aligned with or protrudes beyond a mounting-side edge region of the bore with an overhang and is aligned with or projects over the form-locking connection element. A production method is also provided.

A method of adhesive weld bonding a light metal workpiece and a steel workpiece is disclosed that includes applying a plurality of discrete adhesive ribbons to a faying surface of the light metal workpiece, the faying surface of the steel workpiece, or both faying surfaces, and then assembling the workpieces together to establish one or more adhesive zones between the faying surfaces of the light metal and steel workpieces and a plurality of adhesive free zones amongst the adhesive zone(s). The method further includes forming a resistance spot weld that bonds the the light metal workpiece and the steel workpiece together at a spot weld location within one of the adhesive free zones. The formed spot weld includes a weld joint contained within the light metal workpiece that bonds to the faying interface of the steel workpiece.

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.

A method for hard surface deposition on aluminum metal parts of a turbine engine using MIG welding equipment which includes a pulsed current generator and pulsed filler metal wire feed, wherein the deposition is achieved using a filler metal wire whose composition is of the same nature as the composition of the aluminum alloy of the part to undergo hard surface deposition, with the pulsed metal wire feed and speed of deposition on the metal part of the turbine engine being adapted to carry out deposition without hot fissuring.